From 219aad8ea57538868c6735860dbcc0873f62dcd8 Mon Sep 17 00:00:00 2001 From: Julie Lala Date: Wed, 29 Jan 2014 09:31:53 -0500 Subject: grunt build process for worker --- js/worker/GIFEncoder.js | 513 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 513 insertions(+) create mode 100755 js/worker/GIFEncoder.js (limited to 'js/worker/GIFEncoder.js') diff --git a/js/worker/GIFEncoder.js b/js/worker/GIFEncoder.js new file mode 100755 index 0000000..01d3618 --- /dev/null +++ b/js/worker/GIFEncoder.js @@ -0,0 +1,513 @@ +/** +* This class lets you encode animated GIF files +* Base class : http://www.java2s.com/Code/Java/2D-Graphics-GUI/AnimatedGifEncoder.htm +* @author Kevin Weiner (original Java version - kweiner@fmsware.com) +* @author Thibault Imbert (AS3 version - bytearray.org) +* @version 0.1 AS3 implementation +*/ + +//import flash.utils.ByteArray; +//import flash.display.BitmapData; +//import flash.display.Bitmap; +//import org.bytearray.gif.encoder.NeuQuant +//import flash.net.URLRequestHeader; +//import flash.net.URLRequestMethod; +//import flash.net.URLRequest; +//import flash.net.navigateToURL; + +GIFEncoder = function() { + for(var i = 0, chr = {}; i < 256; i++) { + chr[i] = String.fromCharCode(i); + } + + function ByteArray(){ + this.bin = []; + } + + ByteArray.prototype.getData = function(){ + for(var v = '', l = this.bin.length, i = 0; i < l; i++) { + v += chr[this.bin[i]]; + } + return v; + } + ByteArray.prototype.writeByte = function(val){ + this.bin.push(val); + } + ByteArray.prototype.writeUTFBytes = function(string) { + for(var l = string.length, i = 0; i < l; i++) { + this.writeByte(string.charCodeAt(i)); + } + } + ByteArray.prototype.writeBytes = function(array, offset, length) { + for(var l = length || array.length, i = offset||0; i < l; i++) { + this.writeByte(array[i]); + } + } + + var exports = {}; + var width/*int*/ // image size + var height/*int*/; + var transparent/***/ = null; // transparent color if given + var transIndex/*int*/; // transparent index in color table + var repeat/*int*/ = -1; // no repeat + var delay/*int*/ = 0; // frame delay (hundredths) + var started/*Boolean*/ = false; // ready to output frames + var out/*ByteArray*/; + var image/*Bitmap*/; // current frame + var pixels/*ByteArray*/; // BGR byte array from frame + var indexedPixels/*ByteArray*/ // converted frame indexed to palette + var colorDepth/*int*/; // number of bit planes + var colorTab/*ByteArray*/; // RGB palette + var usedEntry/*Array*/ = new Array; // active palette entries + var palSize/*int*/ = 7; // color table size (bits-1) + var dispose/*int*/ = -1; // disposal code (-1 = use default) + var closeStream/*Boolean*/ = false; // close stream when finished + var firstFrame/*Boolean*/ = true; + var sizeSet/*Boolean*/ = false; // if false, get size from first frame + var sample/*int*/ = 1; // default sample interval for quantizer + var neuquantBrain = null; // allow loading in a prefab neural net + + /** + * Sets the delay time between each frame, or changes it for subsequent frames + * (applies to last frame added) + * int delay time in milliseconds + * @param ms + */ + + var setDelay = exports.setDelay = function setDelay(ms/*int*/) { + delay = Math.round(ms / 10); + } + + /** + * Sets the GIF frame disposal code for the last added frame and any + * + * subsequent frames. Default is 0 if no transparent color has been set, + * otherwise 2. + * @param code + * int disposal code. + */ + + var setDispose = exports.setDispose = function setDispose(code/*int*/) { + if (code >= 0) dispose = code; + } + + /** + * Sets the number of times the set of GIF frames should be played. Default is + * 1; 0 means play indefinitely. Must be invoked before the first image is + * added. + * + * @param iter + * int number of iterations. + * @return + */ + + var setRepeat = exports.setRepeat = function setRepeat(iter/*int*/) { + if (iter >= 0) repeat = iter; + } + + /** + * Sets the transparent color for the last added frame and any subsequent + * frames. Since all colors are subject to modification in the quantization + * process, the color in the final palette for each frame closest to the given + * color becomes the transparent color for that frame. May be set to null to + * indicate no transparent color. + * @param + * Color to be treated as transparent on display. + */ + + var setTransparent = exports.setTransparent = function setTransparent(c/*Number*/) { + transparent = c; + } + + /** + * The addFrame method takes an incoming BitmapData object to create each frames + * @param + * BitmapData object