// Generated by CoffeeScript 1.4.0
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/*
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# MIT LICENSE
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# Copyright (c) 2011 Devon Govett
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#
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# Permission is hereby granted, free of charge, to any person obtaining a copy of this
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# software and associated documentation files (the "Software"), to deal in the Software
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# without restriction, including without limitation the rights to use, copy, modify, merge,
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# publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons
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# to whom the Software is furnished to do so, subject to the following conditions:
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#
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# The above copyright notice and this permission notice shall be included in all copies or
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# substantial portions of the Software.
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#
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# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
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# BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
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# DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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*/
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(function() {
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var PNG;
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PNG = (function() {
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var APNG_BLEND_OP_OVER, APNG_BLEND_OP_SOURCE, APNG_DISPOSE_OP_BACKGROUND, APNG_DISPOSE_OP_NONE, APNG_DISPOSE_OP_PREVIOUS, makeImage, scratchCanvas, scratchCtx;
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PNG.load = function(url, canvas, callback) {
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var xhr,
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_this = this;
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if (typeof canvas === 'function') {
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callback = canvas;
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}
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xhr = new XMLHttpRequest;
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xhr.open("GET", url, true);
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xhr.responseType = "arraybuffer";
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xhr.onload = function() {
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var data, png;
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data = new Uint8Array(xhr.response || xhr.mozResponseArrayBuffer);
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png = new PNG(data);
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if (typeof (canvas != null ? canvas.getContext : void 0) === 'function') {
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png.render(canvas);
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}
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return typeof callback === "function" ? callback(png) : void 0;
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};
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return xhr.send(null);
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};
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APNG_DISPOSE_OP_NONE = 0;
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APNG_DISPOSE_OP_BACKGROUND = 1;
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APNG_DISPOSE_OP_PREVIOUS = 2;
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APNG_BLEND_OP_SOURCE = 0;
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APNG_BLEND_OP_OVER = 1;
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function PNG(data) {
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var chunkSize, colors, delayDen, delayNum, frame, i, index, key, section, short, text, _i, _j, _ref;
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this.data = data;
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this.pos = 8;
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this.palette = [];
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this.imgData = [];
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this.transparency = {};
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this.animation = null;
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this.text = {};
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frame = null;
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while (true) {
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chunkSize = this.readUInt32();
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section = ((function() {
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var _i, _results;
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_results = [];
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for (i = _i = 0; _i < 4; i = ++_i) {
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_results.push(String.fromCharCode(this.data[this.pos++]));
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}
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return _results;
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}).call(this)).join('');
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switch (section) {
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case 'IHDR':
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this.width = this.readUInt32();
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this.height = this.readUInt32();
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this.bits = this.data[this.pos++];
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this.colorType = this.data[this.pos++];
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this.compressionMethod = this.data[this.pos++];
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this.filterMethod = this.data[this.pos++];
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this.interlaceMethod = this.data[this.pos++];
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break;
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case 'acTL':
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this.animation = {
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numFrames: this.readUInt32(),
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numPlays: this.readUInt32() || Infinity,
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frames: []
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};
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break;
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case 'PLTE':
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this.palette = this.read(chunkSize);
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break;
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case 'fcTL':
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if (frame) {
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this.animation.frames.push(frame);
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}
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this.pos += 4;
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frame = {
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width: this.readUInt32(),
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height: this.readUInt32(),
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xOffset: this.readUInt32(),
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yOffset: this.readUInt32()
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};
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delayNum = this.readUInt16();
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delayDen = this.readUInt16() || 100;
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frame.delay = 1000 * delayNum / delayDen;
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frame.disposeOp = this.data[this.pos++];
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frame.blendOp = this.data[this.pos++];
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frame.data = [];
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break;
