readme

README.md

@@ -1,10 +1,108 @@
-PNG.js
+About
 ========
+Simple PNG encoder/decoder for Node.js with no native dependencies.
 
+Installation
+===============
+```
+$ npm install pngjs
+```
 
-Options
---------
+Example
+==========
+```js
+var fs = require('fs'),
+    PNG = require('pngjs').PNG;
+
+var png = new PNG({
+        filterType: 4
+    }),
+    src = fs.createReadStream(process.argv[2]),
+    dst = fs.createWriteStream(process.argv[3]);
+
+png.on('parsed', function() {
+
+    for (var y = 0; y < png.height; y++) {
+        for (var x = 0; x < png.width; x++) {
+            var idx = (png.width * y + x) << 2;
+
+            // invert color
+            png.data[idx] = 255 - png.data[idx];
+            png.data[idx+1] = 255 - png.data[idx+1];
+            png.data[idx+2] = 255 - png.data[idx+2];
+
+            // and reduce opacity
+            png.data[idx+3] = png.data[idx+3] >> 1;
+        }
+    }
+
+    png.pack();
+});
+
+src.pipe(png).pipe(dst);
+```
+For more examples see `examples` folder.
+
+Documentation
+================
+
+## PNG
+`PNG` is readable and writeable `Stream`.
+
+### Options
+- `width` - `int`
+- `height` - `int`
 - `checkCRC` - `boolean` default: `true`
 - `deflateChunkSize` - `int` default: 32 kB
 - `deflateLevel` - `int` default: 9
 - `filterType` - `int` default: -1 (auto)
+
+### Event: "parsed"
+`function(data) { }`
+
+### png.pack()
+Starts converting data to PNG file Stream
+
+### png.parse(data, [callback])
+Parses PNG file data. Alternatively you can stream data to PNG.
+
+Optional `callback` is once called on `error` or `parsed`. The callback gets
+two arguments `(err, data)`.
+
+### Property: width
+
+### Property: height
+
+### Property: data
+Buffer of image pixel data. Every pixel consists 4 bytes: R, G, B, A (opacity).
+
+Changelog
+============
+
+### 0.1.0-alpha - 19 Aug 2012
+  - First version
+
+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
+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.