.eslintignore

@@ -1,2 +0,0 @@
-/browser.js
-/test/imagediff.js

.eslintrc.json

@@ -1,19 +0,0 @@
-{
-  "parserOptions": { "ecmaVersion": 2018 },
-  "extends": ["eslint:recommended", "prettier"],
-  "env": {
-    "node": true,
-    "es6": true
-  },
-  "rules": {
-    "no-var": "error"
-  },
-  "overrides": [
-    {
-      "files": ["test/*.js", "examples/*.js"],
-      "rules": {
-        "no-console": "off"
-      }
-    }
-  ]
-}

.gitignore

@@ -1,6 +1 @@
 node_modules
-.idea
-coverage
-examples/*.png
-browser\.js
-.nyc_output

.npmignore

@@ -1,5 +0,0 @@
-test
-examples
-.travis.yml
-appveyor.yml
-

.prettierignore

@@ -1,3 +0,0 @@
-/browser.js
-/test/imagediff.js
-.nyc_output

.travis.yml

@@ -1,9 +0,0 @@
-language: node_js
-after_success:
-  - if [ "$TRAVIS_NODE_VERSION" = "10" ]; then yarn coverage && yarn codecov; fi
-node_js:
-  - "10"
-  - "12"
-branches:
-  only:
-    - master

LICENSE

@@ -1,5 +1,4 @@
-pngjs2 original work Copyright (c) 2015 Luke Page & Original Contributors
+Copyright (c) 2012 Kuba Niegowski
-pngjs derived work Copyright (c) 2012 Kuba Niegowski
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README.md

@@ -1,411 +1,150 @@
-[![Build Status](https://travis-ci.com/lukeapage/pngjs.svg?branch=master)](https://travis-ci.com/lukeapage/pngjs) [![Build status](https://ci.appveyor.com/api/projects/status/qo5x8ayutr028108/branch/master?svg=true)](https://ci.appveyor.com/project/lukeapage/pngjs/branch/master) [![codecov](https://codecov.io/gh/lukeapage/pngjs/branch/master/graph/badge.svg)](https://codecov.io/gh/lukeapage/pngjs) [![npm version](https://badge.fury.io/js/pngjs.svg)](http://badge.fury.io/js/pngjs)
+About
-
+========
-# pngjs
+Simple PNG encoder/decoder for Node.js with no native dependencies.
-
-*This is a fork of pngjs to make it work with deno*
-
-Simple PNG encoder/decoder for ~~Node.js~~ Deno with no dependencies.
-
-Based on the original [pngjs](https://github.com/niegowski/node-pngjs) with the follow enhancements.
-
-- Support for reading 1,2,4 & 16 bit files
-- Support for reading interlace files
-- Support for reading `tTRNS` transparent colours
-- Support for writing colortype 0 (grayscale), colortype 2 (RGB), colortype 4 (grayscale alpha) and colortype 6 (RGBA)
-- Sync interface as well as async
-- API compatible with pngjs and node-pngjs
-
-Known lack of support for:
-
-- Extended PNG e.g. Animation
-- Writing in colortype 3 (indexed color)
-
-# Table of Contents
-
-- [Requirements](#requirements)
-- [Comparison Table](#comparison-table)
-- [Tests](#tests)
-- [Installation](#installation)
-- [Browser](#browser)
-- [Example](#example)
-- [Async API](#async-api)
-- [Sync API](#sync-api)
-- [Changelog](#changelog)
-
-# Comparison Table
-
-| Name          | Forked From | Sync | Async | 16 Bit | 1/2/4 Bit | Interlace | Gamma  | Encodes | Tested |
-| ------------- | ----------- | ---- | ----- | ------ | --------- | --------- | ------ | ------- | ------ |
-| pngjs         |             | Yes  | Yes   | Yes    | Yes       | Yes       | Yes    | Yes     | Yes    |
-| node-png      | pngjs       | No   | Yes   | No     | No        | No        | Hidden | Yes     | Manual |
-| png-coder     | pngjs       | No   | Yes   | Yes    | No        | No        | Hidden | Yes     | Manual |
-| pngparse      |             | No   | Yes   | No     | Yes       | No        | No     | No      | Yes    |
-| pngparse-sync | pngparse    | Yes  | No    | No     | Yes       | No        | No     | No      | Yes    |
-| png-async     |             | No   | Yes   | No     | No        | No        | No     | Yes     | Yes    |
-| png-js        |             | No   | Yes   | No     | No        | No        | No     | No      | No     |
-
-Native C++ node decoders:
-
-- png
-- png-sync (sync version of above)
-- pixel-png
-- png-img
-
-# Tests
-
-Tested using [PNG Suite](http://www.schaik.com/pngsuite/). We read every file into pngjs, output it in standard 8bit colour, synchronously and asynchronously, then compare the original with the newly saved images.
-
-To run the tests, fetch the repo (tests are not distributed via npm) and install with `npm i`, run `npm test`.
-
-The only thing not converted is gamma correction - this is because multiple vendors will do gamma correction differently, so the tests will have different results on different browsers.
-
-# Installation
 
+Installation
+===============
 ```
-$ npm install pngjs  --save
+$ npm install node-png 
 ```
 
-# Browser
+Example
-
+==========
-The package has been build with a [Browserify](browserify.org) version (`npm run browserify`) and you can use the browser version by including in your code:
-
-```
-import { PNG } from 'pngjs/browser';
-```
-
-# Example
-
 ```js
-var fs = require("fs"),
+var fs = require('fs'),
-  PNG = require("pngjs").PNG;
+    PNG = require('pngjs').PNG;
 
-fs.createReadStream("in.png")
+fs.createReadStream('in.png')
-  .pipe(
+    .pipe(new PNG({
-    new PNG({
+        filterType: 4
-      filterType: 4,
+    }))
-    })
+    .on('parsed', function() {
-  )
-  .on("parsed", function () {
-    for (var y = 0; y < this.height; y++) {
-      for (var x = 0; x < this.width; x++) {
-        var idx = (this.width * y + x) << 2;
 
-        // invert color
+        for (var y = 0; y < this.height; y++) {
-        this.data[idx] = 255 - this.data[idx];
+            for (var x = 0; x < this.width; x++) {
-        this.data[idx + 1] = 255 - this.data[idx + 1];
+                var idx = (this.width * y + x) << 2;
-        this.data[idx + 2] = 255 - this.data[idx + 2];
 
-        // and reduce opacity
+                // invert color
-        this.data[idx + 3] = this.data[idx + 3] >> 1;
+                this.data[idx] = 255 - this.data[idx];
-      }
+                this.data[idx+1] = 255 - this.data[idx+1];
-    }
+                this.data[idx+2] = 255 - this.data[idx+2];
 
-    this.pack().pipe(fs.createWriteStream("out.png"));
+                // and reduce opacity
-  });
+                this.data[idx+3] = this.data[idx+3] >> 1;
+            }
+        }
+
+        this.pack().pipe(fs.createWriteStream('out.png'));
+    });
 ```
-
 For more examples see `examples` folder.
 
-# Async API
+Documentation
+================
 
 As input any color type is accepted (grayscale, rgb, palette, grayscale with alpha, rgb with alpha) but 8 bit per sample (channel) is the only supported bit depth. Interlaced mode is not supported.
 
-## Class: PNG
+### Supported ancillary chunks
+- `gAMA` - gamma,
+- `tRNS` - transparency (but only for paletted image)
 
+
+## Class: PNG
 `PNG` is readable and writable `Stream`.
 
-### Options
 
+### Options
 - `width` - use this with `height` if you want to create png from scratch
 - `height` - as above
 - `checkCRC` - whether parser should be strict about checksums in source stream (default: `true`)
-- `deflateChunkSize` - chunk size used for deflating data chunks, this should be power of 2 and must not be less than 256 and more than 32\*1024 (default: 32 kB)
+- `deflateChunkSize` - chunk size used for deflating data chunks, this should be power of 2 and must not be less than 256 and more than 32*1024 (default: 32 kB)
-- `deflateLevel` - compression level for deflate (default: 9)
+- `deflateLevel` - compression level for delate (default: 9)
-- `deflateStrategy` - compression strategy for deflate (default: 3)
+- `deflateStrategy` - compression strategy for delate (default: 3)
-- `deflateFactory` - deflate stream factory (default: `zlib.createDeflate`)
 - `filterType` - png filtering method for scanlines (default: -1 => auto, accepts array of numbers 0-4)
-- `colorType` - the output colorType - see constants. 0 = grayscale, no alpha, 2 = color, no alpha, 4 = grayscale & alpha, 6 = color & alpha. Default currently 6, but in the future may calculate best mode.
+
-- `inputColorType` - the input colorType - see constants. Default is 6 (RGBA)
-- `bitDepth` - the bitDepth of the output, 8 or 16 bits. Input data is expected to have this bit depth.
-  16 bit data is expected in the system endianness (Default: 8)
-- `inputHasAlpha` - whether the input bitmap has 4 bytes per pixel (rgb and alpha) or 3 (rgb - no alpha).
-- `bgColor` - an object containing red, green, and blue values between 0 and 255
-  that is used when packing a PNG if alpha is not to be included (default: 255,255,255)
 
 ### Event "metadata"
-
 `function(metadata) { }`
 Image's header has been parsed, metadata contains this information:
-
 - `width` image size in pixels
 - `height` image size in pixels
 - `palette` image is paletted
 - `color` image is not grayscale
 - `alpha` image contains alpha channel
-- `interlace` image is interlaced
+
 
 ### Event: "parsed"
-
 `function(data) { }`
-Input image has been completely parsed, `data` is complete and ready for modification.
+Input image has been completly parsed, `data` is complete and ready for modification.
+
 
 ### Event: "error"
-
 `function(error) { }`
 
-### png.parse(data, [callback])
 
-Parses PNG file data. Can be `String` or `Buffer`. Alternatively you can stream data to instance of PNG.
+### png.parse(data, [callback])
+Parses PNG file data. Alternatively you can stream data to instance of PNG.
 
 Optional `callback` is once called on `error` or `parsed`. The callback gets
 two arguments `(err, data)`.
 
 Returns `this` for method chaining.
 
-#### Example
-
-```js
-new PNG({ filterType: 4 }).parse(imageData, function (error, data) {
-  console.log(error, data);
-});
-```
 
 ### png.pack()
-
 Starts converting data to PNG file Stream.
 
 Returns `this` for method chaining.
 
-### png.bitblt(dst, sx, sy, w, h, dx, dy)
 
-Helper for image manipulation, copies a rectangle of pixels from current (i.e. the source) image (`sx`, `sy`, `w`, `h`) to `dst` image (at `dx`, `dy`).
+### png.bitblt(dst, sx, sy, w, h, dx, dy)
+Helper for image manipulation, copies rectangle of pixels from current image (`sx`, `sy`, `w`, `h`) to `dst` image (at `dx`, `dy`).
 
 Returns `this` for method chaining.
 
-For example, the following code copies the top-left 100x50 px of `in.png` into dst and writes it to `out.png`:
-
-```js
-var dst = new PNG({ width: 100, height: 50 });
-fs.createReadStream("in.png")
-  .pipe(new PNG())
-  .on("parsed", function () {
-    this.bitblt(dst, 0, 0, 100, 50, 0, 0);
-    dst.pack().pipe(fs.createWriteStream("out.png"));
-  });
-```
-
-### Property: adjustGamma()
-
-Helper that takes data and adjusts it to be gamma corrected. Note that it is not 100% reliable with transparent colours because that requires knowing the background colour the bitmap is rendered on to.
-
-In tests against PNG suite it compared 100% with chrome on all 8 bit and below images. On IE there were some differences.
-
-The following example reads a file, adjusts the gamma (which sets the gamma to 0) and writes it out again, effectively removing any gamma correction from the image.
-
-```js
-fs.createReadStream("in.png")
-  .pipe(new PNG())
-  .on("parsed", function () {
-    this.adjustGamma();
-    this.pack().pipe(fs.createWriteStream("out.png"));
-  });
-```
 
 ### Property: width
-
 Width of image in pixels
 
-### Property: height
 
+### Property: height
 Height of image in pixels
 
-### Property: data
 
+### Property: data
 Buffer of image pixel data. Every pixel consists 4 bytes: R, G, B, A (opacity).
 
-### Property: gamma
 
+### Property: gamma
 Gamma of image (0 if not specified)
 
-## Packing a PNG and removing alpha (RGBA to RGB)
+Changelog
+============
 
-When removing the alpha channel from an image, there needs to be a background color to correctly
+### 0.4.0 - Jun 05 2013
-convert each pixel's transparency to the appropriate RGB value. By default, pngjs will flatten
+  - fixed reading of destroyed input stream
-the image against a white background. You can override this in the options:
 
-```js
+### 0.4.0-alpha - 29 Nov 2012
-var fs = require("fs"),
+  - added zlib deflateStrategy option, default to Z_RLE (by pdpotter)
-  PNG = require("pngjs").PNG;
+  - added possibility to use multiple filters (by pdpotter, modified by niegowski)
 
-fs.createReadStream("in.png")
+### 0.3.0-alpha - 23 Aug 2012
-  .pipe(
+  - Processing data as Streams, not complete Buffers of data
-    new PNG({
-      colorType: 2,
-      bgColor: {
-        red: 0,
-        green: 255,
-        blue: 0,
-      },
-    })
-  )
-  .on("parsed", function () {
-    this.pack().pipe(fs.createWriteStream("out.png"));
-  });
-```
 
-# Sync API
+### 0.2.0-alpha - 21 Aug 2012
+  - Input added palette, grayscale, no alpha support
+  - Better scanline filter selection
 
-## PNG.sync
+### 0.1.0-alpha - 19 Aug 2012
+  - First version
 
-### PNG.sync.read(buffer)
+License
-
+=========
-Take a buffer and returns a PNG image. The properties on the image include the meta data and `data` as per the async API above.
-
-```
-var data = fs.readFileSync('in.png');
-var png = PNG.sync.read(data);
-```
-
-### PNG.sync.write(png)
-
-Take a PNG image and returns a buffer. The properties on the image include the meta data and `data` as per the async API above.
-
-```
-var data = fs.readFileSync('in.png');
-var png = PNG.sync.read(data);
-var options = { colorType: 6 };
-var buffer = PNG.sync.write(png, options);
-fs.writeFileSync('out.png', buffer);
-```
-
-### PNG.adjustGamma(src)
-
-Adjusts the gamma of a sync image. See the async adjustGamma.
-
-```
-var data = fs.readFileSync('in.png');
-var png = PNG.sync.read(data);
-PNG.adjustGamma(png);
-```
-
-# Changelog
-
-### 5.0.0 - 15/04/2020
-
-- Drop support for Node 8
-- Browserified bundle may now contain ES20(15-20) code if the supported node version supports it. Please run the browserified version through babel if you need to support older browsers.
-
-### 4.0.1 - 15/04/2020
-
-- Fix to possible null reference in nextTick of async method
-
-### 4.0.0 - 09/04/2020
-
-- Fix issue in newer nodes with using Buffer
-- Fix async issue with some png files
-- Drop support for Node 4 & 6
-
-### 3.4.0 - 09/03/2019
-
-- Include whether the png has alpha in the meta data
-- emit an error if the image is truncated instead of hanging
-- Add a browserified version
-- speed up some mapping functions
-
-### 3.3.3 - 19/04/2018
-
-- Real fix for node 9
-
-### 3.3.2 - 16/02/2018
-
-- Fix for node 9
-
-### 3.3.1 - 15/11/2017
-
-- Bugfixes and removal of es6
-
-### 3.3.0
-
-- Add writing 16 bit channels and support for grayscale input
-
-### 3.2.0 - 30/04/2017
-
-- Support for encoding 8-bit grayscale images
-
-### 3.1.0 - 30/04/2017
-
-- Support for pngs with zlib chunks that are malformed after valid data
-
-### 3.0.1 - 16/02/2017
-
-- Fix single pixel pngs
-
-### 3.0.0 - 03/08/2016
-
-- Drop support for node below v4 and iojs. Pin to 2.3.0 to use with old, unsupported or patched node versions.
-
-### 2.3.0 - 22/04/2016
-
-- Support for sync in node 0.10
-
-### 2.2.0 - 04/12/2015
-
-- Add sync write api
-- Fix newfile example
-- Correct comparison table
-
-### 2.1.0 - 28/10/2015
-
-- rename package to pngjs
-- added 'bgColor' option
-
-### 2.0.0 - 08/10/2015
-
-- fixes to readme
-- _breaking change_ - bitblt on the png prototype now doesn't take a unused, unnecessary src first argument
-
-### 1.2.0 - 13/09/2015
-
-- support passing colorType to write PNG's and writing bitmaps without alpha information
-
-### 1.1.0 - 07/09/2015
-
-- support passing a deflate factory for controlled compression
-
-### 1.0.2 - 22/08/2015
-
-- Expose all PNG creation info
-
-### 1.0.1 - 21/08/2015
-
-- Fix non square interlaced files
-
-### 1.0.0 - 08/08/2015
-
-- More tests
-- source linted
-- maintainability refactorings
-- async API - exceptions in reading now emit warnings
-- documentation improvement - sync api now documented, adjustGamma documented
-- breaking change - gamma chunk is now written. previously a read then write would destroy gamma information, now it is persisted.
-
-### 0.0.3 - 03/08/2015
-
-- Error handling fixes
-- ignore files for smaller npm footprint
-
-### 0.0.2 - 02/08/2015
-
-- Bugfixes to interlacing, support for transparent colours
-
-### 0.0.1 - 02/08/2015
-
-- Initial release, see pngjs for older changelog.
-
-# License
 
 (The MIT License)
 
+Copyright (c) 2012 Kuba Niegowski
+
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
 in the Software without restriction, including without limitation the rights

appveyor.yml

@@ -1,28 +0,0 @@
-version: "{build}"
-
-clone_depth: 10
-
-environment:
-  matrix:
-    - nodejs_version: "10"
-    - nodejs_version: "12"
-
-install:
-  - ps: Install-Product node $env:nodejs_version
-  - npm install
-
-build: off
-
-test_script:
-  - node --version && npm --version
-  - npm test
-
-cache:
-  - node_modules # local npm modules
-
-matrix:
-  fast_finish: true
-
-branches:
-  only:
-    - master

examples/16bit_write.js

@@ -1,50 +0,0 @@
-#!/usr/bin/env node
-
-let fs = require("fs");
-let PNG = require("../lib/png").PNG;
-let w = 32;
-let h = 64;
-
-/// RGBA input (color type 6)
-let buffer = Buffer.alloc(2 * w * h * 4);
-let bitmap = new Uint16Array(buffer.buffer);
-for (let i = 0; i < h; i++) {
-  for (let j = 0; j < w; j++) {
-    bitmap[i * 4 * w + 4 * j] = (i * 65535) / h;
-    bitmap[i * 4 * w + 4 * j + 1] = (j * 65535) / w;
-    bitmap[i * 4 * w + 4 * j + 2] = ((h - i) * 65535) / h;
-    bitmap[i * 4 * w + 4 * j + 3] = 65535;
-  }
-}
-
-let png = new PNG({
-  width: w,
-  height: h,
-  bitDepth: 16,
-  colorType: 6,
-  inputColorType: 6,
-  inputHasAlpha: true,
-});
-
-png.data = buffer;
-png.pack().pipe(fs.createWriteStream("colortype6.png"));
-
-//////// Grayscale 16 bits///////
-
-buffer = Buffer.alloc(2 * w * h);
-bitmap = new Uint16Array(buffer.buffer);
-for (let i = 0; i < h; i++) {
-  for (let j = 0; j < w; j++) bitmap[i * w + j] = (i * 65535) / h;
-}
-
-png = new PNG({
-  width: w,
-  height: h,
-  bitDepth: 16,
-  colorType: 0,
-  inputColorType: 0,
-  inputHasAlpha: false,
-});
-
-png.data = buffer;
-png.pack().pipe(fs.createWriteStream("colortype0.png"));

examples/fromdocs.js

@@ -1,22 +1,26 @@
-let fs = require("fs"),
-  PNG = require("../lib/png").PNG; // note require('pngjs') outside this project
 
