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niandeng
@@ -0,0 +1,868 @@
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/**
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* This class lets you decode animated GIF files, and show animated GIF's in the Flash player
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* Base Class : http://www.java2s.com/Code/Java/2D-Graphics-GUI/GiffileEncoder.htm
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* @author Kevin Weiner (original Java version - kweiner@fmsware.com)
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* @author Thibault Imbert (AS3 version - bytearray.org)
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* @version 0.1 AS3 implementation
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*/
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package org.bytearray.gif.decoder
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{
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import flash.display.Bitmap;
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import flash.display.BitmapData;
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import flash.geom.Rectangle;
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import flash.utils.ByteArray;
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import org.bytearray.gif.errors.FileTypeError;
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import org.bytearray.gif.frames.GIFFrame;
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public class GIFDecoder
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{
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/**
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* File read status: No errors.
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*/
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private static var STATUS_OK:int = 0;
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/**
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* File read status: Error decoding file (may be partially decoded)
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*/
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private static var STATUS_FORMAT_ERROR:int = 1;
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/**
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* File read status: Unable to open source.
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*/
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private static var STATUS_OPEN_ERROR:int = 2;
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private static var frameRect:Rectangle = new Rectangle;
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private var inStream:ByteArray;
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private var status:int;
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// full image width
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private var width:int;
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// full image height
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private var height:int;
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// global color table used
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private var gctFlag:Boolean;
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// size of global color table
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private var gctSize:int;
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// iterations; 0 = repeat forever
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private var loopCount:int = 1;
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// global color table
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private var gct:Array;
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// local color table
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private var lct:Array;
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// active color table
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private var act:Array;
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// background color index
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private var bgIndex:int;
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// background color
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private var bgColor:int;
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// previous bg color
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private var lastBgColor:int;
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// pixel aspect ratio
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private var pixelAspect:int;
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private var lctFlag:Boolean // local color table flag
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// interlace flag
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private var interlace:Boolean;
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// local color table size
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private var lctSize:int;
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private var ix:int;
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private var iy:int;
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private var iw:int;
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// current image rectangle
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private var ih:int;
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// last image rect
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private var lastRect:Rectangle;
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// current frame
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private var image:BitmapData;
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private var bitmap:BitmapData;
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// previous frame
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private var lastImage:BitmapData;
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// current data block
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private var block:ByteArray;
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// block size
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private var blockSize:int = 0;
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// last graphic control extension info
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private var dispose:int= 0;
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// 0=no action; 1=leave in place; 2=restore to bg; 3=restore to prev
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private var lastDispose:int = 0;
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// use transparent color
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private var transparency:Boolean = false;
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// delay in milliseconds
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private var delay:int = 0;
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// transparent color index
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private var transIndex:int;
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// max decoder pixel stack size
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private static var MaxStackSize:int = 4096;
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// LZW decoder working arrays
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private var prefix:Array
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private var suffix:Array;
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private var pixelStack:Array;
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private var pixels:Array;
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// frames read from current file
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private var frames:Array
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private var frameCount:int
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public function GIFDecoder ( )
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{
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block = new ByteArray;
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}
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public function get disposeValue():int
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{
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return dispose;
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}
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/**
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* Gets display duration for specified frame.
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*
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* @param n int index of frame
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* @return delay in milliseconds
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*/
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public function getDelay(n:int):int
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{
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delay = -1;
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if ((n >= 0) && (n < frameCount))
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{
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delay = frames[n].delay;
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}
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return delay;
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}
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/**
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* Gets the number of frames read from file.
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* @return frame count
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*/
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public function getFrameCount():int
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{
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return frameCount;
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}
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/**
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* Gets the first (or only) image read.
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*
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* @return BitmapData containing first frame, or null if none.
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*/
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public function getImage():GIFFrame
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{
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return getFrame(0);
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}
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/**
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* Gets the "Netscape" iteration count, if any.
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* A count of 0 means repeat indefinitiely.
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*
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* @return iteration count if one was specified, else 1.
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*/
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public function getLoopCount():int
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{
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return loopCount;
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}
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/**
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* Creates new frame image from current data (and previous
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* frames as specified by their disposition codes).
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*/
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private function getPixels( bitmap:BitmapData ):Array
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{
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var pixels:Array = new Array ( 4 * image.width * image.height );
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var count:int = 0;
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var lngWidth:int = image.width;
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var lngHeight:int = image.height;
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var color:int;
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for (var th:int = 0; th < lngHeight; th++)
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{
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for (var tw:int = 0; tw < lngWidth; tw++)
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{
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color = bitmap.getPixel (th, tw);
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pixels[count++] = (color & 0xFF0000) >> 16;
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pixels[count++] = (color & 0x00FF00) >> 8;
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pixels[count++] = (color & 0x0000FF);
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}
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}
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return pixels;
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}
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private function setPixels( pixels:Array ):void
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{
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var count:int = 0;
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var color:int;
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pixels.position = 0;
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var lngWidth:int = image.width;
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var lngHeight:int = image.height;
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bitmap.lock();
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for (var th:int = 0; th < lngHeight; th++)
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{
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for (var tw:int = 0; tw < lngWidth; tw++)
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{
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color = pixels[int(count++)];
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bitmap.setPixel32 ( tw, th, color );
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}
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}
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bitmap.unlock();
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}
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private function transferPixels():void
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{
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// expose destination image's pixels as int array
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var dest:Array = getPixels( bitmap );
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// fill in starting image contents based on last image's dispose code
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if (lastDispose > 0)
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{
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if (lastDispose == 3)
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{
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// use image before last
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var n:int = frameCount - 2;
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lastImage = n > 0 ? getFrame(n - 1).bitmapData : null;
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}
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if (lastImage != null)
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{
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var prev:Array = getPixels( lastImage );
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dest = prev.slice();
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// copy pixels
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if (lastDispose == 2)
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{
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// fill last image rect area with background color
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var c:Number;
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// assume background is transparent
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c = transparency ? 0x00000000 : lastBgColor;
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// use given background color
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image.fillRect( lastRect, c );
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}
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}
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}
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// copy each source line to the appropriate place in the destination
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var pass:int = 1;
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var inc:int = 8;
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var iline:int = 0;
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for (var i:int = 0; i < ih; i++)
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{
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var line:int = i;
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if (interlace)
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{
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if (iline >= ih)
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{
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pass++;
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switch (pass)
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{
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case 2 :
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iline = 4;
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break;
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case 3 :
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iline = 2;
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inc = 4;
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break;
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case 4 :
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iline = 1;
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inc = 2;
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break;
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}
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}
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line = iline;
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iline += inc;
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}
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line += iy;
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if (line < height)
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{
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var k:int = line * width;
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var dx:int = k + ix; // start of line in dest
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var dlim:int = dx + iw; // end of dest line
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if ((k + width) < dlim)
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{
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dlim = k + width; // past dest edge
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}
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var sx:int = i * iw; // start of line in source
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var index:int;
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var tmp:int;
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while (dx < dlim)
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{
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// map color and insert in destination
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index = (pixels[sx++]) & 0xff;
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tmp = act[index];
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if (tmp != 0)
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{
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dest[dx] = tmp;
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}
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dx++;
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}
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}
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}
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setPixels( dest );
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}
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/**
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* Gets the image contents of frame n.