to be treated as a GIF's frame + */ + + /*Boolean*/ + var addFrame = exports.addFrame = function addFrame(im/*BitmapData*/, is_imageData) { + if ((im == null) || ! started || out == null) { + throw new Error ("Please call start method before calling addFrame"); + return false; + } + + var ok/*Boolean*/ = true; + + try { + if ( ! is_imageData) { + image = im.getImageData(0,0, im.canvas.width, im.canvas.height).data; + if ( ! sizeSet) { + setSize(im.canvas.width, im.canvas.height); + } + } + else { + image = im; + } + getImagePixels(); // convert to correct format if necessary + analyzePixels(); // build color table & map pixels + + if (firstFrame) { + writeLSD(); // logical screen descriptior + writePalette(); // global color table + if (repeat >= 0) { + // use NS app extension to indicate reps + writeNetscapeExt(); + } + } + + writeGraphicCtrlExt(); // write graphic control extension + writeImageDesc(); // image descriptor + if (!firstFrame) { + writePalette(); // local color table + } + writePixels(); // encode and write pixel data + firstFrame = false; + } + catch (e/*Error*/) { + ok = false; + } + return ok; + } + + /** + * Adds final trailer to the GIF stream, if you don't call the finish method + * the GIF stream will not be valid. + */ + + /*Boolean*/ + var finish = exports.finish = function finish() { + if ( ! started) { + return false; + } + + var ok/*Boolean*/ = true; + started = false; + try { + out.writeByte(0x3b); // gif trailer + } + catch (e/*Error*/) { + ok = false; + } + return ok; + } + + /** + * Resets some members so that a new stream can be started. + * This method is actually called by the start method + */ + + var reset = function reset () { + // reset for subsequent use + transIndex = 0; + image = null; + pixels = null; + indexedPixels = null; + colorTab = null; + closeStream = false; + firstFrame = true; + } + + /** + * * Sets frame rate in frames per second. Equivalent to + * setDelay(1000/fps). + * @param fps + * float frame rate (frames per second) + */ + + var setFrameRate = exports.setFrameRate = function setFrameRate(fps/*Number*/) { + if (fps != 0xf) { + delay = Math.round(100/fps); + } + } + + /** + * Sets quality of color quantization (conversion of images to the maximum 256 + * colors allowed by the GIF specification). Lower values (minimum = 1) + * produce better colors, but slow processing significantly. 10 is the + * default, and produces good color mapping at reasonable speeds. Values + * greater than 20 do not yield significant improvements in speed. + * @param quality + * int greater than 0. + * @return + */ + + var setQuality = exports.setQuality = function setQuality(quality/*int*/) { + sample = Math.max(1, quality); + } + + /** + * Sets the GIF frame size. The default size is the size of the first frame + * added if this method is not invoked. + * @param w + * int frame width. + * @param h + * int frame width. + */ + + var setSize = exports.setSize = function setSize(w/*int*/, h/*int*/) { + if (started && !firstFrame) { + return; + } + width = w; + height = h; + if (width < 1) width = 320; + if (height < 1) height = 240; + sizeSet = true; + } + + /** + * After running the Neuquant on some test frames, it can be exported and then loaded + * into an uninitialized NQ instance on another worker and used accordingly. + */ + var setNeuquant = exports.setNeuquant = function setNeuquant(neuquant, colors){ + neuquantBrain = neuquant; + colorTab = colors; + } + + /** + * Initiates GIF file creation on the given stream. + * @param os + * OutputStream on which GIF images are written. + * @return false if initial write failed. + */ + + var start = exports.start = function start() { + reset(); + var ok/*Boolean*/ = true; + closeStream = false; + out = new ByteArray; + try { + out.writeUTFBytes("GIF89a"); // header + } catch (e/*Error*/) { + ok = false; + } + + return started = ok; + } + + var cont = exports.cont = function cont() { + reset(); + var ok = true; + closeStream = false; + out = new ByteArray (); + return started = ok; + } + + /** + * Analyzes image colors and creates color map. + */ + + var analyzePixels = function analyzePixels() { + var len = pixels.length; + var nPix = len / 3; + indexedPixels = []; + // initialize quantizer + + var nq; + if (neuquantBrain && colorTab) { + nq = new NeuQuant(); + nq.load(neuquantBrain); + } + else { + nq = new NeuQuant (pixels, len, sample); + colorTab = nq.process(); // create reduced palette + } + + // map image pixels to new palette + var k = 0; + for (var j = 0; j < nPix; j++) { + var index = nq.map(pixels[k++] & 