-fs.createReadStream("test/in/basi0g01.png")
+var fs = require('fs'),
-  .pipe(new PNG({}))
+    PNG = require('pngjs').PNG;
-  .on("parsed", function () {
-    for (let y = 0; y < this.height; y++) {
-      for (let x = 0; x < this.width; x++) {
-        let idx = (this.width * y + x) << 2;
 
-        // invert color
+fs.createReadStream('in.png')
-        this.data[idx] = 255 - this.data[idx];
+    .pipe(new PNG({
-        this.data[idx + 1] = 255 - this.data[idx + 1];
+        filterType: 4
-        this.data[idx + 2] = 255 - this.data[idx + 2];
+    }))
+    .on('parsed', function() {
 
-        // and reduce opacity
+        for (var y = 0; y < this.height; y++) {
-        this.data[idx + 3] = this.data[idx + 3] >> 1;
+            for (var x = 0; x < this.width; x++) {
-      }
+                var idx = (this.width * y + x) << 2;
-    }
 
-    this.pack().pipe(fs.createWriteStream("out.png"));
+                // invert color
-  });
+                this.data[idx] = 255 - this.data[idx];
+                this.data[idx+1] = 255 - this.data[idx+1];
+                this.data[idx+2] = 255 - this.data[idx+2];
+
+                // and reduce opacity
+                this.data[idx+3] = this.data[idx+3] >> 1;
+            }
+        }
+
+        this.pack().pipe(fs.createWriteStream('out.png'));
+    });

examples/newfile.js

@@ -1,25 +0,0 @@
-let PNG = require("../lib/png").PNG;
-let fs = require("fs");
-
-let newfile = new PNG({ width: 10, height: 10 });
-
-for (let y = 0; y < newfile.height; y++) {
-  for (let x = 0; x < newfile.width; x++) {
-    let idx = (newfile.width * y + x) << 2;
-
-    let col =
-      (x < newfile.width >> 1) ^ (y < newfile.height >> 1) ? 0xe5 : 0xff;
-
-    newfile.data[idx] = col;
-    newfile.data[idx + 1] = col;
-    newfile.data[idx + 2] = col;
-    newfile.data[idx + 3] = 0xff;
-  }
-}
-
-newfile
-  .pack()
-  .pipe(fs.createWriteStream(__dirname + "/newfile.png"))
-  .on("finish", function () {
-    console.log("Written!");
-  });

examples/set-colortype.js

@@ -1,34 +0,0 @@
-let fs = require("fs");
-let PNG = require("../lib/png").PNG;
-let w = 320;
-let h = 200;
-
-let bitmapWithoutAlpha = Buffer.alloc(w * h * 3);
-let ofs = 0;
-for (let i = 0; i < bitmapWithoutAlpha.length; i += 3) {
-  bitmapWithoutAlpha[ofs++] = 0xff;
-  bitmapWithoutAlpha[ofs++] = i % 0xff;
-  bitmapWithoutAlpha[ofs++] = (i / 3) % 0xff;
-}
-
-let png = new PNG({
-  width: w,
-  height: h,
-  bitDepth: 8,
-  colorType: 2,
-  inputHasAlpha: false,
-});
-
-png.data = bitmapWithoutAlpha;
-png.pack().pipe(fs.createWriteStream("colortype2.png"));
-
-png = new PNG({
-  width: w,
-  height: h,
-  bitDepth: 8,
-  colorType: 6,
-  inputHasAlpha: false,
-});
-
-png.data = bitmapWithoutAlpha;
-png.pack().pipe(fs.createWriteStream("colortype6.png"));

examples/simple.js

@@ -1,28 +1,30 @@
 #!/usr/bin/env node
 
-let fs = require("fs"),
+var fs = require('fs'),
-  PNG = require("../lib/png").PNG;
+    PNG = require('../lib/png').PNG;
 
-let png = new PNG({
-    filterType: -1,
-  }),
-  src = fs.createReadStream(process.argv[2]),
-  dst = fs.createWriteStream(process.argv[3] || "out.png");
 
-png.on("parsed", function () {
+var png = new PNG({
-  for (let y = 0; y < png.height; y++) {
+        filterType: -1
-    for (let x = 0; x < png.width; x++) {
+    }),
-      let idx = (png.width * y + x) << 2;
+    src = fs.createReadStream(process.argv[2]),
+    dst = fs.createWriteStream(process.argv[3] || 'out.png');
 
-      if (
+
-        Math.abs(png.data[idx] - png.data[idx + 1]) <= 1 &&
+png.on('parsed', function() {
-        Math.abs(png.data[idx + 1] - png.data[idx + 2]) <= 1
+
-      )
+    for (var y = 0; y < png.height; y++) {
-        png.data[idx] = png.data[idx + 1] = png.data[idx + 2];
+        for (var x = 0; x < png.width; x++) {
+            var idx = (png.width * y + x) << 2;
+
+            if (Math.abs(png.data[idx] - png.data[idx+1]) <= 1
+                    && Math.abs(png.data[idx+1] - png.data[idx+2]) <= 1)
+                png.data[idx] = png.data[idx+1] = png.data[idx+2];
+
+        }
     }
-  }
 
-  png.pack().pipe(dst);
+    png.pack().pipe(dst);
 });
 
 src.pipe(png);

examples/sync.js

@@ -1,18 +0,0 @@
-#!/usr/bin/env node
-
-let fs = require("fs"),
-  PNG = require("../lib/png").PNG;
-
-let srcFname = process.argv[2],
-  dstFname = process.argv[3] || "out.png";
-
-// Read a PNG file
-let data = fs.readFileSync(srcFname);
-// Parse it
-let png = PNG.sync.read(data, {
-  filterType: -1,
-});
-// Pack it back into a PNG data
-let buff = PNG.sync.write(png);
-// Write a PNG file
-fs.writeFileSync(dstFname, buff);

examples/test/bg.js

@@ -0,0 +1,27 @@
+#!/usr/bin/env node
+
+var fs = require('fs'),
+    PNG = require('pngjs').PNG;
+
+
+var png = new PNG({
+    width: 10,
+    height: 10,
+    filterType: -1
+});
+
+
+for (var y = 0; y < png.height; y++) {
+    for (var x = 0; x < png.width; x++) {
+        var idx = (png.width * y + x) << 2;
+
+        var col = x < (png.width >> 1) ^ y < (png.height >> 1) ? 0xe5 : 0xff;
+
+        png.data[idx  ] = col;
+        png.data[idx+1] = col;
+        png.data[idx+2] = col;
+        png.data[idx+3] = 0xff;
+    }
+}
+
+png.pack().pipe(fs.createWriteStream(__dirname + '/bg.png'));

examples/test/list.html

@@ -0,0 +1,38 @@
+<!DOCTYPE html>
+<html>
+<head>
+    <title>PNG Test</title>
+    <style>
+        body { background: #eee; font: 12px Arial; margin: 10px; }
+        img { margin: 2px; background: url(bg.png); }
+        h3 { margin: 10px 0; }
+    </style>
+</head>
+<body>
+    <h3>Basic</h3>
+    <img src="img/basn0g08.png"> <img src="out/basn0g08.png"> grayscale<br>
+    <img src="img/basn2c08.png"> <img src="out/basn2c08.png"> color<br>
+    <img src="img/basn3p08.png"> <img src="out/basn3p08.png"> paletted<br>
+    <img src="img/basn4a08.png"> <img src="out/basn4a08.png"> grayscale + alpha<br>
+    <img src="img/basn6a08.png"> <img src="out/basn6a08.png"> color + alpha<br>
+
+    <h3>Image filtering</h3>
+    <img src="img/f00n0g08.png"> <img src="out/f00n0g08.png"> grayscale, filter 0<br>
+    <img src="img/f00n2c08.png"> <img src="out/f00n2c08.png"> color, filter 0<br>
+    <img src="img/f01n0g08.png"> <img src="out/f01n0g08.png"> grayscale, filter 1<br>
+    <img src="img/f01n2c08.png"> <img src="out/f01n2c08.png"> color, filter 1<br>
+    <img src="img/f02n0g08.png"> <img src="out/f02n0g08.png"> grayscale, filter 2<br>
+    <img src="img/f02n2c08.png"> <img src="out/f02n2c08.png"> color, filter 2<br>
+    <img src="img/f03n0g08.png"> <img src="out/f03n0g08.png"> grayscale, filter 3<br>
+    <img src="img/f03n2c08.png"> <img src="out/f03n2c08.png"> color, filter 3<br>
+    <img src="img/f04n0g08.png"> <img src="out/f04n0g08.png"> grayscale, filter 4<br>
+    <img src="img/f04n2c08.png"> <img src="out/f04n2c08.png"> color, filter 4<br>
+
+    <h3>Transparency</h3>
+    <img src="img/tp0n0g08.png"> <img src="out/tp0n0g08.png"> grayscale, not transparent<br>
+    <img src="img/tp0n2c08.png"> <img src="out/tp0n2c08.png"> color, not transparent<br>
+    <img src="img/tp0n3p08.png"> <img src="out/tp0n3p08.png"> paletted, not transparent<br>
+    <img src="img/tbrn2c08.png"> <img src="out/tbrn2c08.png"> color, transparent<br>
+    <img src="img/tp1n3p08.png"> <img src="out/tp1n3p08.png"> paletted, transparent<br>
+</body>
+</html>

examples/test/test.js

@@ -0,0 +1,38 @@
+
+var fs = require('fs'),
+    PNG = require('pngjs').PNG;
+
+
+fs.readdir(__dirname + '/img/', function(err, files) {
+    if (err) throw err;
+
+    files.forEach(function(file) {
+
+        if (!file.match(/\.png$/i))
+            return;
+
+        fs.createReadStream(__dirname + '/img/' + file)
+            .pipe(new PNG())
+            .on('parsed', function() {
+
+                if (this.gamma) {
+                    for (var y = 0; y < this.height; y++) {
+                        for (var x = 0; x < this.width; x++) {
+                            var idx = (this.width * y + x) << 2;
+
+                            for (var i = 0; i < 3; i++) {
+                                var sample = this.data[idx + i] / 255;
+                                sample = Math.pow(sample, 1 / 2.2 / this.gamma);
+                                this.data[idx + i] = Math.round(sample * 255);
+                            }
+                        }
+                    }
+                }
+
+                this.pack()
+                    .pipe(fs.createWriteStream(__dirname + '/out/' + file));
+
+            });
+
+    });
+});

lib/bitmapper.js

@@ -1,265 +0,0 @@
-import interlaceUtils from "./interlace.js";
-
-let pixelBppMapper = [
-  // 0 - dummy entry
-  function () {},
-
-  // 1 - L
-  // 0: 0, 1: 0, 2: 0, 3: 0xff
-  function (pxData, data, pxPos, rawPos) {
-    if (rawPos === data.length) {
-      throw new Error("Ran out of data");
-    }
-
-    let pixel = data[rawPos];
-    pxData[pxPos] = pixel;
-    pxData[pxPos + 1] = pixel;
-    pxData[pxPos + 2] = pixel;
-    pxData[pxPos + 3] = 0xff;
-  },
-
-  // 2 - LA
-  // 0: 0, 1: 0, 2: 0, 3: 1
-  function (pxData, data, pxPos, rawPos) {
-    if (rawPos + 1 >= data.length) {
-      throw new Error("Ran out of data");
-    }
-
-    let pixel = data[rawPos];
-    pxData[pxPos] = pixel;
-    pxData[pxPos + 1] = pixel;
-    pxData[pxPos + 2] = pixel;
-    pxData[pxPos + 3] = data[rawPos + 1];
-  },
-
-  // 3 - RGB
-  // 0: 0, 1: 1, 2: 2, 3: 0xff
-  function (pxData, data, pxPos, rawPos) {
-    if (rawPos + 2 >= data.length) {
-      throw new Error("Ran out of data");
-    }
-
-    pxData[pxPos] = data[rawPos];
-    pxData[pxPos + 1] = data[rawPos + 1];
-    pxData[pxPos + 2] = data[rawPos + 2];
-    pxData[pxPos + 3] = 0xff;
-  },
-
-  // 4 - RGBA
-  // 0: 0, 1: 1, 2: 2, 3: 3
-  function (pxData, data, pxPos, rawPos) {
-    if (rawPos + 3 >= data.length) {
-      throw new Error("Ran out of data");
-    }
-
-    pxData[pxPos] = data[rawPos];
-    pxData[pxPos + 1] = data[rawPos + 1];
-    pxData[pxPos + 2] = data[rawPos + 2];
-    pxData[pxPos + 3] = data[rawPos + 3];
-  },
-];
-
-let pixelBppCustomMapper = [
-  // 0 - dummy entry
-  function () {},
-
-  // 1 - L
-  // 0: 0, 1: 0, 2: 0, 3: 0xff
-  function (pxData, pixelData, pxPos, maxBit) {
-    let pixel = pixelData[0];
-    pxData[pxPos] = pixel;
-    pxData[pxPos + 1] = pixel;
-    pxData[pxPos + 2] = pixel;
-    pxData[pxPos + 3] = maxBit;
-  },
-
-  // 2 - LA
-  // 0: 0, 1: 0, 2: 0, 3: 1
-  function (pxData, pixelData, pxPos) {
-    let pixel = pixelData[0];
-    pxData[pxPos] = pixel;
-    pxData[pxPos + 1] = pixel;
-    pxData[pxPos + 2] = pixel;
-    pxData[pxPos + 3] = pixelData[1];
-  },
-
-  // 3 - RGB
-  // 0: 0, 1: 1, 2: 2, 3: 0xff
-  function (pxData, pixelData, pxPos, maxBit) {
-    pxData[pxPos] = pixelData[0];
-    pxData[pxPos + 1] = pixelData[1];
-    pxData[pxPos + 2] = pixelData[2];
-    pxData[pxPos + 3] = maxBit;
-  },
-
-  // 4 - RGBA
-  // 0: 0, 1: 1, 2: 2, 3: 3
-  function (pxData, pixelData, pxPos) {
-    pxData[pxPos] = pixelData[0];
-    pxData[pxPos + 1] = pixelData[1];
-    pxData[pxPos + 2] = pixelData[2];
-    pxData[pxPos + 3] = pixelData[3];
-  },
-];
-
-function bitRetriever(data, depth) {
-  let leftOver = [];
-  let i = 0;
-
-  function split() {
-    if (i === data.length) {
-      throw new Error("Ran out of data");
-    }
-    let byte = data[i];
-    i++;
-    let byte8, byte7, byte6, byte5, byte4, byte3, byte2, byte1;
-    switch (depth) {
-      default:
-        throw new Error("unrecognised depth");
-      case 16:
-        byte2 = data[i];
-        i++;
-        leftOver.push((byte << 8) + byte2);
-        break;
-      case 4:
-        byte2 = byte & 0x0f;
-        byte1 = byte >> 4;
-        leftOver.push(byte1, byte2);
-        break;
-      case 2:
-        byte4 = byte & 3;
-        byte3 = (byte >> 2) & 3;
-        byte2 = (byte >> 4) & 3;
-        byte1 = (byte >> 6) & 3;
-        leftOver.push(byte1, byte2, byte3, byte4);
-        break;
-      case 1:
-        byte8 = byte & 1;
-        byte7 = (byte >> 1) & 1;
-        byte6 = (byte >> 2) & 1;
-        byte5 = (byte >> 3) & 1;
-        byte4 = (byte >> 4) & 1;
-        byte3 = (byte >> 5) & 1;
-        byte2 = (byte >> 6) & 1;
-        byte1 = (byte >> 7) & 1;
-        leftOver.push(byte1, byte2, byte3, byte4, byte5, byte6, byte7, byte8);
-        break;
-    }
-  }
-
-  return {
-    get: function (count) {
-      while (leftOver.length < count) {
-        split();
-      }
-      let returner = leftOver.slice(0, count);
-      leftOver = leftOver.slice(count);
-      return returner;
-    },
-    resetAfterLine: function () {
-      leftOver.length = 0;
-    },
-    end: function () {
-      if (i !== data.length) {
-        throw new Error("extra data found");
-      }
-    },
-  };
-}
-
-function mapImage8Bit(image, pxData, getPxPos, bpp, data, rawPos) {
-  // eslint-disable-line max-params
-  let imageWidth = image.width;
-  let imageHeight = image.height;
-  let imagePass = image.index;
-  for (let y = 0; y < imageHeight; y++) {
-    for (let x = 0; x < imageWidth; x++) {
-      let pxPos = getPxPos(x, y, imagePass);
-      pixelBppMapper[bpp](pxData, data, pxPos, rawPos);
-      rawPos += bpp; //eslint-disable-line no-param-reassign
-    }
-  }
-  return rawPos;
-}
-
-function mapImageCustomBit(image, pxData, getPxPos, bpp, bits, maxBit) {
-  // eslint-disable-line max-params
-  let imageWidth = image.width;
-  let imageHeight = image.height;
-  let imagePass = image.index;
-  for (let y = 0; y < imageHeight; y++) {
-    for (let x = 0; x < imageWidth; x++) {
-      let pixelData = bits.get(bpp);
-      let pxPos = getPxPos(x, y, imagePass);
-      pixelBppCustomMapper[bpp](pxData, pixelData, pxPos, maxBit);
-    }
-    bits.resetAfterLine();
-  }
-}
-
-export default function (data, bitmapInfo) {
-  let width = bitmapInfo.width;
-  let height = bitmapInfo.height;
-  let depth = bitmapInfo.depth;
-  let bpp = bitmapInfo.bpp;
-  let interlace = bitmapInfo.interlace;
-  let bits;
-
-  if (depth !== 8) {
-    bits = bitRetriever(data, depth);
-  }
-  let pxData;
-  if (depth <= 8) {
-    pxData = Buffer.alloc(width * height * 4);
-  } else {
-    pxData = new Uint16Array(width * height * 4);
-  }
-  let maxBit = Math.pow(2, depth) - 1;
-  let rawPos = 0;
-  let images;
-  let getPxPos;
-
-  if (interlace) {
-    images = interlaceUtils.getImagePasses(width, height);
-    getPxPos = interlaceUtils.getInterlaceIterator(width, height);
-  } else {
-    let nonInterlacedPxPos = 0;
-    getPxPos = function () {
-      let returner = nonInterlacedPxPos;
-      nonInterlacedPxPos += 4;
-      return returner;
-    };
-    images = [{ width: width, height: height }];
-  }
-
-  for (let imageIndex = 0; imageIndex < images.length; imageIndex++) {
-    if (depth === 8) {
-      rawPos = mapImage8Bit(
-        images[imageIndex],
-        pxData,
-        getPxPos,
-        bpp,
-        data,
-        rawPos
-      );
-    } else {
-      mapImageCustomBit(
-        images[imageIndex],
-        pxData,
-        getPxPos,
-        bpp,
-        bits,
-        maxBit
-      );
-    }
-  }
-  if (depth === 8) {
-    if (rawPos !== data.length) {
-      throw new Error("extra data found");
-    }
-  } else {
-    bits.end();
-  }
-
-  return pxData;
-};