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*
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* @return BufferedImage representation of frame, or null if n is invalid.
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*/
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public function getFrame(n:int):GIFFrame
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{
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var im:GIFFrame = null;
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if ((n >= 0) && (n < frameCount))
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{
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im =frames[n];
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} else throw new RangeError ("Wrong frame number passed");
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return im;
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}
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/**
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* Gets image size.
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*
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* @return GIF image dimensions
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*/
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public function getFrameSize():Rectangle
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{
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var rect:Rectangle = GIFDecoder.frameRect;
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rect.x = rect.y = 0; rect.width = width; rect.height = height;
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return rect;
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}
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/**
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* Reads GIF image from stream
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*
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* @param BufferedInputStream containing GIF file.
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* @return read status code (0 = no errors)
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*/
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public function read( inStream:ByteArray ):int
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{
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init();
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if ( inStream != null)
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{
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this.inStream = inStream;
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readHeader();
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if (!hasError())
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{
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readContents();
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if (frameCount < 0) status = STATUS_FORMAT_ERROR;
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}
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}
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else
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{
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status = STATUS_OPEN_ERROR;
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}
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return status;
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}
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/**
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* Decodes LZW image data into pixel array.
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* Adapted from John Cristy's ImageMagick.
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*/
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private function decodeImageData():void
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{
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var NullCode:int = -1;
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var npix:int = iw * ih;
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var available:int;
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var clear:int;
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var code_mask:int;
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var code_size:int;
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var end_of_information:int;
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var in_code:int;
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var old_code:int;
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var bits:int;
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var code:int;
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var count:int;
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var i:int;
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var datum:int;
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var data_size:int;
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var first:int;
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var top:int;
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var bi:int;
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var pi:int;
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if ((pixels == null) || (pixels.length < npix))
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{
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pixels = new Array ( npix ); // allocate new pixel array
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}
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if (prefix == null) prefix = new Array ( MaxStackSize );
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if (suffix == null) suffix = new Array ( MaxStackSize );
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if (pixelStack == null) pixelStack = new Array ( MaxStackSize + 1 );
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// Initialize GIF data stream decoder.
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data_size = readSingleByte();
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clear = 1 << data_size;
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end_of_information = clear + 1;
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available = clear + 2;
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old_code = NullCode;
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code_size = data_size + 1;
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code_mask = (1 << code_size) - 1;
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for (code = 0; code < clear; code++)
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{
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prefix[int(code)] = 0;
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suffix[int(code)] = code;
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}
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// Decode GIF pixel stream.
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datum = bits = count = first = top = pi = bi = 0;
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for (i = 0; i < npix;)
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{
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if (top == 0)
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{
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if (bits < code_size)
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{
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// Load bytes until there are enough bits for a code.
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if (count == 0)
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{
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// Read a new data block.
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count = readBlock();
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if (count <= 0)
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break;
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bi = 0;
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}
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datum += (int((block[int(bi)])) & 0xff) << bits;
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bits += 8;
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bi++;
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count--;
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continue;
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}
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// Get the next code.
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code = datum & code_mask;
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datum >>= code_size;
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bits -= code_size;
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// Interpret the code
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if ((code > available) || (code == end_of_information))
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break;
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if (code == clear)
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{
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// Reset decoder.
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code_size = data_size + 1;
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code_mask = (1 << code_size) - 1;
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available = clear + 2;
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old_code = NullCode;
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continue;
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}
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if (old_code == NullCode)
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{
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pixelStack[int(top++)] = suffix[int(code)];
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old_code = code;
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first = code;
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continue;
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}
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in_code = code;
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if (code == available)
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{
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pixelStack[int(top++)] = first;
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code = old_code;
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}
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while (code > clear)
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{
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pixelStack[int(top++)] = suffix[int(code)];
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code = prefix[int(code)];
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}
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first = (suffix[int(code)]) & 0xff;
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// Add a new string to the string table,
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if (available >= MaxStackSize) break;
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pixelStack[int(top++)] = first;
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prefix[int(available)] = old_code;
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suffix[int(available)] = first;
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available++;
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if (((available & code_mask) == 0)
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&& (available < MaxStackSize))
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{
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code_size++;
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code_mask += available;
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}
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old_code = in_code;
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}
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// Pop a pixel off the pixel stack.
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top--;
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pixels[int(pi++)] = pixelStack[int(top)];
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i++;
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}
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||||
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for (i = pi; i < npix; i++)
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||||
{
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pixels[int(i)] = 0; // clear missing pixels
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||||
}
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||||
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||||
}
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||||
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||||
/**
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* Returns true if an error was encountered during reading/decoding
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||||
*/
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||||
private function hasError():Boolean
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||||
{
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return status != STATUS_OK;
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}
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||||
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||||
/**
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* Initializes or re-initializes reader
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||||
*/
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private function init():void
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||||
{
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status = STATUS_OK;
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frameCount = 0;
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||||
frames = new Array;
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||||
gct = null;
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lct = null;
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}
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||||
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/**
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* Reads a single byte from the input stream.
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*/
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||||
private function readSingleByte():int
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||||
{
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var curByte:int = 0;
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try
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||||
{
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||||
curByte = inStream.readUnsignedByte();
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||||
}
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||||
catch (e:Error)
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||||
{
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||||
status = STATUS_FORMAT_ERROR;
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||||
}
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||||
return curByte;
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||||
}
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||||
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||||
/**
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||||
* Reads next variable length block from input.