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case 'IDAT':
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case 'fdAT':
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if (section === 'fdAT') {
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this.pos += 4;
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chunkSize -= 4;
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}
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data = (frame != null ? frame.data : void 0) || this.imgData;
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for (i = _i = 0; 0 <= chunkSize ? _i < chunkSize : _i > chunkSize; i = 0 <= chunkSize ? ++_i : --_i) {
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data.push(this.data[this.pos++]);
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}
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break;
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case 'tRNS':
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this.transparency = {};
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switch (this.colorType) {
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case 3:
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this.transparency.indexed = this.read(chunkSize);
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short = 255 - this.transparency.indexed.length;
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if (short > 0) {
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for (i = _j = 0; 0 <= short ? _j < short : _j > short; i = 0 <= short ? ++_j : --_j) {
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this.transparency.indexed.push(255);
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}
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}
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break;
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case 0:
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this.transparency.grayscale = this.read(chunkSize)[0];
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break;
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case 2:
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this.transparency.rgb = this.read(chunkSize);
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}
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break;
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case 'tEXt':
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text = this.read(chunkSize);
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index = text.indexOf(0);
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key = String.fromCharCode.apply(String, text.slice(0, index));
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this.text[key] = String.fromCharCode.apply(String, text.slice(index + 1));
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break;
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case 'IEND':
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if (frame) {
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this.animation.frames.push(frame);
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}
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this.colors = (function() {
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switch (this.colorType) {
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case 0:
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case 3:
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case 4:
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return 1;
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case 2:
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case 6:
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return 3;
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}
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}).call(this);
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this.hasAlphaChannel = (_ref = this.colorType) === 4 || _ref === 6;
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colors = this.colors + (this.hasAlphaChannel ? 1 : 0);
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this.pixelBitlength = this.bits * colors;
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this.colorSpace = (function() {
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switch (this.colors) {
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case 1:
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return 'DeviceGray';
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case 3:
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return 'DeviceRGB';
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}
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}).call(this);
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this.imgData = new Uint8Array(this.imgData);
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return;
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default:
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this.pos += chunkSize;
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}
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this.pos += 4;
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if (this.pos > this.data.length) {
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throw new Error("Incomplete or corrupt PNG file");
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}
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}
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return;
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}
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PNG.prototype.read = function(bytes) {
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var i, _i, _results;
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_results = [];
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for (i = _i = 0; 0 <= bytes ? _i < bytes : _i > bytes; i = 0 <= bytes ? ++_i : --_i) {
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_results.push(this.data[this.pos++]);
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}
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return _results;
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};
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PNG.prototype.readUInt32 = function() {
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var b1, b2, b3, b4;
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b1 = this.data[this.pos++] << 24;
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b2 = this.data[this.pos++] << 16;
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b3 = this.data[this.pos++] << 8;
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b4 = this.data[this.pos++];
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return b1 | b2 | b3 | b4;
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};
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PNG.prototype.readUInt16 = function() {
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var b1, b2;
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b1 = this.data[this.pos++] << 8;
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b2 = this.data[this.pos++];
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return b1 | b2;
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};
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PNG.prototype.decodePixels = function(data) {
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var byte, c, col, i, left, length, p, pa, paeth, pb, pc, pixelBytes, pixels, pos, row, scanlineLength, upper, upperLeft, _i, _j, _k, _l, _m;
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if (data == null) {
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data = this.imgData;
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}
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if (data.length === 0) {
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return new Uint8Array(0);
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}
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data = new FlateStream(data);
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data = data.getBytes();
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pixelBytes = this.pixelBitlength / 8;
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scanlineLength = pixelBytes * this.width;
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pixels = new Uint8Array(scanlineLength * this.height);
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length = data.length;
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row = 0;