lib/bitpacker.js

@@ -1,156 +0,0 @@
-import constants from "./constants.js";
-
-export default function (dataIn, width, height, options) {
-  let outHasAlpha =
-    [constants.COLORTYPE_COLOR_ALPHA, constants.COLORTYPE_ALPHA].indexOf(
-      options.colorType
-    ) !== -1;
-  if (options.colorType === options.inputColorType) {
-    let bigEndian = (function () {
-      let buffer = new ArrayBuffer(2);
-      new DataView(buffer).setInt16(0, 256, true /* littleEndian */);
-      // Int16Array uses the platform's endianness.
-      return new Int16Array(buffer)[0] !== 256;
-    })();
-    // If no need to convert to grayscale and alpha is present/absent in both, take a fast route
-    if (options.bitDepth === 8 || (options.bitDepth === 16 && bigEndian)) {
-      return dataIn;
-    }
-  }
-
-  // map to a UInt16 array if data is 16bit, fix endianness below
-  let data = options.bitDepth !== 16 ? dataIn : new Uint16Array(dataIn.buffer);
-
-  let maxValue = 255;
-  let inBpp = constants.COLORTYPE_TO_BPP_MAP[options.inputColorType];
-  if (inBpp === 4 && !options.inputHasAlpha) {
-    inBpp = 3;
-  }
-  let outBpp = constants.COLORTYPE_TO_BPP_MAP[options.colorType];
-  if (options.bitDepth === 16) {
-    maxValue = 65535;
-    outBpp *= 2;
-  }
-  let outData = Buffer.alloc(width * height * outBpp);
-
-  let inIndex = 0;
-  let outIndex = 0;
-
-  let bgColor = options.bgColor || {};
-  if (bgColor.red === undefined) {
-    bgColor.red = maxValue;
-  }
-  if (bgColor.green === undefined) {
-    bgColor.green = maxValue;
-  }
-  if (bgColor.blue === undefined) {
-    bgColor.blue = maxValue;
-  }
-
-  function getRGBA() {
-    let red;
-    let green;
-    let blue;
-    let alpha = maxValue;
-    switch (options.inputColorType) {
-      case constants.COLORTYPE_COLOR_ALPHA:
-        alpha = data[inIndex + 3];
-        red = data[inIndex];
-        green = data[inIndex + 1];
-        blue = data[inIndex + 2];
-        break;
-      case constants.COLORTYPE_COLOR:
-        red = data[inIndex];
-        green = data[inIndex + 1];
-        blue = data[inIndex + 2];
-        break;
-      case constants.COLORTYPE_ALPHA:
-        alpha = data[inIndex + 1];
-        red = data[inIndex];
-        green = red;
-        blue = red;
-        break;
-      case constants.COLORTYPE_GRAYSCALE:
-        red = data[inIndex];
-        green = red;
-        blue = red;
-        break;
-      default:
-        throw new Error(
-          "input color type:" +
-            options.inputColorType +
-            " is not supported at present"
-        );
-    }
-
-    if (options.inputHasAlpha) {
-      if (!outHasAlpha) {
-        alpha /= maxValue;
-        red = Math.min(
-          Math.max(Math.round((1 - alpha) * bgColor.red + alpha * red), 0),
-          maxValue
-        );
-        green = Math.min(
-          Math.max(Math.round((1 - alpha) * bgColor.green + alpha * green), 0),
-          maxValue
-        );
-        blue = Math.min(
-          Math.max(Math.round((1 - alpha) * bgColor.blue + alpha * blue), 0),
-          maxValue
-        );
-      }
-    }
-    return { red: red, green: green, blue: blue, alpha: alpha };
-  }
-
-  for (let y = 0; y < height; y++) {
-    for (let x = 0; x < width; x++) {
-      let rgba = getRGBA(data, inIndex);
-
-      switch (options.colorType) {
-        case constants.COLORTYPE_COLOR_ALPHA:
-        case constants.COLORTYPE_COLOR:
-          if (options.bitDepth === 8) {
-            outData[outIndex] = rgba.red;
-            outData[outIndex + 1] = rgba.green;
-            outData[outIndex + 2] = rgba.blue;
-            if (outHasAlpha) {
-              outData[outIndex + 3] = rgba.alpha;
-            }
-          } else {
-            outData.writeUInt16BE(rgba.red, outIndex);
-            outData.writeUInt16BE(rgba.green, outIndex + 2);
-            outData.writeUInt16BE(rgba.blue, outIndex + 4);
-            if (outHasAlpha) {
-              outData.writeUInt16BE(rgba.alpha, outIndex + 6);
-            }
-          }
-          break;
-        case constants.COLORTYPE_ALPHA:
-        case constants.COLORTYPE_GRAYSCALE: {
-          // Convert to grayscale and alpha
-          let grayscale = (rgba.red + rgba.green + rgba.blue) / 3;
-          if (options.bitDepth === 8) {
-            outData[outIndex] = grayscale;
-            if (outHasAlpha) {
-              outData[outIndex + 1] = rgba.alpha;
-            }
-          } else {
-            outData.writeUInt16BE(grayscale, outIndex);
-            if (outHasAlpha) {
-              outData.writeUInt16BE(rgba.alpha, outIndex + 2);
-            }
-          }
-          break;
-        }
-        default:
-          throw new Error("unrecognised color Type " + options.colorType);
-      }
-
-      inIndex += inBpp;
-      outIndex += outBpp;
-    }
-  }
-
-  return outData;
-};

lib/chunkstream.js

@@ -1,190 +1,200 @@
-let util = require("util");
+// Copyright (c) 2012 Kuba Niegowski
-let Stream = require("stream");
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
 
-let ChunkStream = function () {
+'use strict';
-  Stream.call(this);
 
-  this._buffers = [];
-  this._buffered = 0;
 
-  this._reads = [];
+var util = require('util'),
-  this._paused = false;
+    Stream = require('stream');
 
-  this._encoding = "utf8";
+
-  this.writable = true;
+var ChunkStream = module.exports = function() {
+    Stream.call(this);
+
+    this._buffers = [];
+    this._buffered = 0;
+
+    this._reads = [];
+    this._paused = false;
+
+    this._encoding = 'utf8';
+    this.writable = true;
 };
-
-export default ChunkStream;
-
 util.inherits(ChunkStream, Stream);
 
-ChunkStream.prototype.read = function (length, callback) {
-  this._reads.push({
-    length: Math.abs(length), // if length < 0 then at most this length
-    allowLess: length < 0,
-    func: callback,
-  });
 
-  process.nextTick(
+ChunkStream.prototype.read = function(length, callback) {
-    function () {
+
+    this._reads.push({
+        length: Math.abs(length),  // if length < 0 then at most this length
+        allowLess: length < 0,
+        func: callback
+    });
+
+    process.nextTick(function() {
       this._process();
 
       // its paused and there is not enought data then ask for more
-      if (this._paused && this._reads && this._reads.length > 0) {
+      if (this._paused && this._reads.length > 0) {
-        this._paused = false;
+          this._paused = false;
 
-        this.emit("drain");
+          this.emit('drain');
       }
-    }.bind(this)
+    }.bind(this));
-  );
 };
 
-ChunkStream.prototype.write = function (data, encoding) {
+ChunkStream.prototype.write = function(data, encoding) {
-  if (!this.writable) {
-    this.emit("error", new Error("Stream not writable"));
-    return false;
-  }
 
-  let dataBuffer;
+    if (!this.writable) {
-  if (Buffer.isBuffer(data)) {
+        this.emit('error', new Error('Stream not writable'));
-    dataBuffer = data;
+        return false;
-  } else {
+    }
-    dataBuffer = Buffer.from(data, encoding || this._encoding);
-  }
 
-  this._buffers.push(dataBuffer);
+    if (!Buffer.isBuffer(data))
-  this._buffered += dataBuffer.length;
+        data = new Buffer(data, encoding || this._encoding);
 
-  this._process();
+    this._buffers.push(data);
+    this._buffered += data.length;
 
-  // ok if there are no more read requests
-  if (this._reads && this._reads.length === 0) {
-    this._paused = true;
-  }
-
-  return this.writable && !this._paused;
-};
-
-ChunkStream.prototype.end = function (data, encoding) {
-  if (data) {
-    this.write(data, encoding);
-  }
-
-  this.writable = false;
-
-  // already destroyed
-  if (!this._buffers) {
-    return;
-  }
-
-  // enqueue or handle end
-  if (this._buffers.length === 0) {
-    this._end();
-  } else {
-    this._buffers.push(null);
     this._process();
-  }
+
+    // ok if there are no more read requests
+    if (this._reads && this._reads.length == 0)
+        this._paused = true;
+
+    return this.writable && !this._paused;
+};
+
+ChunkStream.prototype.end = function(data, encoding) {
+
+    if (data) this.write(data, encoding);
+
+    this.writable = false;
+
+    // already destroyed
+    if (!this._buffers) return;
+
+    // enqueue or handle end
+    if (this._buffers.length == 0) {
+        this._end();
+    } else {
+        this._buffers.push(null);
+        this._process();
+    }
 };
 
 ChunkStream.prototype.destroySoon = ChunkStream.prototype.end;
 
-ChunkStream.prototype._end = function () {
+ChunkStream.prototype._end = function() {
-  if (this._reads.length > 0) {
-    this.emit("error", new Error("Unexpected end of input"));
-  }
 
-  this.destroy();
+    if (this._reads.length > 0) {
-};
+        this.emit('error',
-
+            new Error('There are some read requests waitng on finished stream')
-ChunkStream.prototype.destroy = function () {
+        );
-  if (!this._buffers) {
-    return;
-  }
-
-  this.writable = false;
-  this._reads = null;
-  this._buffers = null;
-
-  this.emit("close");
-};
-
-ChunkStream.prototype._processReadAllowingLess = function (read) {
-  // ok there is any data so that we can satisfy this request
-  this._reads.shift(); // == read
-
-  // first we need to peek into first buffer
-  let smallerBuf = this._buffers[0];
-
-  // ok there is more data than we need
-  if (smallerBuf.length > read.length) {
-    this._buffered -= read.length;
-    this._buffers[0] = smallerBuf.slice(read.length);
-
-    read.func.call(this, smallerBuf.slice(0, read.length));
-  } else {
-    // ok this is less than maximum length so use it all
-    this._buffered -= smallerBuf.length;
-    this._buffers.shift(); // == smallerBuf
-
-    read.func.call(this, smallerBuf);
-  }
-};
-
-ChunkStream.prototype._processRead = function (read) {
-  this._reads.shift(); // == read
-
-  let pos = 0;
-  let count = 0;
-  let data = Buffer.alloc(read.length);
-
-  // create buffer for all data
-  while (pos < read.length) {
-    let buf = this._buffers[count++];
-    let len = Math.min(buf.length, read.length - pos);
-
-    buf.copy(data, pos, 0, len);
-    pos += len;
-
-    // last buffer wasn't used all so just slice it and leave
-    if (len !== buf.length) {
-      this._buffers[--count] = buf.slice(len);
     }
-  }
 
-  // remove all used buffers
+    this.destroy();
-  if (count > 0) {
-    this._buffers.splice(0, count);
-  }
-
-  this._buffered -= read.length;
-
-  read.func.call(this, data);
 };
 
-ChunkStream.prototype._process = function () {
+ChunkStream.prototype.destroy = function() {
-  try {
+
+    if (!this._buffers) return;
+
+    this.writable = false;
+    this._reads = null;
+    this._buffers = null;
+
+    this.emit('close');
+};
+
+ChunkStream.prototype._process = function() {
+
     // as long as there is any data and read requests
     while (this._buffered > 0 && this._reads && this._reads.length > 0) {
-      let read = this._reads[0];
 
-      // read any data (but no more than length)
+        var read = this._reads[0];
-      if (read.allowLess) {
-        this._processReadAllowingLess(read);
-      } else if (this._buffered >= read.length) {
-        // ok we can meet some expectations
 
-        this._processRead(read);
+        // read any data (but no more than length)
-      } else {
+        if (read.allowLess) {
-        // not enought data to satisfy first request in queue
+
-        // so we need to wait for more
+            // ok there is any data so that we can satisfy this request
-        break;
+            this._reads.shift(); // == read
-      }
+
+            // first we need to peek into first buffer
+            var buf = this._buffers[0];
+
+            // ok there is more data than we need
+            if (buf.length > read.length) {
+
+                this._buffered -= read.length;
+                this._buffers[0] = buf.slice(read.length);
+
+                read.func.call(this, buf.slice(0, read.length));
+
+            } else {
+                // ok this is less than maximum length so use it all
+                this._buffered -= buf.length;
+                this._buffers.shift(); // == buf
+
+                read.func.call(this, buf);
+            }
+
+        } else if (this._buffered >= read.length) {
+            // ok we can meet some expectations
+
+            this._reads.shift(); // == read
+
+            var pos = 0,
+                count = 0,
+                data = new Buffer(read.length);
+
+            // create buffer for all data
+            while (pos < read.length) {
+
+                var buf = this._buffers[count++],
+                    len = Math.min(buf.length, read.length - pos);
+
+                buf.copy(data, pos, 0, len);
+                pos += len;
+
+                // last buffer wasn't used all so just slice it and leave
+                if (len != buf.length)
+                    this._buffers[--count] = buf.slice(len);
+            }
+
+            // remove all used buffers
+            if (count > 0)
+                this._buffers.splice(0, count);
+
+            this._buffered -= read.length;
+
+            read.func.call(this, data);
+
+        } else {
+            // not enought data to satisfy first request in queue
+            // so we need to wait for more
+            break;
+        }
     }
 
-    if (this._buffers && !this.writable) {
+    if (this._buffers && this._buffers.length > 0 && this._buffers[0] == null) {
-      this._end();
+        this._end();
     }
-  } catch (ex) {
-    this.emit("error", ex);
-  }
 };

lib/constants.js

@@ -1,30 +1,38 @@
-export default {
+// Copyright (c) 2012 Kuba Niegowski
-  PNG_SIGNATURE: [0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a],
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
 
-  TYPE_IHDR: 0x49484452,
+'use strict';
-  TYPE_IEND: 0x49454e44,
-  TYPE_IDAT: 0x49444154,
-  TYPE_PLTE: 0x504c5445,
-  TYPE_tRNS: 0x74524e53, // eslint-disable-line camelcase
-  TYPE_gAMA: 0x67414d41, // eslint-disable-line camelcase
 
-  // color-type bits
-  COLORTYPE_GRAYSCALE: 0,
-  COLORTYPE_PALETTE: 1,
-  COLORTYPE_COLOR: 2,
-  COLORTYPE_ALPHA: 4, // e.g. grayscale and alpha
 
-  // color-type combinations
+module.exports = {
-  COLORTYPE_PALETTE_COLOR: 3,
-  COLORTYPE_COLOR_ALPHA: 6,
 
-  COLORTYPE_TO_BPP_MAP: {
+    PNG_SIGNATURE: [0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a],
-    0: 1,
-    2: 3,
-    3: 1,
-    4: 2,
-    6: 4,
-  },
 
-  GAMMA_DIVISION: 100000,
+    TYPE_IHDR: 0x49484452,
+    TYPE_IEND: 0x49454e44,
+    TYPE_IDAT: 0x49444154,
+    TYPE_PLTE: 0x504c5445,
+    TYPE_tRNS: 0x74524e53,
+    TYPE_gAMA: 0x67414d41,
+
+    COLOR_PALETTE: 1,
+    COLOR_COLOR: 2,
+    COLOR_ALPHA: 4
 };

lib/crc.js

@@ -1,40 +1,79 @@
-let crcTable = [];
+// Copyright (c) 2012 Kuba Niegowski
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
 
-(function () {
+'use strict';
-  for (let i = 0; i < 256; i++) {
+
-    let currentCrc = i;
+var util = require('util'),
-    for (let j = 0; j < 8; j++) {
+    Stream = require('stream');
-      if (currentCrc & 1) {
+
-        currentCrc = 0xedb88320 ^ (currentCrc >>> 1);
+
-      } else {
+var CrcStream = module.exports = function() {
-        currentCrc = currentCrc >>> 1;
+    Stream.call(this);
-      }
+
+    this._crc = -1;
+
+    this.writable = true;
+};
+util.inherits(CrcStream, Stream);
+
+
+CrcStream.prototype.write = function(data) {
+
+    for (var i = 0; i < data.length; i++) {
+        this._crc = crcTable[(this._crc ^ data[i]) & 0xff] ^ (this._crc >>> 8);
     }
-    crcTable[i] = currentCrc;
+    return true;
-  }
-})();
-
-let CrcCalculator = function () {
-  this._crc = -1;
 };
 
-export default CrcCalculator;
+CrcStream.prototype.end = function(data) {
+    if (data) this.write(data);
 
-CrcCalculator.prototype.write = function (data) {
+    this.emit('crc', this.crc32());
-  for (let i = 0; i < data.length; i++) {
-    this._crc = crcTable[(this._crc ^ data[i]) & 0xff] ^ (this._crc >>> 8);
-  }
-  return true;
 };
 
-CrcCalculator.prototype.crc32 = function () {
+CrcStream.prototype.crc32 = function() {
-  return this._crc ^ -1;
+    return this._crc ^ -1;
 };
 