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||||
*
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||||
* @return number of bytes stored in "buffer"
|
||||
*/
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||||
private function readBlock():int
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||||
{
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||||
blockSize = readSingleByte();
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||||
var n:int = 0;
|
||||
if (blockSize > 0)
|
||||
{
|
||||
try
|
||||
{
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||||
var count:int = 0;
|
||||
while (n < blockSize)
|
||||
{
|
||||
|
||||
inStream.readBytes(block, n, blockSize - n);
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||||
if ( (blockSize - n) == -1)
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||||
break;
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||||
n += (blockSize - n);
|
||||
}
|
||||
}
|
||||
catch (e:Error)
|
||||
{
|
||||
}
|
||||
|
||||
if (n < blockSize)
|
||||
{
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||||
status = STATUS_FORMAT_ERROR;
|
||||
}
|
||||
}
|
||||
return n;
|
||||
}
|
||||
|
||||
/**
|
||||
* Reads color table as 256 RGB integer values
|
||||
*
|
||||
* @param ncolors int number of colors to read
|
||||
* @return int array containing 256 colors (packed ARGB with full alpha)
|
||||
*/
|
||||
private function readColorTable(ncolors:int):Array
|
||||
{
|
||||
var nbytes:int = 3 * ncolors;
|
||||
var tab:Array = null;
|
||||
var c:ByteArray = new ByteArray;
|
||||
var n:int = 0;
|
||||
try
|
||||
{
|
||||
inStream.readBytes(c, 0, nbytes );
|
||||
n = nbytes;
|
||||
}
|
||||
catch (e:Error)
|
||||
{
|
||||
}
|
||||
if (n < nbytes)
|
||||
{
|
||||
status = STATUS_FORMAT_ERROR;
|
||||
}
|
||||
else
|
||||
{
|
||||
tab = new Array(256); // max size to avoid bounds checks
|
||||
var i:int = 0;
|
||||
var j:int = 0;
|
||||
while (i < ncolors)
|
||||
{
|
||||
var r:int = (c[j++]) & 0xff;
|
||||
var g:int = (c[j++]) & 0xff;
|
||||
var b:int = (c[j++]) & 0xff;
|
||||
tab[i++] = ( 0xff000000 | (r << 16) | (g << 8) | b );
|
||||
}
|
||||
}
|
||||
return tab;
|
||||
}
|
||||
|
||||
/**
|
||||
* Main file parser. Reads GIF content blocks.
|
||||
*/
|
||||
private function readContents():void
|
||||
{
|
||||
// read GIF file content blocks
|
||||
var done:Boolean = false;
|
||||
|
||||
while (!(done || hasError()))
|
||||
{
|
||||
|
||||
var code:int = readSingleByte();
|
||||
|
||||
switch (code)
|
||||
{
|
||||
|
||||
case 0x2C : // image separator
|
||||
readImage();
|
||||
break;
|
||||
|
||||
case 0x21 : // extension
|
||||
code = readSingleByte();
|
||||
switch (code)
|
||||
{
|
||||
case 0xf9 : // graphics control extension
|
||||
readGraphicControlExt();
|
||||
break;
|
||||
|
||||
case 0xff : // application extension
|
||||
readBlock();
|
||||
var app:String = "";
|
||||
for (var i:int = 0; i < 11; i++)
|
||||
{
|
||||
app += block[int(i)];
|
||||
}
|
||||
if (app == "NETSCAPE2.0")
|
||||
{
|
||||
readNetscapeExt();
|
||||
}
|
||||
else
|
||||
skip(); // don't care
|
||||
break;
|
||||
|
||||
default : // uninteresting extension
|
||||
skip();
|
||||
break;
|
||||
}
|
||||
break;
|
||||
|
||||
case 0x3b : // terminator
|
||||
done = true;
|
||||
break;
|
||||
|
||||
case 0x00 : // bad byte, but keep going and see what happens
|
||||
break;
|
||||
|
||||
default :
|
||||
status = STATUS_FORMAT_ERROR;
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Reads Graphics Control Extension values
|
||||
*/
|
||||
private function readGraphicControlExt():void
|
||||
{
|
||||
readSingleByte(); // block size
|
||||
var packed:int = readSingleByte(); // packed fields
|
||||
dispose = (packed & 0x1c) >> 2; // disposal method
|
||||
if (dispose == 0)
|
||||
{
|
||||
dispose = 1; // elect to keep old image if discretionary
|
||||
}
|
||||
transparency = (packed & 1) != 0;
|
||||
delay = readShort() * 10; // delay in milliseconds
|
||||
transIndex = readSingleByte(); // transparent color index
|
||||
readSingleByte(); // block terminator
|
||||
}
|
||||
|
||||
/**
|
||||
* Reads GIF file header information.
|
||||
*/
|
||||
private function readHeader():void
|
||||
{
|
||||
var id:String = "";
|
||||
for (var i:int = 0; i < 6; i++)
|
||||
{
|
||||
id += String.fromCharCode (readSingleByte());
|
||||
|
||||
}
|
||||
if (!( id.indexOf("GIF") == 0 ) )
|
||||
{
|
||||
status = STATUS_FORMAT_ERROR;
|
||||
throw new FileTypeError ( "Invalid file type" );
|
||||
return;
|
||||
}
|
||||
readLSD();
|
||||
if (gctFlag && !hasError())
|
||||
{
|
||||
gct = readColorTable(gctSize);
|
||||
bgColor = gct[bgIndex];
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Reads next frame image
|
||||
*/
|
||||
private function readImage():void
|
||||
{
|
||||
ix = readShort(); // (sub)image position & size
|
||||
iy = readShort();
|
||||
iw = readShort();
|
||||
ih = readShort();
|
||||
|
||||
var packed:int = readSingleByte();
|
||||
lctFlag = (packed & 0x80) != 0; // 1 - local color table flag
|
||||
interlace = (packed & 0x40) != 0; // 2 - interlace flag
|
||||
// 3 - sort flag
|
||||
// 4-5 - reserved
|
||||
lctSize = 2 << (packed & 7); // 6-8 - local color table size
|
||||
|
||||
if (lctFlag)
|
||||
{
|
||||
lct = readColorTable(lctSize); // read table
|
||||
act = lct; // make local table active
|
||||
}
|
||||
else
|
||||
{
|
||||
act = gct; // make global table active
|
||||
if (bgIndex == transIndex)
|
||||
bgColor = 0;
|
||||
}
|
||||
var save:int = 0;
|
||||
if (transparency)
|
||||
{
|
||||
save = act[transIndex];
|
||||
act[transIndex] = 0; // set transparent color if specified
|
||||
}
|
||||
|
||||
if (act == null)
|
||||
{
|
||||
status = STATUS_FORMAT_ERROR; // no color table defined
|
||||
}
|
||||
|
||||
if (hasError()) return;
|
||||
|
||||
decodeImageData(); // decode pixel data
|
||||
skip();
|
||||
if (hasError()) return;
|
||||
|
||||
frameCount++;
|
||||
// create new image to receive frame data
|
||||
|
||||
bitmap = new BitmapData ( width, height );
|
||||
|
||||
image = bitmap;
|
||||
|
||||
transferPixels(); // transfer pixel data to image
|
||||
|
||||
frames.push ( new GIFFrame (bitmap, delay) ); // add image to frame list
|
||||
|
||||
if (transparency) act[transIndex] = save;
|
||||
|
||||
resetFrame();
|
||||
|
||||
}
|
||||
|
||||
/**
|
||||
* Reads Logical Screen Descriptor
|
||||
*/
|
||||
private function readLSD():void
|
||||
{
|
||||
|
||||
// logical screen size
|
||||
width = readShort();
|
||||
height = readShort();
|
||||
|
||||
// packed fields
|
||||
var packed:int = readSingleByte();
|
||||
|
||||
gctFlag = (packed & 0x80) != 0; // 1 : global color table flag
|
||||
// 2-4 : color resolution
|
||||
// 5 : gct sort flag
|
||||
gctSize = 2 << (packed & 7); // 6-8 : gct size
|
||||
bgIndex = readSingleByte(); // background color index
|
||||
pixelAspect = readSingleByte(); // pixel aspect ratio
|
||||
|
||||
}
|
||||
|
||||
/**
|
||||
* Reads Netscape extenstion to obtain iteration count
|
||||
*/
|
||||
private function readNetscapeExt():void
|
||||
{
|
||||
do
|
||||
{
|
||||
readBlock();
|
||||
if (block[0] == 1)
|
||||
{
|
||||
// loop count sub-block
|
||||
var b1:int = (block[1]) & 0xff;
|
||||
var b2:int = (block[2]) & 0xff;
|
||||
loopCount = (b2 << 8) | b1;
|
||||
}
|
||||
} while ((blockSize > 0) && !hasError());
|
||||
}
|
||||
|
||||
/**
|
||||
* Reads next 16-bit value, LSB first
|
||||
*/
|
||||
private function readShort():int
|
||||
{
|
||||
// read 16-bit value, LSB first
|
||||
return readSingleByte() | (readSingleByte() << 8);
|
||||
}
|
||||
|
||||
/**
|
||||
* Resets frame state for reading next image.