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pos = 0;
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c = 0;
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while (pos < length) {
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switch (data[pos++]) {
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case 0:
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for (i = _i = 0; _i < scanlineLength; i = _i += 1) {
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pixels[c++] = data[pos++];
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}
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break;
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case 1:
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for (i = _j = 0; _j < scanlineLength; i = _j += 1) {
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byte = data[pos++];
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left = i < pixelBytes ? 0 : pixels[c - pixelBytes];
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pixels[c++] = (byte + left) % 256;
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}
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break;
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case 2:
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for (i = _k = 0; _k < scanlineLength; i = _k += 1) {
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byte = data[pos++];
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col = (i - (i % pixelBytes)) / pixelBytes;
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upper = row && pixels[(row - 1) * scanlineLength + col * pixelBytes + (i % pixelBytes)];
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pixels[c++] = (upper + byte) % 256;
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}
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break;
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case 3:
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for (i = _l = 0; _l < scanlineLength; i = _l += 1) {
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byte = data[pos++];
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col = (i - (i % pixelBytes)) / pixelBytes;
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left = i < pixelBytes ? 0 : pixels[c - pixelBytes];
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upper = row && pixels[(row - 1) * scanlineLength + col * pixelBytes + (i % pixelBytes)];
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pixels[c++] = (byte + Math.floor((left + upper) / 2)) % 256;
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}
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break;
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case 4:
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for (i = _m = 0; _m < scanlineLength; i = _m += 1) {
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byte = data[pos++];
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col = (i - (i % pixelBytes)) / pixelBytes;
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left = i < pixelBytes ? 0 : pixels[c - pixelBytes];
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if (row === 0) {
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upper = upperLeft = 0;
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} else {
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upper = pixels[(row - 1) * scanlineLength + col * pixelBytes + (i % pixelBytes)];
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upperLeft = col && pixels[(row - 1) * scanlineLength + (col - 1) * pixelBytes + (i % pixelBytes)];
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}
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p = left + upper - upperLeft;
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pa = Math.abs(p - left);
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pb = Math.abs(p - upper);
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pc = Math.abs(p - upperLeft);
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if (pa <= pb && pa <= pc) {
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paeth = left;
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} else if (pb <= pc) {
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paeth = upper;
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} else {
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paeth = upperLeft;
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}
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pixels[c++] = (byte + paeth) % 256;
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}
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break;
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default:
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throw new Error("Invalid filter algorithm: " + data[pos - 1]);
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}
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row++;
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}
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return pixels;
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};
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PNG.prototype.decodePalette = function() {
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var c, i, length, palette, pos, ret, transparency, _i, _ref, _ref1;
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palette = this.palette;
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transparency = this.transparency.indexed || [];
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ret = new Uint8Array((transparency.length || 0) + palette.length);
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pos = 0;
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length = palette.length;
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c = 0;
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for (i = _i = 0, _ref = palette.length; _i < _ref; i = _i += 3) {
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ret[pos++] = palette[i];
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ret[pos++] = palette[i + 1];
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ret[pos++] = palette[i + 2];
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ret[pos++] = (_ref1 = transparency[c++]) != null ? _ref1 : 255;
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}
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return ret;
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};
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PNG.prototype.copyToImageData = function(imageData, pixels) {
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var alpha, colors, data, i, input, j, k, length, palette, v, _ref;
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colors = this.colors;
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palette = null;
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alpha = this.hasAlphaChannel;
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if (this.palette.length) {
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palette = (_ref = this._decodedPalette) != null ? _ref : this._decodedPalette = this.decodePalette();
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colors = 4;
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alpha = true;
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}
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data = imageData.data || imageData;
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length = data.length;
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input = palette || pixels;
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i = j = 0;
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if (colors === 1) {
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while (i < length) {
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k = palette ? pixels[i / 4] * 4 : j;
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v = input[k++];
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data[i++] = v;
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data[i++] = v;
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data[i++] = v;
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data[i++] = alpha ? input[k++] : 255;
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j = k;
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}
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} else {
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while (i < length) {