-CrcCalculator.crc32 = function (buf) {
+
-  let crc = -1;
+CrcStream.crc32 = function(buf) {
-  for (let i = 0; i < buf.length; i++) {
+
-    crc = crcTable[(crc ^ buf[i]) & 0xff] ^ (crc >>> 8);
+    var crc = -1;
-  }
+    for (var i = 0; i < buf.length; i++) {
-  return crc ^ -1;
+        crc = crcTable[(crc ^ buf[i]) & 0xff] ^ (crc >>> 8);
+    }
+    return crc ^ -1;
 };
+
+
+
+var crcTable = [];
+
+for (var i = 0; i < 256; i++) {
+    var c = i;
+    for (var j = 0; j < 8; j++) {
+        if (c & 1) {
+            c = 0xedb88320 ^ (c >>> 1);
+        } else {
+            c = c >>> 1;
+        }
+    }
+    crcTable[i] = c;
+}

lib/filter-pack.js

@@ -1,169 +0,0 @@
-import paethPredictor from "./paeth-predictor.js";
-
-function filterNone(pxData, pxPos, byteWidth, rawData, rawPos) {
-  for (let x = 0; x < byteWidth; x++) {
-    rawData[rawPos + x] = pxData[pxPos + x];
-  }
-}
-
-function filterSumNone(pxData, pxPos, byteWidth) {
-  let sum = 0;
-  let length = pxPos + byteWidth;
-
-  for (let i = pxPos; i < length; i++) {
-    sum += Math.abs(pxData[i]);
-  }
-  return sum;
-}
-
-function filterSub(pxData, pxPos, byteWidth, rawData, rawPos, bpp) {
-  for (let x = 0; x < byteWidth; x++) {
-    let left = x >= bpp ? pxData[pxPos + x - bpp] : 0;
-    let val = pxData[pxPos + x] - left;
-
-    rawData[rawPos + x] = val;
-  }
-}
-
-function filterSumSub(pxData, pxPos, byteWidth, bpp) {
-  let sum = 0;
-  for (let x = 0; x < byteWidth; x++) {
-    let left = x >= bpp ? pxData[pxPos + x - bpp] : 0;
-    let val = pxData[pxPos + x] - left;
-
-    sum += Math.abs(val);
-  }
-
-  return sum;
-}
-
-function filterUp(pxData, pxPos, byteWidth, rawData, rawPos) {
-  for (let x = 0; x < byteWidth; x++) {
-    let up = pxPos > 0 ? pxData[pxPos + x - byteWidth] : 0;
-    let val = pxData[pxPos + x] - up;
-
-    rawData[rawPos + x] = val;
-  }
-}
-
-function filterSumUp(pxData, pxPos, byteWidth) {
-  let sum = 0;
-  let length = pxPos + byteWidth;
-  for (let x = pxPos; x < length; x++) {
-    let up = pxPos > 0 ? pxData[x - byteWidth] : 0;
-    let val = pxData[x] - up;
-
-    sum += Math.abs(val);
-  }
-
-  return sum;
-}
-
-function filterAvg(pxData, pxPos, byteWidth, rawData, rawPos, bpp) {
-  for (let x = 0; x < byteWidth; x++) {
-    let left = x >= bpp ? pxData[pxPos + x - bpp] : 0;
-    let up = pxPos > 0 ? pxData[pxPos + x - byteWidth] : 0;
-    let val = pxData[pxPos + x] - ((left + up) >> 1);
-
-    rawData[rawPos + x] = val;
-  }
-}
-
-function filterSumAvg(pxData, pxPos, byteWidth, bpp) {
-  let sum = 0;
-  for (let x = 0; x < byteWidth; x++) {
-    let left = x >= bpp ? pxData[pxPos + x - bpp] : 0;
-    let up = pxPos > 0 ? pxData[pxPos + x - byteWidth] : 0;
-    let val = pxData[pxPos + x] - ((left + up) >> 1);
-
-    sum += Math.abs(val);
-  }
-
-  return sum;
-}
-
-function filterPaeth(pxData, pxPos, byteWidth, rawData, rawPos, bpp) {
-  for (let x = 0; x < byteWidth; x++) {
-    let left = x >= bpp ? pxData[pxPos + x - bpp] : 0;
-    let up = pxPos > 0 ? pxData[pxPos + x - byteWidth] : 0;
-    let upleft =
-      pxPos > 0 && x >= bpp ? pxData[pxPos + x - (byteWidth + bpp)] : 0;
-    let val = pxData[pxPos + x] - paethPredictor(left, up, upleft);
-
-    rawData[rawPos + x] = val;
-  }
-}
-
-function filterSumPaeth(pxData, pxPos, byteWidth, bpp) {
-  let sum = 0;
-  for (let x = 0; x < byteWidth; x++) {
-    let left = x >= bpp ? pxData[pxPos + x - bpp] : 0;
-    let up = pxPos > 0 ? pxData[pxPos + x - byteWidth] : 0;
-    let upleft =
-      pxPos > 0 && x >= bpp ? pxData[pxPos + x - (byteWidth + bpp)] : 0;
-    let val = pxData[pxPos + x] - paethPredictor(left, up, upleft);
-
-    sum += Math.abs(val);
-  }
-
-  return sum;
-}
-
-let filters = {
-  0: filterNone,
-  1: filterSub,
-  2: filterUp,
-  3: filterAvg,
-  4: filterPaeth,
-};
-
-let filterSums = {
-  0: filterSumNone,
-  1: filterSumSub,
-  2: filterSumUp,
-  3: filterSumAvg,
-  4: filterSumPaeth,
-};
-
-export default function (pxData, width, height, options, bpp) {
-  let filterTypes;
-  if (!("filterType" in options) || options.filterType === -1) {
-    filterTypes = [0, 1, 2, 3, 4];
-  } else if (typeof options.filterType === "number") {
-    filterTypes = [options.filterType];
-  } else {
-    throw new Error("unrecognised filter types");
-  }
-
-  if (options.bitDepth === 16) {
-    bpp *= 2;
-  }
-  let byteWidth = width * bpp;
-  let rawPos = 0;
-  let pxPos = 0;
-  let rawData = Buffer.alloc((byteWidth + 1) * height);
-
-  let sel = filterTypes[0];
-
-  for (let y = 0; y < height; y++) {
-    if (filterTypes.length > 1) {
-      // find best filter for this line (with lowest sum of values)
-      let min = Infinity;
-
-      for (let i = 0; i < filterTypes.length; i++) {
-        let sum = filterSums[filterTypes[i]](pxData, pxPos, byteWidth, bpp);
-        if (sum < min) {
-          sel = filterTypes[i];
-          min = sum;
-        }
-      }
-    }
-
-    rawData[rawPos] = sel;
-    rawPos++;
-    filters[sel](pxData, pxPos, byteWidth, rawData, rawPos, bpp);
-    rawPos += byteWidth;
-    pxPos += byteWidth;
-  }
-  return rawData;
-};

lib/filter-parse-async.js

@@ -1,24 +0,0 @@
-import ChunkStream from "./chunkstream.js";
-import Filter from "./filter-parse.js";
-let util = require("util");
-
-let FilterAsync = function (bitmapInfo) {
-  ChunkStream.call(this);
-
-  let buffers = [];
-  let that = this;
-  this._filter = new Filter(bitmapInfo, {
-    read: this.read.bind(this),
-    write: function (buffer) {
-      buffers.push(buffer);
-    },
-    complete: function () {
-      that.emit("complete", Buffer.concat(buffers));
-    },
-  });
-
-  this._filter.start();
-};
-util.inherits(FilterAsync, ChunkStream);
-
-export default FilterAsync;

lib/filter-parse-sync.js

@@ -1,19 +0,0 @@
-import SyncReader from "./sync-reader.js";
-import Filter from "./filter-parse.js";
-
-export default function (inBuffer, bitmapInfo) {
-  let outBuffers = [];
-  let reader = new SyncReader(inBuffer);
-  let filter = new Filter(bitmapInfo, {
-    read: reader.read.bind(reader),
-    write: function (bufferPart) {
-      outBuffers.push(bufferPart);
-    },
-    complete: function () {},
-  });
-
-  filter.start();
-  reader.process();
-
-  return Buffer.concat(outBuffers);
-};

lib/filter-parse.js

@@ -1,177 +0,0 @@
-import interlaceUtils from "./interlace.js";
-import paethPredictor from "./paeth-predictor.js";
-
-function getByteWidth(width, bpp, depth) {
-  let byteWidth = width * bpp;
-  if (depth !== 8) {
-    byteWidth = Math.ceil(byteWidth / (8 / depth));
-  }
-  return byteWidth;
-}
-
-let Filter = function (bitmapInfo, dependencies) {
-  let width = bitmapInfo.width;
-  let height = bitmapInfo.height;
-  let interlace = bitmapInfo.interlace;
-  let bpp = bitmapInfo.bpp;
-  let depth = bitmapInfo.depth;
-
-  this.read = dependencies.read;
-  this.write = dependencies.write;
-  this.complete = dependencies.complete;
-
-  this._imageIndex = 0;
-  this._images = [];
-  if (interlace) {
-    let passes = interlaceUtils.getImagePasses(width, height);
-    for (let i = 0; i < passes.length; i++) {
-      this._images.push({
-        byteWidth: getByteWidth(passes[i].width, bpp, depth),
-        height: passes[i].height,
-        lineIndex: 0,
-      });
-    }
-  } else {
-    this._images.push({
-      byteWidth: getByteWidth(width, bpp, depth),
-      height: height,
-      lineIndex: 0,
-    });
-  }
-
-  // when filtering the line we look at the pixel to the left
-  // the spec also says it is done on a byte level regardless of the number of pixels
-  // so if the depth is byte compatible (8 or 16) we subtract the bpp in order to compare back
-  // a pixel rather than just a different byte part. However if we are sub byte, we ignore.
-  if (depth === 8) {
-    this._xComparison = bpp;
-  } else if (depth === 16) {
-    this._xComparison = bpp * 2;
-  } else {
-    this._xComparison = 1;
-  }
-};
-
-export default Filter;
-
-Filter.prototype.start = function () {
-  this.read(
-    this._images[this._imageIndex].byteWidth + 1,
-    this._reverseFilterLine.bind(this)
-  );
-};
-
-Filter.prototype._unFilterType1 = function (
-  rawData,
-  unfilteredLine,
-  byteWidth
-) {
-  let xComparison = this._xComparison;
-  let xBiggerThan = xComparison - 1;
-
-  for (let x = 0; x < byteWidth; x++) {
-    let rawByte = rawData[1 + x];
-    let f1Left = x > xBiggerThan ? unfilteredLine[x - xComparison] : 0;
-    unfilteredLine[x] = rawByte + f1Left;
-  }
-};
-
-Filter.prototype._unFilterType2 = function (
-  rawData,
-  unfilteredLine,
-  byteWidth
-) {
-  let lastLine = this._lastLine;
-
-  for (let x = 0; x < byteWidth; x++) {
-    let rawByte = rawData[1 + x];
-    let f2Up = lastLine ? lastLine[x] : 0;
-    unfilteredLine[x] = rawByte + f2Up;
-  }
-};
-
-Filter.prototype._unFilterType3 = function (
-  rawData,
-  unfilteredLine,
-  byteWidth
-) {
-  let xComparison = this._xComparison;
-  let xBiggerThan = xComparison - 1;
-  let lastLine = this._lastLine;
-
-  for (let x = 0; x < byteWidth; x++) {
-    let rawByte = rawData[1 + x];
-    let f3Up = lastLine ? lastLine[x] : 0;
-    let f3Left = x > xBiggerThan ? unfilteredLine[x - xComparison] : 0;
-    let f3Add = Math.floor((f3Left + f3Up) / 2);
-    unfilteredLine[x] = rawByte + f3Add;
-  }
-};
-
-Filter.prototype._unFilterType4 = function (
-  rawData,
-  unfilteredLine,
-  byteWidth
-) {
-  let xComparison = this._xComparison;
-  let xBiggerThan = xComparison - 1;
-  let lastLine = this._lastLine;
-
-  for (let x = 0; x < byteWidth; x++) {
-    let rawByte = rawData[1 + x];
-    let f4Up = lastLine ? lastLine[x] : 0;
-    let f4Left = x > xBiggerThan ? unfilteredLine[x - xComparison] : 0;
-    let f4UpLeft = x > xBiggerThan && lastLine ? lastLine[x - xComparison] : 0;
-    let f4Add = paethPredictor(f4Left, f4Up, f4UpLeft);
-    unfilteredLine[x] = rawByte + f4Add;
-  }
-};
-
-Filter.prototype._reverseFilterLine = function (rawData) {
-  let filter = rawData[0];
-  let unfilteredLine;
-  let currentImage = this._images[this._imageIndex];
-  let byteWidth = currentImage.byteWidth;
-
-  if (filter === 0) {
-    unfilteredLine = rawData.slice(1, byteWidth + 1);
-  } else {
-    unfilteredLine = Buffer.alloc(byteWidth);
-
-    switch (filter) {
-      case 1:
-        this._unFilterType1(rawData, unfilteredLine, byteWidth);
-        break;
-      case 2:
-        this._unFilterType2(rawData, unfilteredLine, byteWidth);
-        break;
-      case 3:
-        this._unFilterType3(rawData, unfilteredLine, byteWidth);
-        break;
-      case 4:
-        this._unFilterType4(rawData, unfilteredLine, byteWidth);
-        break;
-      default:
-        throw new Error("Unrecognised filter type - " + filter);
-    }
-  }
-
-  this.write(unfilteredLine);
-
-  currentImage.lineIndex++;
-  if (currentImage.lineIndex >= currentImage.height) {
-    this._lastLine = null;
-    this._imageIndex++;
-    currentImage = this._images[this._imageIndex];
-  } else {
-    this._lastLine = unfilteredLine;
-  }
-
-  if (currentImage) {
-    // read, using the byte width that may be from the new current image
-    this.read(currentImage.byteWidth + 1, this._reverseFilterLine.bind(this));
-  } else {
-    this._lastLine = null;
-    this.complete();
-  }
-};

lib/filter.js

@@ -0,0 +1,314 @@
+// Copyright (c) 2012 Kuba Niegowski
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+'use strict';
+
+var util = require('util'),
+    zlib = require('zlib'),
+    ChunkStream = require('./chunkstream');
+
+
+var Filter = module.exports = function(width, height, Bpp, data, options) {
+    ChunkStream.call(this);
+
+    this._width = width;
+    this._height = height;
+    this._Bpp = Bpp;
+    this._data = data;
+    this._options = options;
+
+    this._line = 0;
+
+    if (!('filterType' in options) || options.filterType == -1) {
+        options.filterType = [0, 1, 2, 3, 4];
+    } else if (typeof options.filterType == 'number') {
+        options.filterType = [options.filterType];
+    }
+
+    this._filters = {
+        0: this._filterNone.bind(this),
+        1: this._filterSub.bind(this),
+        2: this._filterUp.bind(this),
+        3: this._filterAvg.bind(this),
+        4: this._filterPaeth.bind(this)
+    };
+
+    this.read(this._width * Bpp + 1, this._reverseFilterLine.bind(this));
+};
+util.inherits(Filter, ChunkStream);
+
+
+var pixelBppMap = {
+    1: { // L
+        0: 0,
+        1: 0,
+        2: 0,
+        3: 0xff
+    },
+    2: { // LA
+        0: 0,
+        1: 0,
+        2: 0,
+        3: 1
+    },
+    3: { // RGB
+        0: 0,
+        1: 1,
+        2: 2,
+        3: 0xff
+    },
+    4: { // RGBA
+        0: 0,
+        1: 1,
+        2: 2,
+        3: 3
+    }
+};
+
+Filter.prototype._reverseFilterLine = function(rawData) {
+
+    var pxData = this._data,
+        pxLineLength = this._width << 2,
+        pxRowPos = this._line * pxLineLength,
+        filter = rawData[0];
+
+    if (filter == 0) {
+        for (var x = 0; x < this._width; x++) {
+            var pxPos = pxRowPos + (x << 2),
+                rawPos = 1 + x * this._Bpp;
+
+            for (var i = 0; i < 4; i++) {
+                var idx = pixelBppMap[this._Bpp][i];
+                pxData[pxPos + i] = idx != 0xff ? rawData[rawPos + idx] : 0xff;
+            }
+        }
+
+    } else if (filter == 1) {
+        for (var x = 0; x < this._width; x++) {
+            var pxPos = pxRowPos + (x << 2),
+                rawPos = 1 + x * this._Bpp;
+
+            for (var i = 0; i < 4; i++) {
+                var idx = pixelBppMap[this._Bpp][i],
+                    left = x > 0 ? pxData[pxPos + i - 4] : 0;
+
+                pxData[pxPos + i] = idx != 0xff ? rawData[rawPos + idx] + left : 0xff;
+            }
+        }
+
+    } else if (filter == 2) {
+        for (var x = 0; x < this._width; x++) {
+            var pxPos = pxRowPos + (x << 2),
+                rawPos = 1 + x * this._Bpp;
+
+            for (var i = 0; i < 4; i++) {
+                var idx = pixelBppMap[this._Bpp][i],
+                    up = this._line > 0 ? pxData[pxPos - pxLineLength + i] : 0;
+
+                pxData[pxPos + i] = idx != 0xff ? rawData[rawPos + idx] + up : 0xff;
+            }
+
+        }
+
+    } else if (filter == 3) {
+        for (var x = 0; x < this._width; x++) {
+            var pxPos = pxRowPos + (x << 2),
+                rawPos = 1 + x * this._Bpp;
+
+            for (var i = 0; i < 4; i++) {
+                var idx = pixelBppMap[this._Bpp][i],
+                    left = x > 0 ? pxData[pxPos + i - 4] : 0,
+                    up = this._line > 0 ? pxData[pxPos - pxLineLength + i] : 0,
+                    add = Math.floor((left + up) / 2);
+
+                 pxData[pxPos + i] = idx != 0xff ? rawData[rawPos + idx] + add : 0xff;
+            }
+
+        }
+
+    } else if (filter == 4) {
+        for (var x = 0; x < this._width; x++) {
+            var pxPos = pxRowPos + (x << 2),
+                rawPos = 1 + x * this._Bpp;
+
+            for (var i = 0; i < 4; i++) {
+                var idx = pixelBppMap[this._Bpp][i],
+                    left = x > 0 ? pxData[pxPos + i - 4] : 0,
+                    up = this._line > 0 ? pxData[pxPos - pxLineLength + i] : 0,
+                    upLeft = x > 0 && this._line > 0
+                            ? pxData[pxPos - pxLineLength + i - 4] : 0,
+                    add = PaethPredictor(left, up, upLeft);
+
+                pxData[pxPos + i] = idx != 0xff ? rawData[rawPos + idx] + add : 0xff;
+            }
+        }
+    }
+
+
+    this._line++;
+
+    if (this._line < this._height)
+        this.read(this._width * this._Bpp + 1, this._reverseFilterLine.bind(this));
+    else
+        this.emit('complete', this._data, this._width, this._height);
+};
+
+
+
+
+Filter.prototype.filter = function() {
+
+    var pxData = this._data,
+        rawData = new Buffer(((this._width << 2) + 1) * this._height);
+
+    for (var y = 0; y < this._height; y++) {
+
+        // find best filter for this line (with lowest sum of values)
+        var filterTypes = this._options.filterType,
+            min = Infinity,
+            sel = 0;
+
+        for (var i = 0; i < filterTypes.length; i++) {
+            var sum = this._filters[filterTypes[i]](pxData, y, null);
+            if (sum < min) {
+                sel = filterTypes[i];
+                min = sum;
+            }
+        }
+
+        this._filters[sel](pxData, y, rawData);
+    }
+    return rawData;
+};
+
+Filter.prototype._filterNone = function(pxData, y, rawData) {
+
+    var pxRowLength = this._width << 2,
+        rawRowLength = pxRowLength + 1,
+        sum = 0;
+
+    if (!rawData) {
+        for (var x = 0; x < pxRowLength; x++)
+            sum += Math.abs(pxData[y * pxRowLength + x]);
+
+    } else {
+        rawData[y * rawRowLength] = 0;
+        pxData.copy(rawData, rawRowLength * y + 1, pxRowLength * y, pxRowLength * (y + 1));
+    }
+
+    return sum;
+};
+
+Filter.prototype._filterSub = function(pxData, y, rawData) {
+
+    var pxRowLength = this._width << 2,
+        rawRowLength = pxRowLength + 1,
+        sum = 0;
+
+    if (rawData)
+        rawData[y * rawRowLength] = 1;
+
+    for (var x = 0; x < pxRowLength; x++) {
+
+        var left = x >= 4 ? pxData[y * pxRowLength + x - 4] : 0,
+            val = pxData[y * pxRowLength + x] - left;
+
+        if (!rawData) sum += Math.abs(val);
+        else rawData[y * rawRowLength + 1 + x] = val;
+    }
+    return sum;
+};
+
+Filter.prototype._filterUp = function(pxData, y, rawData) {
+
+    var pxRowLength = this._width << 2,
+        rawRowLength = pxRowLength + 1,
+        sum = 0;
+
+    if (rawData)
+        rawData[y * rawRowLength] = 2;
+
+    for (var x = 0; x < pxRowLength; x++) {
+
+        var up = y > 0 ? pxData[(y - 1) * pxRowLength + x] : 0,
+            val = pxData[y * pxRowLength + x] - up;
+
+        if (!rawData) sum += Math.abs(val);
+        else rawData[y * rawRowLength + 1 + x] = val;
+    }
+    return sum;
+};
+
+Filter.prototype._filterAvg = function(pxData, y, rawData) {
+
+    var pxRowLength = this._width << 2,
+        rawRowLength = pxRowLength + 1,
+        sum = 0;
+
+    if (rawData)
+        rawData[y * rawRowLength] = 3;
+
+    for (var x = 0; x < pxRowLength; x++) {
+
+        var left = x >= 4 ? pxData[y * pxRowLength + x - 4] : 0,
+            up = y > 0 ? pxData[(y - 1) * pxRowLength + x] : 0,
+            val = pxData[y * pxRowLength + x] - ((left + up) >> 1);
+
+        if (!rawData) sum += Math.abs(val);
+        else rawData[y * rawRowLength + 1 + x] = val;
+    }
+    return sum;
+};
+
+Filter.prototype._filterPaeth = function(pxData, y, rawData) {
+
+    var pxRowLength = this._width << 2,
+        rawRowLength = pxRowLength + 1,
+        sum = 0;
+
+    if (rawData)
+        rawData[y * rawRowLength] = 4;
+
+    for (var x = 0; x < pxRowLength; x++) {
+
+        var left = x >= 4 ? pxData[y * pxRowLength + x - 4] : 0,
+            up = y > 0 ? pxData[(y - 1) * pxRowLength + x] : 0,
+            upLeft = x >= 4 && y > 0 ? pxData[(y - 1) * pxRowLength + x - 4] : 0,
+            val = pxData[y * pxRowLength + x] - PaethPredictor(left, up, upLeft);
+
+        if (!rawData) sum += Math.abs(val);
+        else rawData[y * rawRowLength + 1 + x] = val;
+    }
+    return sum;
+};
+
+
+
+var PaethPredictor = function(left, above, upLeft) {
+
+    var p = left + above - upLeft,
+        pLeft = Math.abs(p - left),
+        pAbove = Math.abs(p - above),
+        pUpLeft = Math.abs(p - upLeft);
+
+    if (pLeft <= pAbove && pLeft <= pUpLeft) return left;
+    else if (pAbove <= pUpLeft) return above;
+    else return upLeft;
+};