|
||||
*/
|
||||
private function resetFrame():void
|
||||
{
|
||||
lastDispose = dispose;
|
||||
lastRect = new Rectangle(ix, iy, iw, ih);
|
||||
lastImage = image;
|
||||
lastBgColor = bgColor;
|
||||
// int dispose = 0;
|
||||
var transparency:Boolean = false;
|
||||
var delay:int = 0;
|
||||
lct = null;
|
||||
}
|
||||
|
||||
/**
|
||||
* Skips variable length blocks up to and including
|
||||
* next zero length block.
|
||||
*/
|
||||
private function skip():void
|
||||
{
|
||||
do
|
||||
{
|
||||
readBlock();
|
||||
|
||||
} while ((blockSize > 0) && !hasError());
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
@@ -0,0 +1,514 @@
|
||||
/**
|
||||
* 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
|
||||
*/
|
||||
|
||||
package org.bytearray.gif.encoder
|
||||
{
|
||||
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;
|
||||
|
||||
public class GIFEncoder
|
||||
{
|
||||
private var width:int // image size
|
||||
private var height:int;
|
||||
private var transparent:* = null; // transparent color if given
|
||||
private var transIndex:int; // transparent index in color table
|
||||
private var repeat:int = -1; // no repeat
|
||||
private var delay:int = 0; // frame delay (hundredths)
|
||||
private var started:Boolean = false; // ready to output frames
|
||||
private var out:ByteArray;
|
||||
private var image:Bitmap; // current frame
|
||||
private var pixels:ByteArray; // BGR byte array from frame
|
||||
private var indexedPixels:ByteArray // converted frame indexed to palette
|
||||
private var colorDepth:int; // number of bit planes
|
||||
private var colorTab:ByteArray; // RGB palette
|
||||
private var usedEntry:Array = new Array; // active palette entries
|
||||
private var palSize:int = 7; // color table size (bits-1)
|
||||
private var dispose:int = -1; // disposal code (-1 = use default)
|
||||
private var closeStream:Boolean = false; // close stream when finished
|
||||
private var firstFrame:Boolean = true;
|
||||
private var sizeSet:Boolean = false; // if false, get size from first frame
|
||||
private var sample:int = 10; // default sample interval for quantizer
|
||||
|
||||
/**
|
||||
* 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
|
||||
*/
|
||||
|
||||
public function setDelay(ms:int):void
|
||||
{
|
||||
|
||||
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.
|
||||
*/
|
||||
|
||||
public function setDispose(code:int):void
|
||||
{
|
||||
|
||||
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
|
||||
*/
|
||||
|
||||
public function setRepeat(iter:int):void
|
||||
{
|
||||
|
||||
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.
|
||||
*/
|
||||
|
||||
public function setTransparent(c:Number):void
|
||||
{
|
||||
|
||||
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
|
||||
*/
|
||||
|
||||
public function addFrame(im:BitmapData):Boolean
|
||||
{
|
||||
|
||||
if ((im == null) || !started || out == null)
|
||||
|
||||
{
|
||||
throw new Error ("Please call start method before calling addFrame");
|
||||
return false;
|
||||
}
|
||||
|
||||
var ok:Boolean = true;
|
||||
|
||||
try {
|
||||
|
||||
image = new Bitmap ( im );
|
||||
if (!sizeSet) setSize(image.width, image.height);
|
||||
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.
|
||||
*/
|
||||
|
||||
public function finish():Boolean
|
||||
{
|
||||
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
|
||||
*/
|
||||
|
||||
private function reset ( ):void
|
||||
{
|
||||
|
||||
// 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
|
||||
* <code>setDelay(1000/fps)</code>.
|
||||
* @param fps
|
||||
* float frame rate (frames per second)
|
||||
*/
|
||||
|
||||
public function setFrameRate(fps:Number):void
|
||||
{
|
||||
|
||||
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
|
||||
*/
|
||||
|
||||
public function setQuality(quality:int):void
|
||||
{
|
||||
|
||||
if (quality < 1) quality = 1;
|
||||
sample = 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.
|
||||
*/
|
||||
|
||||
private function setSize(w:int, h:int):void
|
||||
{
|
||||
|
||||
if (started && !firstFrame) return;
|
||||
width = w;
|
||||
height = h;
|
||||
if (width < 1)width = 320;
|
||||
if (height < 1)height = 240;
|
||||
sizeSet = true
|
||||
|
||||
}
|
||||
|
||||
/**
|
||||
* Initiates GIF file creation on the given stream.
|
||||
* @param os
|
||||
* OutputStream on which GIF images are written.
|
||||
* @return false if initial write failed.
|
||||
*
|
||||
*/
|
||||
|
||||
public function start():Boolean
|
||||
{
|
||||
|
||||
reset();
|
||||
var ok:Boolean = true;
|
||||
closeStream = false;
|
||||
out = new ByteArray;
|
||||
try {
|
||||
out.writeUTFBytes("GIF89a"); // header
|
||||
} catch (e:Error) {
|
||||
ok = false;
|
||||
}
|
||||
|
||||
return started = ok;
|
||||
|
||||
}
|
||||
|
||||
/**
|
||||
* Analyzes image colors and creates color map.