0xff, pixels[k++] & 0xff, pixels[k++] & 0xff); + usedEntry[index] = true; + indexedPixels[j] = index; + } + pixels = null; + colorDepth = 8; + palSize = 7; + + // get closest match to transparent color if specified + if (transparent != null) { + transIndex = findClosest(transparent); + } + } + + /** + * Returns index of palette color closest to c + */ + + var findClosest = function findClosest(c/*Number*/) { + if (colorTab == null) return -1; + var r = (c & 0xFF0000) >> 16; + var g = (c & 0x00FF00) >> 8; + var b = (c & 0x0000FF); + var minpos = 0; + var dmin = 256 * 256 * 256; + var len = colorTab.length; + + for (var i = 0; i < len;) { + var dr = r - (colorTab[i++] & 0xff); + var dg = g - (colorTab[i++] & 0xff); + var db = b - (colorTab[i] & 0xff); + var d = dr * dr + dg * dg + db * db; + var index = i / 3; + if (usedEntry[index] && (d < dmin)) { + dmin = d; + minpos = index; + } + i++; + } + return minpos; + } + + /** + * Extracts image pixels into byte array "pixels + */ + + var getImagePixels = function getImagePixels() { + var w = width; + var h = height; + pixels = []; + var data = image; + var count/*int*/ = 0; + + for ( var i/*int*/ = 0; i < h; i++ ) { + for (var j/*int*/ = 0; j < w; j++ ) { + var b = (i*w*4)+j*4; + pixels[count++] = data[b]; + pixels[count++] = data[b+1]; + pixels[count++] = data[b+2]; + } + } + } + + /** + * Writes Graphic Control Extension + */ + + var writeGraphicCtrlExt = function writeGraphicCtrlExt() { + out.writeByte(0x21); // extension introducer + out.writeByte(0xf9); // GCE label + out.writeByte(4); // data block size + var transp/*int*/ + var disp/*int*/; + if (transparent == null) { + transp = 0; + disp = 0; // dispose = no action + } + else { + transp = 1; + disp = 2; // force clear if using transparent color + } + if (dispose >= 0) { + disp = dispose & 7; // user override + } + disp <<= 2; + // packed fields + out.writeByte(0 | // 1:3 reserved + disp | // 4:6 disposal + 0 | // 7 user input - 0 = none + transp); // 8 transparency flag + + WriteShort(delay); // delay x 1/100 sec + out.writeByte(transIndex); // transparent color index + out.writeByte(0); // block terminator + } + + /** + * Writes Image Descriptor + */ + + var writeImageDesc = function writeImageDesc() { + out.writeByte(0x2c); // image separator + WriteShort(0); // image position x,y = 0,0 + WriteShort(0); + WriteShort(width); // image size + WriteShort(height); + + // packed fields + if (firstFrame) { + // no LCT - GCT is used for first (or only) frame + out.writeByte(0); + } + else { + // specify normal LCT + out.writeByte(0x80 | // 1 local color table 1=yes + 0 | // 2 interlace - 0=no + 0 | // 3 sorted - 0=no + 0 | // 4-5 reserved + palSize); // 6-8 size of color table + } + } + + /** + * Writes Logical Screen Descriptor + */ + + var writeLSD = function writeLSD() { + // logical screen size + WriteShort(width); + WriteShort(height); + // packed fields + out.writeByte((0x80 | // 1 : global color table flag = 1 (gct used) + 0x70 | // 2-4 : color resolution = 7 + 0x00 | // 5 : gct sort flag = 0 + palSize)); // 6-8 : gct size + + out.writeByte(0); // background color index + out.writeByte(0); // pixel aspect ratio - assume 1:1 + } + + /** + * Writes Netscape application extension to define repeat count. + */ + + var writeNetscapeExt = function writeNetscapeExt() { + out.writeByte(0x21); // extension introducer + out.writeByte(0xff); // app extension label + out.writeByte(11); // block size + out.writeUTFBytes("NETSCAPE" + "2.0"); // app id + auth code + out.writeByte(3); // sub-block size + out.writeByte(1); // loop sub-block id + WriteShort(repeat); // loop count (extra iterations, 0=repeat forever) + out.writeByte(0); // block terminator + } + + /** + * Writes color table + */ + var writePalette = function writePalette() { + out.writeBytes(colorTab); + var n/*int*/ = (3 * 256) - colorTab.length; + for (var i/*int*/ = 0; i < n; i++) { + out.writeByte(0); + } + } + + var WriteShort = function WriteShort (pValue/*int*/) { + out.writeByte( pValue & 0xFF ); + out.writeByte( (pValue >> 8) & 0xFF); + } + + /** + * Encodes and writes pixel data + */ + var writePixels = function writePixels() { + var myencoder = new LZWEncoder(width, height, indexedPixels, colorDepth); + myencoder.encode(out); + } + + /** + * retrieves the GIF stream + */ + var stream = exports.stream = function stream () { + return out; + } + + var setProperties = exports.setProperties = function setProperties(has_start, is_first) { + started = has_start; + firstFrame = is_first; + } + + return exports; +} + -- cgit v1.2.3-70-g09d2