lib/format-normaliser.js

@@ -1,91 +0,0 @@
-function dePalette(indata, outdata, width, height, palette) {
-  let pxPos = 0;
-  // use values from palette
-  for (let y = 0; y < height; y++) {
-    for (let x = 0; x < width; x++) {
-      let color = palette[indata[pxPos]];
-
-      if (!color) {
-        throw new Error("index " + indata[pxPos] + " not in palette");
-      }
-
-      for (let i = 0; i < 4; i++) {
-        outdata[pxPos + i] = color[i];
-      }
-      pxPos += 4;
-    }
-  }
-}
-
-function replaceTransparentColor(indata, outdata, width, height, transColor) {
-  let pxPos = 0;
-  for (let y = 0; y < height; y++) {
-    for (let x = 0; x < width; x++) {
-      let makeTrans = false;
-
-      if (transColor.length === 1) {
-        if (transColor[0] === indata[pxPos]) {
-          makeTrans = true;
-        }
-      } else if (
-        transColor[0] === indata[pxPos] &&
-        transColor[1] === indata[pxPos + 1] &&
-        transColor[2] === indata[pxPos + 2]
-      ) {
-        makeTrans = true;
-      }
-      if (makeTrans) {
-        for (let i = 0; i < 4; i++) {
-          outdata[pxPos + i] = 0;
-        }
-      }
-      pxPos += 4;
-    }
-  }
-}
-
-function scaleDepth(indata, outdata, width, height, depth) {
-  let maxOutSample = 255;
-  let maxInSample = Math.pow(2, depth) - 1;
-  let pxPos = 0;
-
-  for (let y = 0; y < height; y++) {
-    for (let x = 0; x < width; x++) {
-      for (let i = 0; i < 4; i++) {
-        outdata[pxPos + i] = Math.floor(
-          (indata[pxPos + i] * maxOutSample) / maxInSample + 0.5
-        );
-      }
-      pxPos += 4;
-    }
-  }
-}
-
-export default function (indata, imageData) {
-  let depth = imageData.depth;
-  let width = imageData.width;
-  let height = imageData.height;
-  let colorType = imageData.colorType;
-  let transColor = imageData.transColor;
-  let palette = imageData.palette;
-
-  let outdata = indata; // only different for 16 bits
-
-  if (colorType === 3) {
-    // paletted
-    dePalette(indata, outdata, width, height, palette);
-  } else {
-    if (transColor) {
-      replaceTransparentColor(indata, outdata, width, height, transColor);
-    }
-    // if it needs scaling
-    if (depth !== 8) {
-      // if we need to change the buffer size
-      if (depth === 16) {
-        outdata = Buffer.alloc(width * height * 4);
-      }
-      scaleDepth(indata, outdata, width, height, depth);
-    }
-  }
-  return outdata;
-};

lib/interlace.js

@@ -1,98 +0,0 @@
-// Adam 7
-//   0 1 2 3 4 5 6 7
-// 0 x 6 4 6 x 6 4 6
-// 1 7 7 7 7 7 7 7 7
-// 2 5 6 5 6 5 6 5 6
-// 3 7 7 7 7 7 7 7 7
-// 4 3 6 4 6 3 6 4 6
-// 5 7 7 7 7 7 7 7 7
-// 6 5 6 5 6 5 6 5 6
-// 7 7 7 7 7 7 7 7 7
-
-let imagePasses = [
-  {
-    // pass 1 - 1px
-    x: [0],
-    y: [0],
-  },
-  {
-    // pass 2 - 1px
-    x: [4],
-    y: [0],
-  },
-  {
-    // pass 3 - 2px
-    x: [0, 4],
-    y: [4],
-  },
-  {
-    // pass 4 - 4px
-    x: [2, 6],
-    y: [0, 4],
-  },
-  {
-    // pass 5 - 8px
-    x: [0, 2, 4, 6],
-    y: [2, 6],
-  },
-  {
-    // pass 6 - 16px
-    x: [1, 3, 5, 7],
-    y: [0, 2, 4, 6],
-  },
-  {
-    // pass 7 - 32px
-    x: [0, 1, 2, 3, 4, 5, 6, 7],
-    y: [1, 3, 5, 7],
-  },
-];
-
-export var getImagePasses = function (width, height) {
-  let images = [];
-  let xLeftOver = width % 8;
-  let yLeftOver = height % 8;
-  let xRepeats = (width - xLeftOver) / 8;
-  let yRepeats = (height - yLeftOver) / 8;
-  for (let i = 0; i < imagePasses.length; i++) {
-    let pass = imagePasses[i];
-    let passWidth = xRepeats * pass.x.length;
-    let passHeight = yRepeats * pass.y.length;
-    for (let j = 0; j < pass.x.length; j++) {
-      if (pass.x[j] < xLeftOver) {
-        passWidth++;
-      } else {
-        break;
-      }
-    }
-    for (let j = 0; j < pass.y.length; j++) {
-      if (pass.y[j] < yLeftOver) {
-        passHeight++;
-      } else {
-        break;
-      }
-    }
-    if (passWidth > 0 && passHeight > 0) {
-      images.push({ width: passWidth, height: passHeight, index: i });
-    }
-  }
-  return images;
-};
-
-export var getInterlaceIterator = function (width) {
-  return function (x, y, pass) {
-    let outerXLeftOver = x % imagePasses[pass].x.length;
-    let outerX =
-      ((x - outerXLeftOver) / imagePasses[pass].x.length) * 8 +
-      imagePasses[pass].x[outerXLeftOver];
-    let outerYLeftOver = y % imagePasses[pass].y.length;
-    let outerY =
-      ((y - outerYLeftOver) / imagePasses[pass].y.length) * 8 +
-      imagePasses[pass].y[outerYLeftOver];
-    return outerX * 4 + outerY * width * 4;
-  };
-};
-
-export default {
-  getImagePasses,
-  getInterlaceIterator
-}

lib/packer-async.js

@@ -1,51 +0,0 @@
-let util = require("util");
-let Stream = require("stream");
-
-import constants from "./constants.js";
-import Packer from "./packer.js";
-
-let PackerAsync = function (opt) {
-  Stream.call(this);
-
-  let options = opt || {};
-
-  this._packer = new Packer(options);
-  this._deflate = this._packer.createDeflate();
-
-  this.readable = true;
-};
-util.inherits(PackerAsync, Stream);
-
-export default PackerAsync;
-
-PackerAsync.prototype.pack = function (data, width, height, gamma) {
-  // Signature
-  this.emit("data", Buffer.from(constants.PNG_SIGNATURE));
-  this.emit("data", this._packer.packIHDR(width, height));
-
-  if (gamma) {
-    this.emit("data", this._packer.packGAMA(gamma));
-  }
-
-  let filteredData = this._packer.filterData(data, width, height);
-
-  // compress it
-  this._deflate.on("error", this.emit.bind(this, "error"));
-
-  this._deflate.on(
-    "data",
-    function (compressedData) {
-      this.emit("data", this._packer.packIDAT(compressedData));
-    }.bind(this)
-  );
-
-  this._deflate.on(
-    "end",
-    function () {
-      this.emit("data", this._packer.packIEND());
-      this.emit("end");
-    }.bind(this)
-  );
-
-  this._deflate.end(filteredData);
-};

lib/packer-sync.js

@@ -1,52 +0,0 @@
-import constants from "./constants.js";
-import Packer from "./packer.js";
-
-let hasSyncZlib = true;
-let zlib = require("zlib");
-
-export default function (metaData, opt) {
-  if (!hasSyncZlib) {
-    throw new Error(
-      "To use the sync capability of this library in old node versions, please pin pngjs to v2.3.0"
-    );
-  }
-
-  let options = opt || {};
-
-  let packer = new Packer(options);
-
-  let chunks = [];
-
-  // Signature
-  chunks.push(Buffer.from(constants.PNG_SIGNATURE));
-
-  // Header
-  chunks.push(packer.packIHDR(metaData.width, metaData.height));
-
-  if (metaData.gamma) {
-    chunks.push(packer.packGAMA(metaData.gamma));
-  }
-
-  let filteredData = packer.filterData(
-    metaData.data,
-    metaData.width,
-    metaData.height
-  );
-
-  // compress it
-  let compressedData = zlib.deflateSync(
-    filteredData,
-    packer.getDeflateOptions()
-  );
-  filteredData = null;
-
-  if (!compressedData || !compressedData.length) {
-    throw new Error("bad png - invalid compressed data response");
-  }
-  chunks.push(packer.packIDAT(compressedData));
-
-  // End
-  chunks.push(packer.packIEND());
-
-  return Buffer.concat(chunks);
-};

lib/packer.js

@@ -1,130 +1,110 @@
-import constants from "./constants.js";
+// Copyright (c) 2012 Kuba Niegowski
-import CrcStream from "./crc.js";
+//
-import bitPacker from "./bitpacker.js";
+// Permission is hereby granted, free of charge, to any person obtaining a copy
-import filter from "./filter-pack.js";
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
 
-let zlib = require("zlib");
+'use strict';
 
-let Packer = function (options) {
-  this._options = options;
 
-  options.deflateChunkSize = options.deflateChunkSize || 32 * 1024;
+var util = require('util'),
-  options.deflateLevel =
+    Stream = require('stream'),
-    options.deflateLevel != null ? options.deflateLevel : 9;
+    zlib = require('zlib'),
-  options.deflateStrategy =
+    Filter = require('./filter'),
-    options.deflateStrategy != null ? options.deflateStrategy : 3;
+    CrcStream = require('./crc'),
-  options.inputHasAlpha =
+    constants = require('./constants');
-    options.inputHasAlpha != null ? options.inputHasAlpha : true;
-  options.deflateFactory = options.deflateFactory || zlib.createDeflate;
-  options.bitDepth = options.bitDepth || 8;
-  // This is outputColorType
-  options.colorType =
-    typeof options.colorType === "number"
-      ? options.colorType
-      : constants.COLORTYPE_COLOR_ALPHA;
-  options.inputColorType =
-    typeof options.inputColorType === "number"
-      ? options.inputColorType
-      : constants.COLORTYPE_COLOR_ALPHA;
 
-  if (
+
-    [
+var Packer = module.exports = function(options) {
-      constants.COLORTYPE_GRAYSCALE,
+    Stream.call(this);
-      constants.COLORTYPE_COLOR,
+
-      constants.COLORTYPE_COLOR_ALPHA,
+    this._options = options;
-      constants.COLORTYPE_ALPHA,
+
-    ].indexOf(options.colorType) === -1
+    options.deflateChunkSize = options.deflateChunkSize || 32 * 1024;
-  ) {
+    options.deflateLevel = options.deflateLevel || 9;
-    throw new Error(
+    options.deflateStrategy = options.deflateStrategy || 3;
-      "option color type:" + options.colorType + " is not supported at present"
+
-    );
+    this.readable = true;
-  }
+};
-  if (
+util.inherits(Packer, Stream);
-    [
+
-      constants.COLORTYPE_GRAYSCALE,
+
-      constants.COLORTYPE_COLOR,
+Packer.prototype.pack = function(data, width, height) {
-      constants.COLORTYPE_COLOR_ALPHA,
+
-      constants.COLORTYPE_ALPHA,
+    // Signature
-    ].indexOf(options.inputColorType) === -1
+    this.emit('data', new Buffer(constants.PNG_SIGNATURE));
-  ) {
+    this.emit('data', this._packIHDR(width, height));
-    throw new Error(
+
-      "option input color type:" +
+    // filter pixel data
-        options.inputColorType +
+    var filter = new Filter(width, height, 4, data, this._options);
-        " is not supported at present"
+    var data = filter.filter();
-    );
+
-  }
+    // compress it
-  if (options.bitDepth !== 8 && options.bitDepth !== 16) {
+    var deflate = zlib.createDeflate({
-    throw new Error(
+            chunkSize: this._options.deflateChunkSize,
-      "option bit depth:" + options.bitDepth + " is not supported at present"
+            level: this._options.deflateLevel,
-    );
+            strategy: this._options.deflateStrategy
-  }
+        });
+    deflate.on('error', this.emit.bind(this, 'error'));
+
+    deflate.on('data', function(data) {
+        this.emit('data', this._packIDAT(data));
+    }.bind(this));
+
+    deflate.on('end', function() {
+        this.emit('data', this._packIEND());
+        this.emit('end');
+    }.bind(this));
+
+    deflate.end(data);
 };
 
-export default Packer;
+Packer.prototype._packChunk = function(type, data) {
 
-Packer.prototype.getDeflateOptions = function () {
+    var len = (data ? data.length : 0),
-  return {
+        buf = new Buffer(len + 12);
-    chunkSize: this._options.deflateChunkSize,
+
-    level: this._options.deflateLevel,
+    buf.writeUInt32BE(len, 0);
-    strategy: this._options.deflateStrategy,
+    buf.writeUInt32BE(type, 4);
-  };
+
+    if (data) data.copy(buf, 8);
+
+    buf.writeInt32BE(CrcStream.crc32(buf.slice(4, buf.length - 4)), buf.length - 4);
+    return buf;
 };
 
-Packer.prototype.createDeflate = function () {
+Packer.prototype._packIHDR = function(width, height) {
-  return this._options.deflateFactory(this.getDeflateOptions());
+
+    var buf = new Buffer(13);
+    buf.writeUInt32BE(width, 0);
+    buf.writeUInt32BE(height, 4);
+    buf[8] = 8;
+    buf[9] = 6; // colorType
+    buf[10] = 0; // compression
+    buf[11] = 0; // filter
+    buf[12] = 0; // interlace
+
+    return this._packChunk(constants.TYPE_IHDR, buf);
 };
 
-Packer.prototype.filterData = function (data, width, height) {
+Packer.prototype._packIDAT = function(data) {
-  // convert to correct format for filtering (e.g. right bpp and bit depth)
+    return this._packChunk(constants.TYPE_IDAT, data);
-  let packedData = bitPacker(data, width, height, this._options);
-
-  // filter pixel data
-  let bpp = constants.COLORTYPE_TO_BPP_MAP[this._options.colorType];
-  let filteredData = filter(packedData, width, height, this._options, bpp);
-  return filteredData;
 };
 
-Packer.prototype._packChunk = function (type, data) {
+Packer.prototype._packIEND = function() {
-  let len = data ? data.length : 0;
+    return this._packChunk(constants.TYPE_IEND, null);
-  let buf = Buffer.alloc(len + 12);
-
-  buf.writeUInt32BE(len, 0);
-  buf.writeUInt32BE(type, 4);
-
-  if (data) {
-    data.copy(buf, 8);
-  }
-
-  buf.writeInt32BE(
-    CrcStream.crc32(buf.slice(4, buf.length - 4)),
-    buf.length - 4
-  );
-  return buf;
-};
-
-Packer.prototype.packGAMA = function (gamma) {
-  let buf = Buffer.alloc(4);
-  buf.writeUInt32BE(Math.floor(gamma * constants.GAMMA_DIVISION), 0);
-  return this._packChunk(constants.TYPE_gAMA, buf);
-};
-
-Packer.prototype.packIHDR = function (width, height) {
-  let buf = Buffer.alloc(13);
-  buf.writeUInt32BE(width, 0);
-  buf.writeUInt32BE(height, 4);
-  buf[8] = this._options.bitDepth; // Bit depth
-  buf[9] = this._options.colorType; // colorType
-  buf[10] = 0; // compression
-  buf[11] = 0; // filter
-  buf[12] = 0; // interlace
-
-  return this._packChunk(constants.TYPE_IHDR, buf);
-};
-
-Packer.prototype.packIDAT = function (data) {
-  return this._packChunk(constants.TYPE_IDAT, data);
-};
-
-Packer.prototype.packIEND = function () {
-  return this._packChunk(constants.TYPE_IEND, null);
 };

lib/paeth-predictor.js

@@ -1,14 +0,0 @@
-export default function paethPredictor(left, above, upLeft) {
-  let paeth = left + above - upLeft;
-  let pLeft = Math.abs(paeth - left);
-  let pAbove = Math.abs(paeth - above);
-  let pUpLeft = Math.abs(paeth - upLeft);
-
-  if (pLeft <= pAbove && pLeft <= pUpLeft) {
-    return left;
-  }
-  if (pAbove <= pUpLeft) {
-    return above;
-  }
-  return upLeft;
-};