|
||||
*/
|
||||
|
||||
private function analyzePixels():void
|
||||
{
|
||||
|
||||
var len:int = pixels.length;
|
||||
var nPix:int = len / 3;
|
||||
indexedPixels = new ByteArray;
|
||||
var nq:NeuQuant = new NeuQuant(pixels, len, sample);
|
||||
// initialize quantizer
|
||||
colorTab = nq.process(); // create reduced palette
|
||||
// map image pixels to new palette
|
||||
var k:int = 0;
|
||||
for (var j:int = 0; j < nPix; j++) {
|
||||
var index:int = 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
|
||||
*
|
||||
*/
|
||||
|
||||
private function findClosest(c:Number):int
|
||||
{
|
||||
|
||||
if (colorTab == null) return -1;
|
||||
var r:int = (c & 0xFF0000) >> 16;
|
||||
var g:int = (c & 0x00FF00) >> 8;
|
||||
var b:int = (c & 0x0000FF);
|
||||
var minpos:int = 0;
|
||||
var dmin:int = 256 * 256 * 256;
|
||||
var len:int = colorTab.length;
|
||||
|
||||
for (var i:int = 0; i < len;) {
|
||||
var dr:int = r - (colorTab[i++] & 0xff);
|
||||
var dg:int = g - (colorTab[i++] & 0xff);
|
||||
var db:int = b - (colorTab[i] & 0xff);
|
||||
var d:int = dr * dr + dg * dg + db * db;
|
||||
var index:int = i / 3;
|
||||
if (usedEntry[index] && (d < dmin)) {
|
||||
dmin = d;
|
||||
minpos = index;
|
||||
}
|
||||
i++;
|
||||
}
|
||||
return minpos;
|
||||
|
||||
}
|
||||
|
||||
/**
|
||||
* Extracts image pixels into byte array "pixels
|
||||
*/
|
||||
|
||||
private function getImagePixels():void
|
||||
{
|
||||
|
||||
var w:int = image.width;
|
||||
var h:int = image.height;
|
||||
pixels = new ByteArray;
|
||||
|
||||
var count:int = 0;
|
||||
|
||||
for ( var i:int = 0; i < h; i++ )
|
||||
{
|
||||
|
||||
for (var j:int = 0; j < w; j++ )
|
||||
{
|
||||
|
||||
var pixel:Number = image.bitmapData.getPixel( j, i );
|
||||
|
||||
pixels[count] = (pixel & 0xFF0000) >> 16;
|
||||
count++;
|
||||
pixels[count] = (pixel & 0x00FF00) >> 8;
|
||||
count++;
|
||||
pixels[count] = (pixel & 0x0000FF);
|
||||
count++;
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
/**
|
||||
* Writes Graphic Control Extension
|
||||
*/
|
||||
|
||||
private function writeGraphicCtrlExt():void
|
||||
{
|
||||
|
||||
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
|
||||
*/
|
||||
|
||||
private function writeImageDesc():void
|
||||
{
|
||||
|
||||
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
|
||||
*/
|
||||
|
||||
private function writeLSD():void
|
||||
{
|
||||
|
||||
// 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.
|
||||
*/
|
||||
|
||||
private function writeNetscapeExt():void
|
||||
{
|
||||
|
||||
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
|
||||
*/
|
||||
|
||||
private function writePalette():void
|
||||
{
|
||||
|
||||
out.writeBytes(colorTab, 0, colorTab.length);
|
||||
var n:int = (3 * 256) - colorTab.length;
|
||||
for (var i:int = 0; i < n; i++) out.writeByte(0);
|
||||
|
||||
}
|
||||
|
||||
private function WriteShort (pValue:int):void
|
||||
{
|
||||
|
||||
out.writeByte( pValue & 0xFF );
|
||||
out.writeByte( (pValue >> 8) & 0xFF);
|
||||
|
||||
}
|
||||
|
||||
/**
|
||||
* Encodes and writes pixel data
|
||||
*/
|
||||
|
||||
private function writePixels():void
|
||||
{
|
||||
|
||||
var myencoder:LZWEncoder = new LZWEncoder(width, height, indexedPixels, colorDepth);
|
||||
myencoder.encode(out);
|
||||
|
||||
}
|
||||
|
||||
/**
|
||||
* retrieves the GIF stream
|
||||
*/
|
||||
public function get stream ( ):ByteArray
|
||||
{
|
||||
|
||||
return out;
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,333 @@
|
||||
/**
|
||||
* This class handles LZW encoding
|
||||
* Adapted from Jef Poskanzer's Java port by way of J. M. G. Elliott.
|
||||
* @author Kevin Weiner (original Java version - kweiner@fmsware.com)
|
||||
* @author Thibault Imbert (AS3 version - bytearray.org)
|
||||
* @version 0.1 AS3 implementation
|
||||
*/
|
||||
|
||||
package org.bytearray.gif.encoder
|
||||
{
|
||||
import flash.utils.ByteArray;
|
||||
|
||||
public class LZWEncoder
|
||||
{
|
||||
private static var EOF:int = -1;
|
||||
private var imgW:int;
|
||||
private var imgH:int
|
||||
private var pixAry:ByteArray;
|
||||
private var initCodeSize:int;
|
||||
private var remaining:int;
|
||||
private var curPixel:int;
|
||||
|
||||
// GIFCOMPR.C - GIF Image compression routines
|
||||
// Lempel-Ziv compression based on 'compress'. GIF modifications by
|
||||
// David Rowley (mgardi@watdcsu.waterloo.edu)
|
||||
// General DEFINEs
|
||||
|
||||
private static var BITS:int = 12;
|
||||
private static var HSIZE:int = 5003; // 80% occupancy
|
||||
|
||||
// GIF Image compression - modified 'compress'
|
||||
// Based on: compress.c - File compression ala IEEE Computer, June 1984.
|
||||
// By Authors: Spencer W. Thomas (decvax!harpo!utah-cs!utah-gr!thomas)
|
||||
// Jim McKie (decvax!mcvax!jim)
|
||||
// Steve Davies (decvax!vax135!petsd!peora!srd)
|
||||
// Ken Turkowski (decvax!decwrl!turtlevax!ken)
|
||||
// James A. Woods (decvax!ihnp4!ames!jaw)
|
||||
// Joe Orost (decvax!vax135!petsd!joe)
|
||||
|
||||
private var n_bits:int // number of bits/code
|
||||
private var maxbits:int = BITS; // user settable max # bits/code
|
||||
private var maxcode:int // maximum code, given n_bits
|
||||
private var maxmaxcode:int = 1 << BITS; // should NEVER generate this code
|
||||
private var htab:Array = new Array;
|
||||
private var codetab:Array = new Array;
|
||||
private var hsize:int = HSIZE; // for dynamic table sizing
|
||||
private var free_ent:int = 0; // first unused entry
|
||||
|
||||
// block compression parameters -- after all codes are used up,
|
||||
// and compression rate changes, start over.
