pngjs/lib/parser-sync.js

'use strict';


var zlib = require('zlib');
var SyncReader = require('./sync-reader');
var FilterSync = require('./filter-sync');
var Parser = require('./parser');
var bitmapper = require('./bitmapper');
var formatNormaliser = require('./format-normaliser');


var ParserSync = module.exports = function(buffer, options) {

  var reader = new SyncReader(buffer);

  this._inflateDataList = [];
  this._parser = new Parser(options, {
    read: reader.read.bind(reader),
    error: this._handleError.bind(this),
    metadata: this._metaData.bind(this),
    gamma: this._gamma.bind(this),
    finished: function() {
    },
    inflateData: this._inflateData.bind(this),
    createData: this._createData.bind(this)
  });
  this._options = options;

  this._parser.start();
  reader.process();

  //join together the inflate datas
  var inflateData = Buffer.concat(this._inflateDataList);

  var data = zlib.inflateSync(inflateData);

  if (!data || !data.length) {
    throw new Error('bad png - invalid inflate data response');
  }

  data = FilterSync.process(
    data,
    this._width, this._height,
    this._bpp,
    this._depth,
    this._interlace,
    this._options
  );
// todo do not store _data
  this._data = bitmapper.dataToBitMap(data, this._width, this._height,
    this._bpp,
    this._depth,
    this._interlace);

  this.data = formatNormaliser(this._data, {
    depth: this._depth, // TODO always store in this format
    width: this._width,
    height: this._height,
    colorType: this._parser._colorType,
    palette: this._parser._palette,
    transColor: this._parser._transColor });
};

ParserSync.prototype._handleError = function(err) {
  this.err = err;
};

ParserSync.prototype._metaData = function(metaData) {
  this.metaData = metaData;
};

ParserSync.prototype._gamma = function(gamma) {
  this.gamma = gamma;
};

ParserSync.prototype._inflateData = function(data) {
  this._inflateDataList.push(data);
};

ParserSync.prototype._createData = function(width, height, bpp, depth, interlace) {
  this._data = new Buffer(width * height * 4);
  this._bpp = bpp;
  this._width = width;
  this._height = height;
  this._depth = depth;
  this._interlace = interlace;
  return this._data; // todo do not return
};