lib/parser-async.js

@@ -1,166 +0,0 @@
-import ChunkStream from "./chunkstream.js";
-import FilterAsync from "./filter-parse-async.js";
-import Parser from "./parser.js";
-import bitmapper from "./bitmapper.js";
-import formatNormaliser from "./format-normaliser.js";
-
-let util = require("util");
-let zlib = require("zlib");
-
-let ParserAsync = function (options) {
-  ChunkStream.call(this);
-
-  this._parser = new Parser(options, {
-    read: this.read.bind(this),
-    error: this._handleError.bind(this),
-    metadata: this._handleMetaData.bind(this),
-    gamma: this.emit.bind(this, "gamma"),
-    palette: this._handlePalette.bind(this),
-    transColor: this._handleTransColor.bind(this),
-    finished: this._finished.bind(this),
-    inflateData: this._inflateData.bind(this),
-    simpleTransparency: this._simpleTransparency.bind(this),
-    headersFinished: this._headersFinished.bind(this),
-  });
-  this._options = options;
-  this.writable = true;
-
-  this._parser.start();
-};
-util.inherits(ParserAsync, ChunkStream);
-
-export default ParserAsync;
-
-ParserAsync.prototype._handleError = function (err) {
-  this.emit("error", err);
-
-  this.writable = false;
-
-  this.destroy();
-
-  if (this._inflate && this._inflate.destroy) {
-    this._inflate.destroy();
-  }
-
-  if (this._filter) {
-    this._filter.destroy();
-    // For backward compatibility with Node 7 and below.
-    // Suppress errors due to _inflate calling write() even after
-    // it's destroy()'ed.
-    this._filter.on("error", function () {});
-  }
-
-  this.errord = true;
-};
-
-ParserAsync.prototype._inflateData = function (data) {
-  if (!this._inflate) {
-    if (this._bitmapInfo.interlace) {
-      this._inflate = zlib.createInflate();
-
-      this._inflate.on("error", this.emit.bind(this, "error"));
-      this._filter.on("complete", this._complete.bind(this));
-
-      this._inflate.pipe(this._filter);
-    } else {
-      let rowSize =
-        ((this._bitmapInfo.width *
-          this._bitmapInfo.bpp *
-          this._bitmapInfo.depth +
-          7) >>
-          3) +
-        1;
-      let imageSize = rowSize * this._bitmapInfo.height;
-      let chunkSize = Math.max(imageSize, zlib.Z_MIN_CHUNK);
-
-      this._inflate = zlib.createInflate({ chunkSize: chunkSize });
-      let leftToInflate = imageSize;
-
-      let emitError = this.emit.bind(this, "error");
-      this._inflate.on("error", function (err) {
-        if (!leftToInflate) {
-          return;
-        }
-
-        emitError(err);
-      });
-      this._filter.on("complete", this._complete.bind(this));
-
-      let filterWrite = this._filter.write.bind(this._filter);
-      this._inflate.on("data", function (chunk) {
-        if (!leftToInflate) {
-          return;
-        }
-
-        if (chunk.length > leftToInflate) {
-          chunk = chunk.slice(0, leftToInflate);
-        }
-
-        leftToInflate -= chunk.length;
-
-        filterWrite(chunk);
-      });
-
-      this._inflate.on("end", this._filter.end.bind(this._filter));
-    }
-  }
-  this._inflate.write(data);
-};
-
-ParserAsync.prototype._handleMetaData = function (metaData) {
-  this._metaData = metaData;
-  this._bitmapInfo = Object.create(metaData);
-
-  this._filter = new FilterAsync(this._bitmapInfo);
-};
-
-ParserAsync.prototype._handleTransColor = function (transColor) {
-  this._bitmapInfo.transColor = transColor;
-};
-
-ParserAsync.prototype._handlePalette = function (palette) {
-  this._bitmapInfo.palette = palette;
-};
-
-ParserAsync.prototype._simpleTransparency = function () {
-  this._metaData.alpha = true;
-};
-
-ParserAsync.prototype._headersFinished = function () {
-  // Up until this point, we don't know if we have a tRNS chunk (alpha)
-  // so we can't emit metadata any earlier
-  this.emit("metadata", this._metaData);
-};
-
-ParserAsync.prototype._finished = function () {
-  if (this.errord) {
-    return;
-  }
-
-  if (!this._inflate) {
-    this.emit("error", "No Inflate block");
-  } else {
-    // no more data to inflate
-    this._inflate.end();
-  }
-};
-
-ParserAsync.prototype._complete = function (filteredData) {
-  if (this.errord) {
-    return;
-  }
-
-  let normalisedBitmapData;
-
-  try {
-    let bitmapData = bitmapper(filteredData, this._bitmapInfo);
-
-    normalisedBitmapData = formatNormaliser(bitmapData, this._bitmapInfo);
-    bitmapData = null;
-  } catch (ex) {
-    this._handleError(ex);
-    return;
-  }
-
-  this.emit("parsed", normalisedBitmapData);
-};

lib/parser-sync.js

@@ -1,107 +0,0 @@
-import inflateSync from "./sync-inflate.js";
-import SyncReader from "./sync-reader.js";
-import FilterSync from "./filter-parse-sync.js";
-import bitmapper from "./bitmapper.js";
-import formatNormaliser from "./format-normaliser.js";
-import Parser from "./parser.js";
-
-let hasSyncZlib = true;
-let zlib = require("zlib");
-if (!zlib.deflateSync) {
-  hasSyncZlib = false;
-}
-
-export default function (buffer, options) {
-  if (!hasSyncZlib) {
-    throw new Error(
-      "To use the sync capability of this library in old node versions, please pin pngjs to v2.3.0"
-    );
-  }
-
-  let err;
-  function handleError(_err_) {
-    err = _err_;
-  }
-
-  let metaData;
-  function handleMetaData(_metaData_) {
-    metaData = _metaData_;
-  }
-
-  function handleTransColor(transColor) {
-    metaData.transColor = transColor;
-  }
-
-  function handlePalette(palette) {
-    metaData.palette = palette;
-  }
-
-  function handleSimpleTransparency() {
-    metaData.alpha = true;
-  }
-
-  let gamma;
-  function handleGamma(_gamma_) {
-    gamma = _gamma_;
-  }
-
-  let inflateDataList = [];
-  function handleInflateData(inflatedData) {
-    inflateDataList.push(inflatedData);
-  }
-
-  let reader = new SyncReader(buffer);
-
-  let parser = new Parser(options, {
-    read: reader.read.bind(reader),
-    error: handleError,
-    metadata: handleMetaData,
-    gamma: handleGamma,
-    palette: handlePalette,
-    transColor: handleTransColor,
-    inflateData: handleInflateData,
-    simpleTransparency: handleSimpleTransparency,
-  });
-
-  parser.start();
-  reader.process();
-
-  if (err) {
-    throw err;
-  }
-
-  //join together the inflate datas
-  let inflateData = Buffer.concat(inflateDataList);
-  inflateDataList.length = 0;
-
-  let inflatedData;
-  if (metaData.interlace) {
-    inflatedData = zlib.inflateSync(inflateData);
-  } else {
-    let rowSize =
-      ((metaData.width * metaData.bpp * metaData.depth + 7) >> 3) + 1;
-    let imageSize = rowSize * metaData.height;
-    inflatedData = inflateSync(inflateData, {
-      chunkSize: imageSize,
-      maxLength: imageSize,
-    });
-  }
-  inflateData = null;
-
-  if (!inflatedData || !inflatedData.length) {
-    throw new Error("bad png - invalid inflate data response");
-  }
-
-  let unfilteredData = FilterSync.process(inflatedData, metaData);
-  inflateData = null;
-
-  let bitmapData = bitmapper.dataToBitMap(unfilteredData, metaData);
-  unfilteredData = null;
-
-  let normalisedBitmapData = formatNormaliser(bitmapData, metaData);
-
-  metaData.data = normalisedBitmapData;
-  metaData.gamma = gamma || 0;
-
-  return metaData;
-};

lib/parser.js

@@ -1,290 +1,359 @@
-"use strict";
+// Copyright (c) 2012 Kuba Niegowski
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
 
-let constants = require("./constants");
+'use strict';
-let CrcCalculator = require("./crc");
 
-let Parser = (module.exports = function (options, dependencies) {
-  this._options = options;
-  options.checkCRC = options.checkCRC !== false;
 
-  this._hasIHDR = false;
+var util = require('util'),
-  this._hasIEND = false;
+    zlib = require('zlib'),
-  this._emittedHeadersFinished = false;
+    CrcStream = require('./crc'),
+    ChunkStream = require('./chunkstream'),
+    constants = require('./constants'),
+    Filter = require('./filter');
 
-  // input flags/metadata
-  this._palette = [];
-  this._colorType = 0;
 
-  this._chunks = {};
+var Parser = module.exports = function(options) {
-  this._chunks[constants.TYPE_IHDR] = this._handleIHDR.bind(this);
+    ChunkStream.call(this);
-  this._chunks[constants.TYPE_IEND] = this._handleIEND.bind(this);
-  this._chunks[constants.TYPE_IDAT] = this._handleIDAT.bind(this);
-  this._chunks[constants.TYPE_PLTE] = this._handlePLTE.bind(this);
-  this._chunks[constants.TYPE_tRNS] = this._handleTRNS.bind(this);
-  this._chunks[constants.TYPE_gAMA] = this._handleGAMA.bind(this);
 
-  this.read = dependencies.read;
+    this._options = options;
-  this.error = dependencies.error;
+    options.checkCRC = options.checkCRC !== false;
-  this.metadata = dependencies.metadata;
-  this.gamma = dependencies.gamma;
-  this.transColor = dependencies.transColor;
-  this.palette = dependencies.palette;
-  this.parsed = dependencies.parsed;
-  this.inflateData = dependencies.inflateData;
-  this.finished = dependencies.finished;
-  this.simpleTransparency = dependencies.simpleTransparency;
-  this.headersFinished = dependencies.headersFinished || function () {};
-});
 
-Parser.prototype.start = function () {
+    this._hasIHDR = false;
-  this.read(constants.PNG_SIGNATURE.length, this._parseSignature.bind(this));
+    this._hasIEND = false;
+
+    this._inflate = null;
+    this._filter = null;
+    this._crc = null;
+
+    // input flags/metadata
+    this._palette = [];
+    this._colorType = 0;
+
+    this._chunks = {};
+    this._chunks[constants.TYPE_IHDR] = this._handleIHDR.bind(this);
+    this._chunks[constants.TYPE_IEND] = this._handleIEND.bind(this);
+    this._chunks[constants.TYPE_IDAT] = this._handleIDAT.bind(this);
+    this._chunks[constants.TYPE_PLTE] = this._handlePLTE.bind(this);
+    this._chunks[constants.TYPE_tRNS] = this._handleTRNS.bind(this);
+    this._chunks[constants.TYPE_gAMA] = this._handleGAMA.bind(this);
+
+    this.writable = true;
+
+    this.on('error', this._handleError.bind(this));
+    this._handleSignature();
+};
+util.inherits(Parser, ChunkStream);
+
+
+Parser.prototype._handleError = function() {
+
+    this.writable = false;
+
+    this.destroy();
+
+    if (this._inflate)
+        this._inflate.destroy();
 };
 
-Parser.prototype._parseSignature = function (data) {
+Parser.prototype._handleSignature = function() {
-  let signature = constants.PNG_SIGNATURE;
+    this.read(constants.PNG_SIGNATURE.length,
+        this._parseSignature.bind(this)
+    );
+};
 
-  for (let i = 0; i < signature.length; i++) {
+Parser.prototype._parseSignature = function(data) {
-    if (data[i] !== signature[i]) {
+
-      this.error(new Error("Invalid file signature"));
+    var signature = constants.PNG_SIGNATURE;
-      return;
+
+    for (var i = 0; i < signature.length; i++) {
+        if (data[i] != signature[i]) {
+            this.emit('error', new Error('Invalid file signature'));
+            return;
+        }
     }
-  }
-  this.read(8, this._parseChunkBegin.bind(this));
-};
-
-Parser.prototype._parseChunkBegin = function (data) {
-  // chunk content length
-  let length = data.readUInt32BE(0);
-
-  // chunk type
-  let type = data.readUInt32BE(4);
-  let name = "";
-  for (let i = 4; i < 8; i++) {
-    name += String.fromCharCode(data[i]);
-  }
-
-  //console.log('chunk ', name, length);
-
-  // chunk flags
-  let ancillary = Boolean(data[4] & 0x20); // or critical
-  //    priv = Boolean(data[5] & 0x20), // or public
-  //    safeToCopy = Boolean(data[7] & 0x20); // or unsafe
-
-  if (!this._hasIHDR && type !== constants.TYPE_IHDR) {
-    this.error(new Error("Expected IHDR on beggining"));
-    return;
-  }
-
-  this._crc = new CrcCalculator();
-  this._crc.write(Buffer.from(name));
-
-  if (this._chunks[type]) {
-    return this._chunks[type](length);
-  }
-
-  if (!ancillary) {
-    this.error(new Error("Unsupported critical chunk type " + name));
-    return;
-  }
-
-  this.read(length + 4, this._skipChunk.bind(this));
-};
-
-Parser.prototype._skipChunk = function (/*data*/) {
-  this.read(8, this._parseChunkBegin.bind(this));
-};
-
-Parser.prototype._handleChunkEnd = function () {
-  this.read(4, this._parseChunkEnd.bind(this));
-};
-
-Parser.prototype._parseChunkEnd = function (data) {
-  let fileCrc = data.readInt32BE(0);
-  let calcCrc = this._crc.crc32();
-
-  // check CRC
-  if (this._options.checkCRC && calcCrc !== fileCrc) {
-    this.error(new Error("Crc error - " + fileCrc + " - " + calcCrc));
-    return;
-  }
-
-  if (!this._hasIEND) {
     this.read(8, this._parseChunkBegin.bind(this));
-  }
 };
 
-Parser.prototype._handleIHDR = function (length) {
+Parser.prototype._parseChunkBegin = function(data) {
-  this.read(length, this._parseIHDR.bind(this));
-};
-Parser.prototype._parseIHDR = function (data) {
-  this._crc.write(data);
 
-  let width = data.readUInt32BE(0);
+    // chunk content length
-  let height = data.readUInt32BE(4);
+    var length = data.readUInt32BE(0);
-  let depth = data[8];
-  let colorType = data[9]; // bits: 1 palette, 2 color, 4 alpha
-  let compr = data[10];
-  let filter = data[11];
-  let interlace = data[12];
 
-  // console.log('    width', width, 'height', height,
+    // chunk type
-  //     'depth', depth, 'colorType', colorType,
+    var type = data.readUInt32BE(4),
-  //     'compr', compr, 'filter', filter, 'interlace', interlace
+        name = '';
-  // );
+    for (var i = 4; i < 8; i++)
+        name += String.fromCharCode(data[i]);
 
-  if (
+    // console.log('chunk ', name, length);
-    depth !== 8 &&
-    depth !== 4 &&
-    depth !== 2 &&
-    depth !== 1 &&
-    depth !== 16
-  ) {
-    this.error(new Error("Unsupported bit depth " + depth));
-    return;
-  }
-  if (!(colorType in constants.COLORTYPE_TO_BPP_MAP)) {
-    this.error(new Error("Unsupported color type"));
-    return;
-  }
-  if (compr !== 0) {
-    this.error(new Error("Unsupported compression method"));
-    return;
-  }
-  if (filter !== 0) {
-    this.error(new Error("Unsupported filter method"));
-    return;
-  }
-  if (interlace !== 0 && interlace !== 1) {
-    this.error(new Error("Unsupported interlace method"));
-    return;
-  }
 
-  this._colorType = colorType;
+    // chunk flags
+    var ancillary  = !!(data[4] & 0x20),  // or critical
+        priv       = !!(data[5] & 0x20),  // or public
+        safeToCopy = !!(data[7] & 0x20);  // or unsafe
 
-  let bpp = constants.COLORTYPE_TO_BPP_MAP[this._colorType];
+    if (!this._hasIHDR && type != constants.TYPE_IHDR) {
-
+        this.emit('error', new Error('Expected IHDR on beggining'));
-  this._hasIHDR = true;
+        return;
-
-  this.metadata({
-    width: width,
-    height: height,
-    depth: depth,
-    interlace: Boolean(interlace),
-    palette: Boolean(colorType & constants.COLORTYPE_PALETTE),
-    color: Boolean(colorType & constants.COLORTYPE_COLOR),
-    alpha: Boolean(colorType & constants.COLORTYPE_ALPHA),
-    bpp: bpp,
-    colorType: colorType,
-  });
-
-  this._handleChunkEnd();
-};
-
-Parser.prototype._handlePLTE = function (length) {
-  this.read(length, this._parsePLTE.bind(this));
-};
-Parser.prototype._parsePLTE = function (data) {
-  this._crc.write(data);
-
-  let entries = Math.floor(data.length / 3);
-  // console.log('Palette:', entries);
-
-  for (let i = 0; i < entries; i++) {
-    this._palette.push([data[i * 3], data[i * 3 + 1], data[i * 3 + 2], 0xff]);
-  }
-
-  this.palette(this._palette);
-
-  this._handleChunkEnd();
-};
-
-Parser.prototype._handleTRNS = function (length) {
-  this.simpleTransparency();
-  this.read(length, this._parseTRNS.bind(this));
-};
-Parser.prototype._parseTRNS = function (data) {
-  this._crc.write(data);
-
-  // palette
-  if (this._colorType === constants.COLORTYPE_PALETTE_COLOR) {
-    if (this._palette.length === 0) {
-      this.error(new Error("Transparency chunk must be after palette"));
-      return;
     }
-    if (data.length > this._palette.length) {
+
-      this.error(new Error("More transparent colors than palette size"));
+    this._crc = new CrcStream();
-      return;
+    this._crc.write(new Buffer(name));
+
+    if (this._chunks[type]) {
+        return this._chunks[type](length);
+
+    } else if (!ancillary) {
+        this.emit('error', new Error('Unsupported critical chunk type ' + name));
+        return;
+    } else {
+        this.read(length + 4, this._skipChunk.bind(this));
     }
-    for (let i = 0; i < data.length; i++) {
+};
-      this._palette[i][3] = data[i];
+
+Parser.prototype._skipChunk = function(data) {
+    this.read(8, this._parseChunkBegin.bind(this));
+};
+
+Parser.prototype._handleChunkEnd = function() {
+    this.read(4, this._parseChunkEnd.bind(this));
+};
+
+Parser.prototype._parseChunkEnd = function(data) {
+
+    var fileCrc = data.readInt32BE(0),
+        calcCrc = this._crc.crc32();
+
+    // check CRC
+    if (this._options.checkCRC && calcCrc != fileCrc) {
+        this.emit('error', new Error('Crc error'));
+        return;
     }
-    this.palette(this._palette);
-  }
 
-  // for colorType 0 (grayscale) and 2 (rgb)
+    if (this._hasIEND) {
-  // there might be one gray/color defined as transparent
+        this.destroySoon();
-  if (this._colorType === constants.COLORTYPE_GRAYSCALE) {
-    // grey, 2 bytes
-    this.transColor([data.readUInt16BE(0)]);
-  }
-  if (this._colorType === constants.COLORTYPE_COLOR) {
-    this.transColor([
-      data.readUInt16BE(0),
-      data.readUInt16BE(2),
-      data.readUInt16BE(4),
-    ]);
-  }
 
-  this._handleChunkEnd();
+    } else {
+        this.read(8, this._parseChunkBegin.bind(this));
+    }
 };
 
-Parser.prototype._handleGAMA = function (length) {
+
-  this.read(length, this._parseGAMA.bind(this));
+Parser.prototype._handleIHDR = function(length) {
+    this.read(length, this._parseIHDR.bind(this));
 };
-Parser.prototype._parseGAMA = function (data) {
+Parser.prototype._parseIHDR = function(data) {
-  this._crc.write(data);
-  this.gamma(data.readUInt32BE(0) / constants.GAMMA_DIVISION);
 
-  this._handleChunkEnd();
+    this._crc.write(data);
-};
 
-Parser.prototype._handleIDAT = function (length) {
+    var width = data.readUInt32BE(0),
-  if (!this._emittedHeadersFinished) {
+        height = data.readUInt32BE(4),
-    this._emittedHeadersFinished = true;
+        depth = data[8],
-    this.headersFinished();
+        colorType = data[9], // bits: 1 palette, 2 color, 4 alpha
-  }
+        compr = data[10],
-  this.read(-length, this._parseIDAT.bind(this, length));
+        filter = data[11],
-};
+        interlace = data[12];
-Parser.prototype._parseIDAT = function (length, data) {
-  this._crc.write(data);
 
-  if (
+    // console.log('    width', width, 'height', height,
-    this._colorType === constants.COLORTYPE_PALETTE_COLOR &&
+    //     'depth', depth, 'colorType', colorType,
-    this._palette.length === 0
+    //     'compr', compr, 'filter', filter, 'interlace', interlace
-  ) {
+    // );
-    throw new Error("Expected palette not found");
-  }
 