|
||||
|
||||
private var clear_flg:Boolean = false;
|
||||
|
||||
// Algorithm: use open addressing double hashing (no chaining) on the
|
||||
// prefix code / next character combination. We do a variant of Knuth's
|
||||
// algorithm D (vol. 3, sec. 6.4) along with G. Knott's relatively-prime
|
||||
// secondary probe. Here, the modular division first probe is gives way
|
||||
// to a faster exclusive-or manipulation. Also do block compression with
|
||||
// an adaptive reset, whereby the code table is cleared when the compression
|
||||
// ratio decreases, but after the table fills. The variable-length output
|
||||
// codes are re-sized at this point, and a special CLEAR code is generated
|
||||
// for the decompressor. Late addition: construct the table according to
|
||||
// file size for noticeable speed improvement on small files. Please direct
|
||||
// questions about this implementation to ames!jaw.
|
||||
|
||||
private var g_init_bits:int;
|
||||
private var ClearCode:int;
|
||||
private var EOFCode:int;
|
||||
|
||||
// output
|
||||
// Output the given code.
|
||||
// Inputs:
|
||||
// code: A n_bits-bit integer. If == -1, then EOF. This assumes
|
||||
// that n_bits =< wordsize - 1.
|
||||
// Outputs:
|
||||
// Outputs code to the file.
|
||||
// Assumptions:
|
||||
// Chars are 8 bits long.
|
||||
// Algorithm:
|
||||
// Maintain a BITS character long buffer (so that 8 codes will
|
||||
// fit in it exactly). Use the VAX insv instruction to insert each
|
||||
// code in turn. When the buffer fills up empty it and start over.
|
||||
|
||||
private var cur_accum:int = 0;
|
||||
private var cur_bits:int = 0;
|
||||
private var masks:Array = [ 0x0000, 0x0001, 0x0003, 0x0007, 0x000F, 0x001F, 0x003F, 0x007F, 0x00FF, 0x01FF, 0x03FF, 0x07FF, 0x0FFF, 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF ];
|
||||
|
||||
// Number of characters so far in this 'packet'
|
||||
private var a_count:int;
|
||||
|
||||
// Define the storage for the packet accumulator
|
||||
private var accum:ByteArray = new ByteArray;
|
||||
|
||||
public function LZWEncoder (width:int, height:int, pixels:ByteArray, color_depth:int)
|
||||
{
|
||||
|
||||
imgW = width;
|
||||
imgH = height;
|
||||
pixAry = pixels;
|
||||
initCodeSize = Math.max(2, color_depth);
|
||||
|
||||
}
|
||||
|
||||
// Add a character to the end of the current packet, and if it is 254
|
||||
// characters, flush the packet to disk.
|
||||
private function char_out(c:Number, outs:ByteArray):void
|
||||
{
|
||||
|
||||
accum[a_count++] = c;
|
||||
if (a_count >= 254)flush_char(outs);
|
||||
|
||||
}
|
||||
|
||||
// Clear out the hash table
|
||||
// table clear for block compress
|
||||
|
||||
private function cl_block(outs:ByteArray):void
|
||||
{
|
||||
|
||||
cl_hash(hsize);
|
||||
free_ent = ClearCode + 2;
|
||||
clear_flg = true;
|
||||
output(ClearCode, outs);
|
||||
|
||||
}
|
||||
|
||||
// reset code table
|
||||
private function cl_hash(hsize:int):void
|
||||
{
|
||||
|
||||
for (var i:int = 0; i < hsize; ++i) htab[i] = -1;
|
||||
|
||||
}
|
||||
|
||||
public function compress(init_bits:int, outs:ByteArray):void
|
||||
|
||||
{
|
||||
|
||||
var fcode:int;
|
||||
var i:int /* = 0 */;
|
||||
var c:int;
|
||||
var ent:int;
|
||||
var disp:int;
|
||||
var hsize_reg:int;
|
||||
var hshift:int;
|
||||
|
||||
// Set up the globals: g_init_bits - initial number of bits
|
||||
g_init_bits = init_bits;
|
||||
|
||||
// Set up the necessary values
|
||||
clear_flg = false;
|
||||
n_bits = g_init_bits;
|
||||
maxcode = MAXCODE(n_bits);
|
||||
|
||||
ClearCode = 1 << (init_bits - 1);
|
||||
EOFCode = ClearCode + 1;
|
||||
free_ent = ClearCode + 2;
|
||||
|
||||
a_count = 0; // clear packet
|
||||
|
||||
ent = nextPixel();
|
||||
|
||||
hshift = 0;
|
||||
for (fcode = hsize; fcode < 65536; fcode *= 2)
|
||||
++hshift;
|
||||
hshift = 8 - hshift; // set hash code range bound
|
||||
|
||||
hsize_reg = hsize;
|
||||
cl_hash(hsize_reg); // clear hash table
|
||||
|
||||
output(ClearCode, outs);
|
||||
|
||||
outer_loop: while ((c = nextPixel()) != EOF)
|
||||
|
||||
{
|
||||
|
||||
fcode = (c << maxbits) + ent;
|
||||
i = (c << hshift) ^ ent; // xor hashing
|
||||
|
||||
if (htab[i] == fcode)
|
||||
{
|
||||
ent = codetab[i];
|
||||
continue;
|
||||
} else if (htab[i] >= 0) // non-empty slot
|
||||
{
|
||||
disp = hsize_reg - i; // secondary hash (after G. Knott)
|
||||
if (i == 0)
|
||||
disp = 1;
|
||||
do
|
||||
{
|
||||
|
||||
if ((i -= disp) < 0) i += hsize_reg;
|
||||
|
||||
if (htab[i] == fcode)
|
||||
{
|
||||
ent = codetab[i];
|
||||
continue outer_loop;
|
||||
}
|
||||
} while (htab[i] >= 0);
|
||||
}
|
||||
|
||||
output(ent, outs);
|
||||
ent = c;
|
||||
if (free_ent < maxmaxcode)
|
||||
{
|
||||
codetab[i] = free_ent++; // code -> hashtable
|
||||
htab[i] = fcode;
|
||||
} else cl_block(outs);
|
||||
}
|
||||
|
||||
// Put out the final code.