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k = palette ? pixels[i / 4] * 4 : j;
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data[i++] = input[k++];
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data[i++] = input[k++];
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data[i++] = input[k++];
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data[i++] = alpha ? input[k++] : 255;
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j = k;
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}
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}
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};
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PNG.prototype.decode = function() {
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var ret;
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ret = new Uint8Array(this.width * this.height * 4);
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this.copyToImageData(ret, this.decodePixels());
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return ret;
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};
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//scratchCanvas = document.createElement('canvas');
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//scratchCtx = scratchCanvas.getContext('2d');
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makeImage = function(imageData) {
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var img;
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scratchCtx.width = imageData.width;
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scratchCtx.height = imageData.height;
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scratchCtx.clearRect(0, 0, imageData.width, imageData.height);
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scratchCtx.putImageData(imageData, 0, 0);
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img = new Image;
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img.src = scratchCanvas.toDataURL();
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return img;
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};
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PNG.prototype.decodeFrames = function(ctx) {
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var frame, i, imageData, pixels, _i, _len, _ref, _results;
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if (!this.animation) {
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return;
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}
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_ref = this.animation.frames;
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_results = [];
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for (i = _i = 0, _len = _ref.length; _i < _len; i = ++_i) {
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frame = _ref[i];
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imageData = ctx.createImageData(frame.width, frame.height);
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pixels = this.decodePixels(new Uint8Array(frame.data));
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this.copyToImageData(imageData, pixels);
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frame.imageData = imageData;
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_results.push(frame.image = makeImage(imageData));
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}
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return _results;
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};
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PNG.prototype.renderFrame = function(ctx, number) {
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var frame, frames, prev;
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frames = this.animation.frames;
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frame = frames[number];
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prev = frames[number - 1];
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if (number === 0) {
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ctx.clearRect(0, 0, this.width, this.height);
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}
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if ((prev != null ? prev.disposeOp : void 0) === APNG_DISPOSE_OP_BACKGROUND) {
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ctx.clearRect(prev.xOffset, prev.yOffset, prev.width, prev.height);
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} else if ((prev != null ? prev.disposeOp : void 0) === APNG_DISPOSE_OP_PREVIOUS) {
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ctx.putImageData(prev.imageData, prev.xOffset, prev.yOffset);
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}
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if (frame.blendOp === APNG_BLEND_OP_SOURCE) {
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ctx.clearRect(frame.xOffset, frame.yOffset, frame.width, frame.height);
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}
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return ctx.drawImage(frame.image, frame.xOffset, frame.yOffset);
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};
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PNG.prototype.animate = function(ctx) {
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var doFrame, frameNumber, frames, numFrames, numPlays, _ref,
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_this = this;
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frameNumber = 0;
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_ref = this.animation, numFrames = _ref.numFrames, frames = _ref.frames, numPlays = _ref.numPlays;
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return (doFrame = function() {
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var f, frame;
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f = frameNumber++ % numFrames;
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frame = frames[f];
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_this.renderFrame(ctx, f);
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if (numFrames > 1 && frameNumber / numFrames < numPlays) {
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return _this.animation._timeout = setTimeout(doFrame, frame.delay);
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}
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})();
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};
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PNG.prototype.stopAnimation = function() {
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var _ref;
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return clearTimeout((_ref = this.animation) != null ? _ref._timeout : void 0);
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};
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PNG.prototype.render = function(canvas) {
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var ctx, data;
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if (canvas._png) {
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canvas._png.stopAnimation();
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}
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canvas._png = this;
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canvas.width = this.width;
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canvas.height = this.height;
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ctx = canvas.getContext("2d");
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if (this.animation) {
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this.decodeFrames(ctx);
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return this.animate(ctx);
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} else {
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data = ctx.createImageData(this.width, this.height);
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this.copyToImageData(data, this.decodePixels());
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return ctx.putImageData(data, 0, 0);
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}
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};
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return PNG;
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})();
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this.PNG = PNG;
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})
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.call(this);
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