-  this.inflateData(data);
+    if (depth != 8) {
-  let leftOverLength = length - data.length;
+        this.emit('error', new Error('Unsupported bit depth ' + depth));
+        return;
+    }
+    if (!(colorType in colorTypeToBppMap)) {
+        this.emit('error', new Error('Unsupported color type'));
+        return;
+    }
+    if (compr != 0) {
+        this.emit('error', new Error('Unsupported compression method'));
+        return;
+    }
+    if (filter != 0) {
+        this.emit('error', new Error('Unsupported filter method'));
+        return;
+    }
+    if (interlace != 0) {
+        this.emit('error', new Error('Unsupported interlace method'));
+        return;
+    }
+
+    this._colorType = colorType;
+
+    this._data = new Buffer(width * height * 4);
+    this._filter = new Filter(
+        width, height,
+        colorTypeToBppMap[this._colorType],
+        this._data,
+        this._options
+    );
+
+    this._hasIHDR = true;
+
+    this.emit('metadata', {
+        width: width,
+        height: height,
+        palette: !!(colorType & constants.COLOR_PALETTE),
+        color: !!(colorType & constants.COLOR_COLOR),
+        alpha: !!(colorType & constants.COLOR_ALPHA),
+        data: this._data
+    });
 
-  if (leftOverLength > 0) {
-    this._handleIDAT(leftOverLength);
-  } else {
     this._handleChunkEnd();
-  }
 };
 
-Parser.prototype._handleIEND = function (length) {
-  this.read(length, this._parseIEND.bind(this));
-};
-Parser.prototype._parseIEND = function (data) {
-  this._crc.write(data);
 
-  this._hasIEND = true;
+Parser.prototype._handlePLTE = function(length) {
-  this._handleChunkEnd();
+    this.read(length, this._parsePLTE.bind(this));
-
+};
-  if (this.finished) {
+Parser.prototype._parsePLTE = function(data) {
-    this.finished();
+
-  }
+    this._crc.write(data);
+
+    var entries = Math.floor(data.length / 3);
+    // console.log('Palette:', entries);
+
+    for (var i = 0; i < entries; i++) {
+        this._palette.push([
+            data.readUInt8(i * 3),
+            data.readUInt8(i * 3 + 1),
+            data.readUInt8(i * 3 + 2 ),
+            0xff
+        ]);
+    }
+
+    this._handleChunkEnd();
+};
+
+Parser.prototype._handleTRNS = function(length) {
+    this.read(length, this._parseTRNS.bind(this));
+};
+Parser.prototype._parseTRNS = function(data) {
+
+    this._crc.write(data);
+
+    // palette
+    if (this._colorType == 3) {
+        if (this._palette.length == 0) {
+            this.emit('error', new Error('Transparency chunk must be after palette'));
+            return;
+        }
+        if (data.length > this._palette.length) {
+            this.emit('error', new Error('More transparent colors than palette size'));
+            return;
+        }
+        for (var i = 0; i < this._palette.length; i++) {
+            this._palette[i][3] = i < data.length ? data.readUInt8(i) : 0xff;
+        }
+    }
+
+    // for colorType 0 (grayscale) and 2 (rgb)
+    // there might be one gray/color defined as transparent
+
+    this._handleChunkEnd();
+};
+
+Parser.prototype._handleGAMA = function(length) {
+    this.read(length, this._parseGAMA.bind(this));
+};
+Parser.prototype._parseGAMA = function(data) {
+
+    this._crc.write(data);
+    this.emit('gamma', data.readUInt32BE(0) / 100000);
+
+    this._handleChunkEnd();
+};
+
+Parser.prototype._handleIDAT = function(length) {
+    this.read(-length, this._parseIDAT.bind(this, length));
+};
+Parser.prototype._parseIDAT = function(length, data) {
+
+    this._crc.write(data);
+
+    if (this._colorType == 3 && this._palette.length == 0)
+        throw new Error('Expected palette not found');
+
+    if (!this._inflate) {
+        this._inflate = zlib.createInflate();
+
+        this._inflate.on('error', this.emit.bind(this, 'error'));
+        this._filter.on('complete', this._reverseFiltered.bind(this));
+
+        this._inflate.pipe(this._filter);
+    }
+
+    this._inflate.write(data);
+    length -= data.length;
+
+    if (length > 0)
+        this._handleIDAT(length);
+    else
+        this._handleChunkEnd();
+};
+
+
+Parser.prototype._handleIEND = function(length) {
+    this.read(length, this._parseIEND.bind(this));
+};
+Parser.prototype._parseIEND = function(data) {
+
+    this._crc.write(data);
+
+    // no more data to inflate
+    this._inflate.end();
+
+    this._hasIEND = true;
+    this._handleChunkEnd();
+};
+
+
+var colorTypeToBppMap = {
+    0: 1,
+    2: 3,
+    3: 1,
+    4: 2,
+    6: 4
+};
+
+Parser.prototype._reverseFiltered = function(data, width, height) {
+
+    if (this._colorType == 3) { // paletted
+
+        // use values from palette
+        var pxLineLength = width << 2;
+
+        for (var y = 0; y < height; y++) {
+            var pxRowPos = y * pxLineLength;
+
+            for (var x = 0; x < width; x++) {
+                var pxPos = pxRowPos + (x << 2),
+                    color = this._palette[data[pxPos]];
+
+                for (var i = 0; i < 4; i++)
+                    data[pxPos + i] = color[i];
+            }
+        }
+    }
+
+    this.emit('parsed', data);
 };

lib/png-sync.js

@@ -1,15 +0,0 @@
-import parse from "./parser-sync.js";
-import pack from "./packer-sync.js";
-
-export var read = function (buffer, options) {
-  return parse(buffer, options || {});
-};
-
-export var write = function (png, options) {
-  return pack(png, options);
-};
-
-export default {
-  read,
-  write
-}

lib/png.js

@@ -1,193 +1,149 @@
-import Parser from "./parser-async.js";
+// Copyright (c) 2012 Kuba Niegowski
-import Packer from "./packer-async.js";
+//
-import PNGSync from "./png-sync.js";
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
 
-let util = require("util");
+'use strict';
-let Stream = require("stream");
 
-let PNG = (exports.PNG = function (options) {
-  Stream.call(this);
 
-  options = options || {}; // eslint-disable-line no-param-reassign
+var util = require('util'),
+    Stream = require('stream'),
+    Parser = require('./parser'),
+    Packer = require('./packer');
 
-  // coerce pixel dimensions to integers (also coerces undefined -> 0):
-  this.width = options.width | 0;
-  this.height = options.height | 0;
 
-  this.data =
+var PNG = exports.PNG = function(options) {
-    this.width > 0 && this.height > 0
+    Stream.call(this);
-      ? Buffer.alloc(4 * this.width * this.height)
-      : null;
 
-  if (options.fill && this.data) {
+    options = options || {};
-    this.data.fill(0);
-  }
 
-  this.gamma = 0;
+    this.width = options.width || 0;
-  this.readable = this.writable = true;
+    this.height = options.height || 0;
 		
-  this._parser = new Parser(options);
+    this.data = this.width > 0 && this.height > 0
+            ? new Buffer(4 * this.width * this.height) : null;
 
-  this._parser.on("error", this.emit.bind(this, "error"));
+	  if(options.fill && this.data){this.data.fill(0)};
-  this._parser.on("close", this._handleClose.bind(this));
-  this._parser.on("metadata", this._metadata.bind(this));
-  this._parser.on("gamma", this._gamma.bind(this));
-  this._parser.on(
-    "parsed",
-    function (data) {
-      this.data = data;
-      this.emit("parsed", data);
-    }.bind(this)
-  );
 
-  this._packer = new Packer(options);
+    this.gamma = 0;
-  this._packer.on("data", this.emit.bind(this, "data"));
+    this.readable = this.writable = true;
-  this._packer.on("end", this.emit.bind(this, "end"));
+
-  this._parser.on("close", this._handleClose.bind(this));
+    this._parser = new Parser(options || {});
-  this._packer.on("error", this.emit.bind(this, "error"));
+
-});
+    this._parser.on('error', this.emit.bind(this, 'error'));
+    this._parser.on('close', this._handleClose.bind(this));
+    this._parser.on('metadata', this._metadata.bind(this));
+    this._parser.on('gamma', this._gamma.bind(this));
+    this._parser.on('parsed', function(data) {
+        this.data = data;
+        this.emit('parsed', data);
+    }.bind(this));
+
+    this._packer = new Packer(options);
+    this._packer.on('data', this.emit.bind(this, 'data'));
+    this._packer.on('end', this.emit.bind(this, 'end'));
+    this._parser.on('close', this._handleClose.bind(this));
+    this._packer.on('error', this.emit.bind(this, 'error'));
+
+};
 util.inherits(PNG, Stream);
 
-PNG.sync = PNGSync;
 
-PNG.prototype.pack = function () {
+PNG.prototype.pack = function() {
-  if (!this.data || !this.data.length) {
+
-    this.emit("error", "No data provided");
+    process.nextTick(function() {
+        this._packer.pack(this.data, this.width, this.height);
+    }.bind(this));
+
     return this;
-  }
-
-  process.nextTick(
-    function () {
-      this._packer.pack(this.data, this.width, this.height, this.gamma);
-    }.bind(this)
-  );
-
-  return this;
 };
 
-PNG.prototype.parse = function (data, callback) {
-  if (callback) {
-    let onParsed, onError;
 
-    onParsed = function (parsedData) {
+PNG.prototype.parse = function(data, callback) {
-      this.removeListener("error", onError);
 
-      this.data = parsedData;
+    if (callback) {
-      callback(null, this);
+        var onParsed = null, onError = null;
-    }.bind(this);
 
-    onError = function (err) {
+        this.once('parsed', onParsed = function(data) {
-      this.removeListener("parsed", onParsed);
+            this.removeListener('error', onError);
 
-      callback(err, null);
+            this.data = data;
-    }.bind(this);
+            callback(null, this);
 
-    this.once("parsed", onParsed);
+        }.bind(this));
-    this.once("error", onError);
-  }
 
-  this.end(data);
+        this.once('error', onError = function(err) {
-  return this;
+            this.removeListener('parsed', onParsed);
-};
 
-PNG.prototype.write = function (data) {
+            callback(err, null);
-  this._parser.write(data);
+        }.bind(this));
-  return true;
-};
-
-PNG.prototype.end = function (data) {
-  this._parser.end(data);
-};
-
-PNG.prototype._metadata = function (metadata) {
-  this.width = metadata.width;
-  this.height = metadata.height;
-
-  this.emit("metadata", metadata);
-};
-
-PNG.prototype._gamma = function (gamma) {
-  this.gamma = gamma;
-};
-
-PNG.prototype._handleClose = function () {
-  if (!this._parser.writable && !this._packer.readable) {
-    this.emit("close");
-  }
-};
-
-PNG.bitblt = function (src, dst, srcX, srcY, width, height, deltaX, deltaY) {
-  // eslint-disable-line max-params
-  // coerce pixel dimensions to integers (also coerces undefined -> 0):
-  /* eslint-disable no-param-reassign */
-  srcX |= 0;
-  srcY |= 0;
-  width |= 0;
-  height |= 0;
-  deltaX |= 0;
-  deltaY |= 0;
-  /* eslint-enable no-param-reassign */
-
-  if (
-    srcX > src.width ||
-    srcY > src.height ||
-    srcX + width > src.width ||
-    srcY + height > src.height
-  ) {
-    throw new Error("bitblt reading outside image");
-  }
-
-  if (
-    deltaX > dst.width ||
-    deltaY > dst.height ||
-    deltaX + width > dst.width ||
-    deltaY + height > dst.height
-  ) {
-    throw new Error("bitblt writing outside image");
-  }
-
-  for (let y = 0; y < height; y++) {
-    src.data.copy(
-      dst.data,
-      ((deltaY + y) * dst.width + deltaX) << 2,
-      ((srcY + y) * src.width + srcX) << 2,
-      ((srcY + y) * src.width + srcX + width) << 2
-    );
-  }
-};
-
-PNG.prototype.bitblt = function (
-  dst,
-  srcX,
-  srcY,
-  width,
-  height,
-  deltaX,
-  deltaY
-) {
-  // eslint-disable-line max-params
-
-  PNG.bitblt(this, dst, srcX, srcY, width, height, deltaX, deltaY);
-  return this;
-};
-
-PNG.adjustGamma = function (src) {
-  if (src.gamma) {
-    for (let y = 0; y < src.height; y++) {
-      for (let x = 0; x < src.width; x++) {
-        let idx = (src.width * y + x) << 2;
-
-        for (let i = 0; i < 3; i++) {
-          let sample = src.data[idx + i] / 255;
-          sample = Math.pow(sample, 1 / 2.2 / src.gamma);
-          src.data[idx + i] = Math.round(sample * 255);
-        }
-      }
     }
-    src.gamma = 0;
+
-  }
+    this.end(data);
+    return this;
 };
 
-PNG.prototype.adjustGamma = function () {
+PNG.prototype.write = function(data) {
-  PNG.adjustGamma(this);
+    this._parser.write(data);
+    return true;
+};
+
+PNG.prototype.end = function(data) {
+    this._parser.end(data);
+};
+
+PNG.prototype._metadata = function(metadata) {
+    this.width = metadata.width;
+    this.height = metadata.height;
+    this.data = metadata.data;
+
+    delete metadata.data;
+    this.emit('metadata', metadata);
+};
+
+PNG.prototype._gamma = function(gamma) {
+    this.gamma = gamma;
+};
+
+PNG.prototype._handleClose = function() {
+    if (!this._parser.writable && !this._packer.readable)
+        this.emit('close');
+};
+
+
+PNG.prototype.bitblt = function(dst, sx, sy, w, h, dx, dy) {
+
+    var src = this;
+
+    if (sx > src.width || sy > src.height
+            || sx + w > src.width || sy + h > src.height)
+        throw new Error('bitblt reading outside image');
+    if (dx > dst.width || dy > dst.height
+            || dx + w > dst.width || dy + h > dst.height)
+        throw new Error('bitblt writing outside image');
+
+    for (var y = 0; y < h; y++) {
+        src.data.copy(dst.data,
+            ((dy + y) * dst.width + dx) << 2,
+            ((sy + y) * src.width + sx) << 2,
+            ((sy + y) * src.width + sx + w) << 2
+        );
+    }
+
+    return this;
 };

lib/sync-inflate.js

@@ -1,163 +0,0 @@
-let assert = require("assert").ok;
-let zlib = require("zlib");
-let util = require("util");
-
-let kMaxLength = require("buffer").kMaxLength;
-
-export function Inflate(opts) {
-  if (!(this instanceof Inflate)) {
-    return new Inflate(opts);
-  }
-
-  if (opts && opts.chunkSize < zlib.Z_MIN_CHUNK) {
-    opts.chunkSize = zlib.Z_MIN_CHUNK;
-  }
-
-  zlib.Inflate.call(this, opts);
-
-  // Node 8 --> 9 compatibility check
-  this._offset = this._offset === undefined ? this._outOffset : this._offset;
-  this._buffer = this._buffer || this._outBuffer;
-
-  if (opts && opts.maxLength != null) {
-    this._maxLength = opts.maxLength;
-  }
-}
-
-export function createInflate(opts) {
-  return new Inflate(opts);
-}
-
-function _close(engine, callback) {
-  if (callback) {
-    process.nextTick(callback);
-  }
-
-  // Caller may invoke .close after a zlib error (which will null _handle).
-  if (!engine._handle) {
-    return;
-  }
-
-  engine._handle.close();
-  engine._handle = null;
-}
-
-Inflate.prototype._processChunk = function (chunk, flushFlag, asyncCb) {
-  if (typeof asyncCb === "function") {
-    return zlib.Inflate._processChunk.call(this, chunk, flushFlag, asyncCb);
-  }
-
-  let self = this;
-
-  let availInBefore = chunk && chunk.length;
-  let availOutBefore = this._chunkSize - this._offset;
-  let leftToInflate = this._maxLength;
-  let inOff = 0;
-
-  let buffers = [];
-  let nread = 0;
-
-  let error;
-  this.on("error", function (err) {
-    error = err;
-  });
-
-  function handleChunk(availInAfter, availOutAfter) {
-    if (self._hadError) {
-      return;
-    }
-
-    let have = availOutBefore - availOutAfter;
-    assert(have >= 0, "have should not go down");
-
-    if (have > 0) {
-      let out = self._buffer.slice(self._offset, self._offset + have);
-      self._offset += have;
-
-      if (out.length > leftToInflate) {
-        out = out.slice(0, leftToInflate);
-      }
-
-      buffers.push(out);
-      nread += out.length;
-      leftToInflate -= out.length;
-
-      if (leftToInflate === 0) {
-        return false;
-      }
-    }
-
-    if (availOutAfter === 0 || self._offset >= self._chunkSize) {
-      availOutBefore = self._chunkSize;
-      self._offset = 0;
-      self._buffer = Buffer.allocUnsafe(self._chunkSize);
-    }
-
-    if (availOutAfter === 0) {
-      inOff += availInBefore - availInAfter;
-      availInBefore = availInAfter;
-
-      return true;
-    }
-
-    return false;
-  }
-
-  assert(this._handle, "zlib binding closed");
-  let res;
-  do {
-    res = this._handle.writeSync(
-      flushFlag,
-      chunk, // in
-      inOff, // in_off
-      availInBefore, // in_len
-      this._buffer, // out
-      this._offset, //out_off
-      availOutBefore
-    ); // out_len
-    // Node 8 --> 9 compatibility check
-    res = res || this._writeState;
-  } while (!this._hadError && handleChunk(res[0], res[1]));
-
-  if (this._hadError) {
-    throw error;
-  }
-
-  if (nread >= kMaxLength) {
-    _close(this);
-    throw new RangeError(
-      "Cannot create final Buffer. It would be larger than 0x" +
-        kMaxLength.toString(16) +
-        " bytes"
-    );
-  }
-
-  let buf = Buffer.concat(buffers, nread);
-  _close(this);
-
-  return buf;
-};
-
-util.inherits(Inflate, zlib.Inflate);
-
-function zlibBufferSync(engine, buffer) {
-  if (typeof buffer === "string") {
-    buffer = Buffer.from(buffer);
-  }
-  if (!(buffer instanceof Buffer)) {
-    throw new TypeError("Not a string or buffer");
-  }
-
-  let flushFlag = engine._finishFlushFlag;
-  if (flushFlag == null) {
-    flushFlag = zlib.Z_FINISH;
-  }
-
-  return engine._processChunk(buffer, flushFlag);
-}
-
-export function inflateSync(buffer, opts) {
-  return zlibBufferSync(new Inflate(opts), buffer);
-}
-
-export default inflateSync;

lib/sync-reader.js

@@ -1,45 +0,0 @@
-let SyncReader = function (buffer) {
-  this._buffer = buffer;
-  this._reads = [];
-};
-
-export default SyncReader;
-
-SyncReader.prototype.read = function (length, callback) {
-  this._reads.push({
-    length: Math.abs(length), // if length < 0 then at most this length
-    allowLess: length < 0,
-    func: callback,
-  });
-};
-
-SyncReader.prototype.process = function () {
-  // as long as there is any data and read requests
-  while (this._reads.length > 0 && this._buffer.length) {
-    let read = this._reads[0];
-
-    if (
-      this._buffer.length &&
-      (this._buffer.length >= read.length || read.allowLess)
-    ) {
-      // ok there is any data so that we can satisfy this request
-      this._reads.shift(); // == read
-
-      let buf = this._buffer;
-
-      this._buffer = buf.slice(read.length);
-
-      read.func.call(this, buf.slice(0, read.length));
-    } else {
-      break;
-    }
-  }
-
-  if (this._reads.length > 0) {
-    return new Error("There are some read requests waitng on finished stream");
-  }
-
-  if (this._buffer.length > 0) {
-    return new Error("unrecognised content at end of stream");
-  }
-};