|
||||
output(ent, outs);
|
||||
output(EOFCode, outs);
|
||||
|
||||
}
|
||||
|
||||
// ----------------------------------------------------------------------------
|
||||
public function encode(os:ByteArray):void
|
||||
{
|
||||
|
||||
os.writeByte(initCodeSize); // write "initial code size" byte
|
||||
remaining = imgW * imgH; // reset navigation variables
|
||||
curPixel = 0;
|
||||
compress(initCodeSize + 1, os); // compress and write the pixel data
|
||||
os.writeByte(0); // write block terminator
|
||||
|
||||
}
|
||||
|
||||
// Flush the packet to disk, and reset the accumulator
|
||||
private function flush_char(outs:ByteArray):void
|
||||
{
|
||||
|
||||
if (a_count > 0)
|
||||
{
|
||||
outs.writeByte(a_count);
|
||||
outs.writeBytes(accum, 0, a_count);
|
||||
a_count = 0;
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
private function MAXCODE(n_bits:int):int
|
||||
{
|
||||
|
||||
return (1 << n_bits) - 1;
|
||||
|
||||
}
|
||||
|
||||
// ----------------------------------------------------------------------------
|
||||
// Return the next pixel from the image
|
||||
// ----------------------------------------------------------------------------
|
||||
|
||||
private function nextPixel():int
|
||||
{
|
||||
|
||||
if (remaining == 0) return EOF;
|
||||
|
||||
--remaining;
|
||||
|
||||
var pix:Number = pixAry[curPixel++];
|
||||
|
||||
return pix & 0xff;
|
||||
|
||||
}
|
||||
|
||||
private function output(code:int, outs:ByteArray):void
|
||||
|
||||
{
|
||||
|
||||
cur_accum &= masks[cur_bits];
|
||||
|
||||
if (cur_bits > 0) cur_accum |= (code << cur_bits);
|
||||
else cur_accum = code;
|
||||
|
||||
cur_bits += n_bits;
|
||||
|
||||
while (cur_bits >= 8)
|
||||
|
||||
{
|
||||
|
||||
char_out((cur_accum & 0xff), outs);
|
||||
cur_accum >>= 8;
|
||||
cur_bits -= 8;
|
||||
|
||||
}
|
||||
|
||||
// If the next entry is going to be too big for the code size,
|
||||
// then increase it, if possible.
|
||||
|
||||
if (free_ent > maxcode || clear_flg)
|
||||
{
|
||||
|
||||
if (clear_flg)
|
||||
{
|
||||
|
||||
maxcode = MAXCODE(n_bits = g_init_bits);
|
||||
clear_flg = false;
|
||||
|
||||
} else
|
||||
{
|
||||
|
||||
++n_bits;
|
||||
|
||||
if (n_bits == maxbits) maxcode = maxmaxcode;
|
||||
|
||||
else maxcode = MAXCODE(n_bits);
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
if (code == EOFCode)
|
||||
{
|
||||
|
||||
// At EOF, write the rest of the buffer.
|
||||
while (cur_bits > 0)
|
||||
{
|
||||
|
||||
char_out((cur_accum & 0xff), outs);
|
||||
cur_accum >>= 8;
|
||||
cur_bits -= 8;
|
||||
}
|
||||
|
||||
|
||||
flush_char(outs);
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
@@ -0,0 +1,669 @@
|
||||
/*
|
||||
* NeuQuant Neural-Net Quantization Algorithm
|
||||
* ------------------------------------------
|
||||
*
|
||||
* Copyright (c) 1994 Anthony Dekker
|
||||
*
|
||||
* NEUQUANT Neural-Net quantization algorithm by Anthony Dekker, 1994. See
|
||||
* "Kohonen neural networks for optimal colour quantization" in "Network:
|
||||
* Computation in Neural Systems" Vol. 5 (1994) pp 351-367. for a discussion of
|
||||
* the algorithm.
|
||||
*
|
||||
* Any party obtaining a copy of these files from the author, directly or
|
||||
* indirectly, is granted, free of charge, a full and unrestricted irrevocable,
|
||||
* world-wide, paid up, royalty-free, nonexclusive right and license to deal in
|
||||
* this software and documentation files (the "Software"), including without
|
||||
* limitation the rights to use, copy, modify, merge, publish, distribute,
|
||||
* sublicense, and/or sell copies of the Software, and to permit persons who
|
||||
* receive copies from any such party to do so, with the only requirement being
|
||||
* that this copyright notice remain intact.
|
||||
*/
|
||||
|
||||
/*
|
||||
* This class handles Neural-Net quantization algorithm
|
||||
* @author Kevin Weiner (original Java version - kweiner@fmsware.com)
|
||||
* @author Thibault Imbert (AS3 version - bytearray.org)
|
||||
* @version 0.1 AS3 implementation
|
||||
*/
|
||||
|
||||
package org.bytearray.gif.encoder
|
||||
{
|
||||
import flash.utils.ByteArray;
|
||||
|
||||
public class NeuQuant
|
||||
{
|
||||
private static var netsize:int = 256; /* number of colours used */
|
||||
|
||||
/* four primes near 500 - assume no image has a length so large */
|
||||
/* that it is divisible by all four primes */
|
||||
|
||||
private static var prime1:int = 499;
|
||||
private static var prime2:int = 491;
|
||||
private static var prime3:int = 487;
|
||||
private static var prime4:int = 503;
|
||||
private static var minpicturebytes:int = (3 * prime4);
|
||||
|
||||
/* minimum size for input image */
|
||||
/*
|
||||
* Program Skeleton ---------------- [select samplefac in range 1..30] [read
|
||||
* image from input file] pic = (unsigned char*) malloc(3*width*height);
|
||||
* initnet(pic,3*width*height,samplefac); learn(); unbiasnet(); [write output
|
||||
* image header, using writecolourmap(f)] inxbuild(); write output image using
|
||||
* inxsearch(b,g,r)
|
||||
*/
|
||||
|
||||
/*
|
||||
* Network Definitions -------------------
|
||||
*/
|
||||
|
||||
private static var maxnetpos:int = (netsize - 1);
|
||||
private static var netbiasshift:int = 4; /* bias for colour values */
|
||||
private static var ncycles:int = 100; /* no. of learning cycles */
|
||||
|
||||
/* defs for freq and bias */
|
||||
private static var intbiasshift:int = 16; /* bias for fractions */
|
||||
private static var intbias:int = (1 << intbiasshift);
|
||||
private static var gammashift:int = 10; /* gamma = 1024 */
|
||||
private static var gamma:int = (1 << gammashift);