package.json

@@ -1,73 +1,29 @@
 {
-  "name": "pngjs",
+  "name": "node-png",
-  "version": "5.0.0",
+  "version": "0.4.3",
-  "description": "PNG encoder/decoder in pure JS, supporting any bit size & interlace, async & sync with full test suite.",
+  "description": "Simple PNG encoder/decoder",
-  "contributors": [
+  "author": "Kuba Niegowski",
-    "Alexandre Paré",
+  "contributors": [],
-    "Gaurav Mali",
+  "homepage": "https://github.com/niegowski/node-pngjs/",
-    "Gusts Kaksis",
-    "Kuba Niegowski",
-    "Luke Page",
-    "Pietajan De Potter",
-    "Steven Sojka",
-    "liangzeng",
-    "Michael Vogt",
-    "Xin-Xin Wang",
-    "toriningen",
-    "Eugene Kulabuhov"
-  ],
-  "homepage": "https://github.com/lukeapage/pngjs",
   "keywords": [
-    "PNG",
+    "png"
-    "decoder",
-    "encoder",
-    "js-png",
-    "node-png",
-    "parser",
-    "png",
-    "png-js",
-    "png-parse",
-    "pngjs"
   ],
   "engines": {
-    "node": ">=10.13.0"
+    "node": "0.8.x"
   },
   "main": "./lib/png.js",
   "directories": {
-    "lib": "lib",
+    "example": "examples"
-    "example": "examples",
-    "test": "test"
   },
   "scripts": {
-    "build": "yarn prepublish",
+    "test": "echo \"Error: no test specified\" && exit 1"
-    "prepublish": "yarn browserify",
-    "browserify": "browserify lib/png.js --standalone png > browser.js",
-    "coverage": "nyc --reporter=lcov --reporter=text-summary tape test/*-spec.js nolarge",
-    "test": "yarn lint && yarn prettier:check && tape test/*-spec.js | tap-dot && node test/run-compare",
-    "lint": "eslint .",
-    "prettier:write": "prettier --write .",
-    "prettier:check": "prettier --check ."
   },
   "repository": {
     "type": "git",
-    "url": "git://github.com/lukeapage/pngjs.git"
+    "url": "git://github.com/brighthas/node-pngjs.git"
   },
   "license": "MIT",
   "bugs": {
-    "url": "https://github.com/lukeapage/pngjs/issues"
+    "url": "https://github.com/brighthas/node-pngjs/issues"
-  },
-  "devDependencies": {
-    "browserify": "16.5.1",
-    "buffer-equal": "1.0.0",
-    "codecov": "3.7.0",
-    "connect": "3.7.0",
-    "eslint": "7.0.0",
-    "eslint-config-prettier": "6.11.0",
-    "nyc": "15.0.1",
-    "prettier": "2.0.5",
-    "puppeteer": "3.0.2",
-    "serve-static": "1.14.1",
-    "tap-dot": "2.0.0",
-    "tape": "5.0.0"
   }
 }

test/.gitignore

@@ -1 +0,0 @@
-bg.png

test/bg-spec.js

@@ -1,46 +0,0 @@
-#!/usr/bin/env node
-
-let fs = require("fs");
-let PNG = require("../lib/png").PNG;
-let test = require("tape");
-let bufferEqual = require("buffer-equal");
-
-test("outputs background, created from scratch", function (t) {
-  t.timeoutAfter(1000 * 60 * 5);
-
-  let png = new PNG({
-    width: 10,
-    height: 10,
-    filterType: -1,
-  });
-
-  for (let y = 0; y < png.height; y++) {
-    for (let x = 0; x < png.width; x++) {
-      let idx = (png.width * y + x) << 2;
-
-      let col = (x < png.width >> 1) ^ (y < png.height >> 1) ? 0xe5 : 0xff;
-
-      png.data[idx] = col;
-      png.data[idx + 1] = col;
-      png.data[idx + 2] = col;
-      png.data[idx + 3] = 0xff;
-    }
-  }
-
-  png
-    .pack()
-    .pipe(fs.createWriteStream(__dirname + "/bg.png"))
-    .on("finish", function () {
-      let out = fs.readFileSync(__dirname + "/bg.png");
-      let ref = fs.readFileSync(__dirname + "/bg-ref.png");
-
-      let isBufferEqual = bufferEqual(out, ref);
-      t.ok(isBufferEqual, "compares with working file ok");
-
-      if (!isBufferEqual) {
-        console.log(out.length, ref.length);
-      }
-
-      t.end();
-    });
-});

test/convert-images-spec.js

@@ -1,105 +0,0 @@
-let fs = require("fs");
-let PNG = require("../lib/png").PNG;
-let test = require("tape");
-
-let noLargeOption = process.argv.indexOf("nolarge") >= 0;
-
-fs.readdir(__dirname + "/in/", function (err, files) {
-  if (err) throw err;
-
-  files = files.filter(function (file) {
-    return (
-      (!noLargeOption || !file.match(/large/i)) &&
-      Boolean(file.match(/\.png$/i))
-    );
-  });
-
-  console.log("Converting images");
-
-  files.forEach(function (file) {
-    let expectedError = false;
-    if (file.match(/^x/)) {
-      expectedError = true;
-    }
-
-    test("convert sync - " + file, function (t) {
-      t.timeoutAfter(1000 * 60 * 5);
-
-      let data = fs.readFileSync(__dirname + "/in/" + file);
-      let png;
-      try {
-        png = PNG.sync.read(data);
-      } catch (e) {
-        if (!expectedError) {
-          t.fail(
-            "Unexpected error parsing.." +
-              file +
-              "\n" +
-              e.message +
-              "\n" +
-              e.stack
-          );
-        } else {
-          t.pass("completed");
-        }
-        return t.end();
-      }
-
-      if (expectedError) {
-        t.fail("Sync: Error expected, parsed fine .. - " + file);
-        return t.end();
-      }
-
-      let outpng = new PNG();
-      outpng.gamma = png.gamma;
-      outpng.data = png.data;
-      outpng.width = png.width;
-      outpng.height = png.height;
-      outpng.pack().pipe(
-        fs
-          .createWriteStream(__dirname + "/outsync/" + file)
-          .on("finish", function () {
-            t.pass("completed");
-            t.end();
-          })
-      );
-    });
-
-    test("convert async - " + file, function (t) {
-      t.timeoutAfter(1000 * 60 * 5);
-
-      fs.createReadStream(__dirname + "/in/" + file)
-        .pipe(new PNG())
-        .on("error", function (err) {
-          if (!expectedError) {
-            t.fail(
-              "Async: Unexpected error parsing.." +
-                file +
-                "\n" +
-                err.message +
-                "\n" +
-                err.stack
-            );
-          } else {
-            t.pass("completed");
-          }
-          t.end();
-        })
-        .on("parsed", function () {
-          if (expectedError) {
-            t.fail("Async: Error expected, parsed fine .." + file);
-            return t.end();
-          }
-
-          this.pack().pipe(
-            fs
-              .createWriteStream(__dirname + "/out/" + file)
-              .on("finish", function () {
-                t.pass("completed");
-                t.end();
-              })
-          );
-        });
-    });
-  });
-});

test/http-server.js

@@ -1,16 +0,0 @@
-let serveStatic = require("serve-static");
-let http = require("http");
-let connect = require("connect");
-
-let app = connect();
-let server = http.createServer(app);
-
-app.use(serveStatic("test"));
-
-server.listen(8000);
-
-module.exports = () => {
-  server.close();
-};
-
-console.log("Tests available at http://localhost:8000/");

test/imagediff.js

@@ -1,409 +0,0 @@
-// js-imagediff 1.0.3
-// (c) 2011-2012 Carl Sutherland, Humble Software
-// Distributed under the MIT License
-// For original source and documentation visit:
-// http://www.github.com/HumbleSoftware/js-imagediff
-
-(function (name, definition) {
-  var root = this;
-  if (typeof module !== 'undefined') {
-    try {
-      var Canvas = require('canvas');
-    } catch (e) {
-      throw new Error(
-        e.message + '\n' +
-        'Please see https://github.com/HumbleSoftware/js-imagediff#cannot-find-module-canvas\n'
-      );
-    }
-    module.exports = definition(root, name, Canvas);
-  } else if (typeof define === 'function' && typeof define.amd === 'object') {
-    define(definition);
-  } else {
-    root[name] = definition(root, name);
-  }
-})('imagediff', function (root, name, Canvas) {
-
-  var
-    TYPE_ARRAY        = /\[object Array\]/i,
-    TYPE_CANVAS       = /\[object (Canvas|HTMLCanvasElement)\]/i,
-    TYPE_CONTEXT      = /\[object CanvasRenderingContext2D\]/i,
-    TYPE_IMAGE        = /\[object (Image|HTMLImageElement)\]/i,
-    TYPE_IMAGE_DATA   = /\[object ImageData\]/i,
-
-    UNDEFINED         = 'undefined',
-
-    canvas            = getCanvas(),
-    context           = canvas.getContext('2d'),
-    previous          = root[name],
-    imagediff, jasmine;
-
-  // Creation
-  function getCanvas (width, height) {
-    var
-      canvas = Canvas ?
-        new Canvas() :
-        document.createElement('canvas');
-    if (width) canvas.width = width;
-    if (height) canvas.height = height;
-    return canvas;
-  }
-  function getImageData (width, height) {
-    canvas.width = width;
-    canvas.height = height;
-    context.clearRect(0, 0, width, height);
-    return context.createImageData(width, height);
-  }
-  // expost canvas module
-  function getCanvasRef() {
-    return Canvas;
-  }
-
-
-  // Type Checking
-  function isImage (object) {
-    return isType(object, TYPE_IMAGE);
-  }
-  function isCanvas (object) {
-    return isType(object, TYPE_CANVAS);
-  }
-  function isContext (object) {
-    return isType(object, TYPE_CONTEXT);
-  }
-  function isImageData (object) {
-    return !!(object &&
-      isType(object, TYPE_IMAGE_DATA) &&
-      typeof(object.width) !== UNDEFINED &&
-      typeof(object.height) !== UNDEFINED &&
-      typeof(object.data) !== UNDEFINED);
-  }
-  function isImageType (object) {
-    return (
-      isImage(object) ||
-      isCanvas(object) ||
-      isContext(object) ||
-      isImageData(object)
-    );
-  }
-  function isType (object, type) {
-    return typeof (object) === 'object' && !!Object.prototype.toString.apply(object).match(type);
-  }
-
-
-  // Type Conversion
-  function copyImageData (imageData) {
-    var
-      height = imageData.height,
-      width = imageData.width,
-      data = imageData.data,
-      newImageData, newData, i;
-
-    canvas.width = width;
-    canvas.height = height;
-    newImageData = context.getImageData(0, 0, width, height);
-    newData = newImageData.data;
-
-    for (i = imageData.data.length; i--;) {
-        newData[i] = data[i];
-    }
-
-    return newImageData;
-  }
-  function toImageData (object) {
-    if (isImage(object)) { return toImageDataFromImage(object); }
-    if (isCanvas(object)) { return toImageDataFromCanvas(object); }
-    if (isContext(object)) { return toImageDataFromContext(object); }
-    if (isImageData(object)) { return object; }
-  }
-  function toImageDataFromImage (image) {
-    var
-      height = image.height,
-      width = image.width;
-    canvas.width = width;
-    canvas.height = height;
-    context.clearRect(0, 0, width, height);
-    context.drawImage(image, 0, 0);
-    return context.getImageData(0, 0, width, height);
-  }
-  function toImageDataFromCanvas (canvas) {
-    var
-      height = canvas.height,
-      width = canvas.width,
-      context = canvas.getContext('2d');
-    return context.getImageData(0, 0, width, height);
-  }
-  function toImageDataFromContext (context) {
-    var
-      canvas = context.canvas,
-      height = canvas.height,
-      width = canvas.width;
-    return context.getImageData(0, 0, width, height);
-  }
-  function toCanvas (object) {
-    var
-      data = toImageData(object),
-      canvas = getCanvas(data.width, data.height),
-      context = canvas.getContext('2d');
-
-    context.putImageData(data, 0, 0);
-    return canvas;
-  }
-
-
-  // ImageData Equality Operators
-  function equalWidth (a, b) {
-    return a.width === b.width;
-  }
-  function equalHeight (a, b) {
-    return a.height === b.height;
-  }
-  function equalDimensions (a, b) {
-    return equalHeight(a, b) && equalWidth(a, b);
-  }
-  function equal (a, b, tolerance) {
-
-    var
-      aData     = a.data,
-      bData     = b.data,
-      length    = aData.length,
-      i;
-
-    tolerance = tolerance || 0;
-
-    if (!equalDimensions(a, b)) return false;
-    for (i = length; i--;) {
-      if (aData[i] !== bData[i] && Math.abs(aData[i] - bData[i]) > tolerance) {
-        var x = i % (a.width * 4);
-        var y = (i - x) / (a.width * 4);
-        var color = x % 4;
-        x = (x - color) / 4;
-        console.log("Difference x", x, "y", y, ["R", "G", "B", "A"][color], "  -  ", aData[i], " !== ", bData[i]);
-        return false;
-      }
-    }
-
-    return true;
-  }
-
-
-  // Diff
-  function diff (a, b, options) {
-    return (equalDimensions(a, b) ? diffEqual : diffUnequal)(a, b, options);
-  }
-  function diffEqual (a, b, options) {
-
-    var
-      height  = a.height,
-      width   = a.width,
-      c       = getImageData(width, height), // c = a - b
-      aData   = a.data,
-      bData   = b.data,
-      cData   = c.data,
-      length  = cData.length,
-      row, column,
-      i, j, k, v;
-
-    for (i = 0; i < length; i += 4) {
-      cData[i] = Math.abs(aData[i] - bData[i]);
-      cData[i+1] = Math.abs(aData[i+1] - bData[i+1]);
-      cData[i+2] = Math.abs(aData[i+2] - bData[i+2]);
-      cData[i+3] = Math.abs(255 - Math.abs(aData[i+3] - bData[i+3]));
-    }
-
-    return c;
-  }
-  function diffUnequal (a, b, options) {
-
-    var
-      height  = Math.max(a.height, b.height),
-      width   = Math.max(a.width, b.width),
-      c       = getImageData(width, height), // c = a - b
-      aData   = a.data,
-      bData   = b.data,
-      cData   = c.data,
-      align   = options && options.align,
-      rowOffset,
-      columnOffset,
-      row, column,
-      i, j, k, v;
-
-
-    for (i = cData.length - 1; i > 0; i = i - 4) {
-      cData[i] = 255;
-    }
-
-    // Add First Image
-    offsets(a);
-    for (row = a.height; row--;){
-      for (column = a.width; column--;) {
-        i = 4 * ((row + rowOffset) * width + (column + columnOffset));
-        j = 4 * (row * a.width + column);
-        cData[i+0] = aData[j+0]; // r
-        cData[i+1] = aData[j+1]; // g
-        cData[i+2] = aData[j+2]; // b
-        // cData[i+3] = aData[j+3]; // a
-      }
-    }
-
-    // Subtract Second Image
-    offsets(b);
-    for (row = b.height; row--;){
-      for (column = b.width; column--;) {
-        i = 4 * ((row + rowOffset) * width + (column + columnOffset));
-        j = 4 * (row * b.width + column);
-        cData[i+0] = Math.abs(cData[i+0] - bData[j+0]); // r
-        cData[i+1] = Math.abs(cData[i+1] - bData[j+1]); // g
-        cData[i+2] = Math.abs(cData[i+2] - bData[j+2]); // b
-      }
-    }
-
-    // Helpers
-    function offsets (imageData) {
-      if (align === 'top') {
-        rowOffset = 0;
-        columnOffset = 0;
-      } else {
-        rowOffset = Math.floor((height - imageData.height) / 2);
-        columnOffset = Math.floor((width - imageData.width) / 2);
-      }
-    }
-
-    return c;
-  }
-
-
-  // Validation
-  function checkType () {
-    var i;
-    for (i = 0; i < arguments.length; i++) {
-      if (!isImageType(arguments[i])) {
-        throw {
-          name : 'ImageTypeError',
-          message : 'Submitted object was not an image.'
-        };
-      }
-    }
-  }
-
-
-  // Jasmine Matchers
-  function get (element, content) {
-    element = document.createElement(element);
-    if (element && content) {
-      element.innerHTML = content;
-    }
-    return element;
-  }
-
-  jasmine = {
-
-    toBeImageData : function () {
-      return imagediff.isImageData(this.actual);
-    },
-
-    toImageDiffEqual : function (expected, tolerance) {
-
-      if (typeof (document) !== UNDEFINED) {
-        this.message = function () {
-          var
-            div     = get('div'),
-            a       = get('div', '<div>Actual:</div>'),
-            b       = get('div', '<div>Expected:</div>'),
-            c       = get('div', '<div>Diff:</div>'),
-            diff    = imagediff.diff(this.actual, expected),
-            canvas  = getCanvas(),
-            context;
-
-          canvas.height = diff.height;
-          canvas.width  = diff.width;
-
-          div.style.overflow = 'hidden';
-          a.style.float = 'left';
-          b.style.float = 'left';
-          c.style.float = 'left';
-
-          context = canvas.getContext('2d');
-          context.putImageData(diff, 0, 0);
-
-          a.appendChild(toCanvas(this.actual));
-          b.appendChild(toCanvas(expected));
-          c.appendChild(canvas);
-
-          div.appendChild(a);
-          div.appendChild(b);
-          div.appendChild(c);
-
-          return [
-            div,
-            "Expected not to be equal."
-          ];
-        };
-      }
-
-      return imagediff.equal(this.actual, expected, tolerance);
-    }
-  };
-
-
-  // Image Output
-  function imageDataToPNG (imageData, outputFile, callback) {
-
-    var
-      canvas = toCanvas(imageData),
-      base64Data,
-      decodedImage;
-
-    callback = callback || Function;
-
-    base64Data = canvas.toDataURL().replace(/^data:image\/\w+;base64,/,"");
-    decodedImage = Buffer.from(base64Data, 'base64');
-    require('fs').writeFile(outputFile, decodedImage, callback);
-  }
-
-
-  // Definition
-  imagediff = {
-
-    createCanvas : getCanvas,
-    createImageData : getImageData,
-    getCanvasRef: getCanvasRef,
-
-    isImage : isImage,
-    isCanvas : isCanvas,
-    isContext : isContext,
-    isImageData : isImageData,
-    isImageType : isImageType,
-
-    toImageData : function (object) {
-      checkType(object);
-      if (isImageData(object)) { return copyImageData(object); }
-      return toImageData(object);
-    },
-
-    equal : function (a, b, tolerance) {
-      checkType(a, b);
-      a = toImageData(a);
-      b = toImageData(b);
-      return equal(a, b, tolerance);
-    },
-    diff : function (a, b, options) {
-      checkType(a, b);
-      a = toImageData(a);
-      b = toImageData(b);
-      return diff(a, b, options);
-    },
-
-    jasmine : jasmine,
-
-    // Compatibility
-    noConflict : function () {
-      root[name] = previous;
-      return imagediff;
-    }
-  };
-
-  if (typeof module !== 'undefined') {
-    imagediff.imageDataToPNG = imageDataToPNG;
-  }
-
-  return imagediff;
-});