|
||||
private static var betashift:int = 10;
|
||||
private static var beta:int = (intbias >> betashift); /* beta = 1/1024 */
|
||||
private static var betagamma:int = (intbias << (gammashift - betashift));
|
||||
|
||||
/* defs for decreasing radius factor */
|
||||
private static var initrad:int = (netsize >> 3); /*
|
||||
* for 256 cols, radius
|
||||
* starts
|
||||
*/
|
||||
|
||||
private static var radiusbiasshift:int = 6; /* at 32.0 biased by 6 bits */
|
||||
private static var radiusbias:int = (1 << radiusbiasshift);
|
||||
private static var initradius:int = (initrad * radiusbias); /*
|
||||
* and
|
||||
* decreases
|
||||
* by a
|
||||
*/
|
||||
|
||||
private static var radiusdec:int = 30; /* factor of 1/30 each cycle */
|
||||
|
||||
/* defs for decreasing alpha factor */
|
||||
private static var alphabiasshift:int = 10; /* alpha starts at 1.0 */
|
||||
private static var initalpha:int = (1 << alphabiasshift);
|
||||
private var alphadec:int /* biased by 10 bits */
|
||||
|
||||
/* radbias and alpharadbias used for radpower calculation */
|
||||
private static var radbiasshift:int = 8;
|
||||
private static var radbias:int = (1 << radbiasshift);
|
||||
private static var alpharadbshift:int = (alphabiasshift + radbiasshift);
|
||||
|
||||
private static var alpharadbias:int = (1 << alpharadbshift);
|
||||
|
||||
/*
|
||||
* Types and Global Variables --------------------------
|
||||
*/
|
||||
|
||||
private var thepicture:ByteArray/* the input image itself */
|
||||
private var lengthcount:int; /* lengthcount = H*W*3 */
|
||||
private var samplefac:int; /* sampling factor 1..30 */
|
||||
|
||||
// typedef int pixel[4]; /* BGRc */
|
||||
private var network:Array; /* the network itself - [netsize][4] */
|
||||
protected var netindex:Array = new Array();
|
||||
|
||||
/* for network lookup - really 256 */
|
||||
private var bias:Array = new Array();
|
||||
|
||||
/* bias and freq arrays for learning */
|
||||
private var freq:Array = new Array();
|
||||
private var radpower:Array = new Array();
|
||||
|
||||
public function NeuQuant(thepic:ByteArray, len:int, sample:int)
|
||||
{
|
||||
|
||||
var i:int;
|
||||
var p:Array;
|
||||
|
||||
thepicture = thepic;
|
||||
lengthcount = len;
|
||||
samplefac = sample;
|
||||
|
||||
network = new Array(netsize);
|
||||
|
||||
for (i = 0; i < netsize; i++)
|
||||
{
|
||||
|
||||
network[i] = new Array(4);
|
||||
p = network[i];
|
||||
p[0] = p[1] = p[2] = (i << (netbiasshift + 8)) / netsize;
|
||||
freq[i] = intbias / netsize; /* 1/netsize */
|
||||
bias[i] = 0;
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
private function colorMap():ByteArray
|
||||
{
|
||||
|
||||
var map:ByteArray = new ByteArray;
|
||||
var index:Array = new Array(netsize);
|
||||
for (var i:int = 0; i < netsize; i++)
|
||||
index[network[i][3]] = i;
|
||||
var k:int = 0;
|
||||
for (var l:int = 0; l < netsize; l++) {
|
||||
var j:int = index[l];
|
||||
map[k++] = (network[j][0]);
|
||||
map[k++] = (network[j][1]);
|
||||
map[k++] = (network[j][2]);
|
||||
}
|
||||
return map;
|
||||
|
||||
}
|
||||
|
||||
/*
|
||||
* Insertion sort of network and building of netindex[0..255] (to do after
|
||||
* unbias)
|
||||
* -------------------------------------------------------------------------------
|
||||
*/
|
||||
|
||||
private function inxbuild():void
|
||||
{
|
||||
|
||||
var i:int;
|
||||
var j:int;
|
||||
var smallpos:int;
|
||||
var smallval:int;
|
||||
var p:Array;
|
||||
var q:Array;
|
||||
var previouscol:int
|
||||
var startpos:int
|
||||
|
||||
previouscol = 0;
|
||||
startpos = 0;
|
||||
for (i = 0; i < netsize; i++)
|
||||
{
|
||||
|
||||
p = network[i];
|
||||
smallpos = i;
|
||||
smallval = p[1]; /* index on g */
|
||||
/* find smallest in i..netsize-1 */
|
||||
for (j = i + 1; j < netsize; j++)
|
||||
{
|
||||
q = network[j];
|
||||
if (q[1] < smallval)
|
||||
{ /* index on g */
|
||||
|
||||
smallpos = j;
|
||||
smallval = q[1]; /* index on g */
|
||||
}
|
||||
}
|
||||
|
||||
q = network[smallpos];
|
||||
/* swap p (i) and q (smallpos) entries */
|
||||
|
||||
if (i != smallpos)
|
||||
{
|
||||
|
||||
j = q[0];
|
||||
q[0] = p[0];
|
||||
p[0] = j;
|
||||
j = q[1];
|
||||
q[1] = p[1];
|
||||
p[1] = j;
|
||||
j = q[2];
|
||||
q[2] = p[2];
|
||||
p[2] = j;
|
||||
j = q[3];
|
||||
q[3] = p[3];
|
||||
p[3] = j;
|
||||
|
||||
}
|
||||
|
||||
/* smallval entry is now in position i */
|
||||
|
||||
if (smallval != previouscol)
|
||||
|
||||
{
|
||||
|
||||
netindex[previouscol] = (startpos + i) >> 1;
|
||||
|
||||
for (j = previouscol + 1; j < smallval; j++) netindex[j] = i;
|
||||
|
||||
previouscol = smallval;
|
||||
startpos = i;
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
netindex[previouscol] = (startpos + maxnetpos) >> 1;
|
||||
for (j = previouscol + 1; j < 256; j++) netindex[j] = maxnetpos; /* really 256 */
|
||||
|
||||
}
|
||||
|
||||
/*
|
||||
* Main Learning Loop ------------------
|
||||
*/
|
||||
|
||||
private function learn():void
|
||||
|
||||
{
|
||||
|
||||
var i:int;
|
||||
var j:int;
|
||||
var b:int;
|
||||
var g:int
|
||||
var r:int;
|
||||
var radius:int;
|
||||
var rad:int;
|
||||
var alpha:int;
|
||||
var step:int;
|
||||
var delta:int;
|
||||
var samplepixels:int;
|
||||
var p:ByteArray;
|
||||
var pix:int;
|
||||
var lim:int;
|
||||
|
||||
if (lengthcount < minpicturebytes) samplefac = 1;
|
||||
|
||||
alphadec = 30 + ((samplefac - 1) / 3);
|
||||
p = thepicture;
|
||||
pix = 0;
|
||||
lim = lengthcount;
|
||||
samplepixels = lengthcount / (3 * samplefac);
|
||||
delta = samplepixels / ncycles;
|
||||
alpha = initalpha;
|
||||
radius = initradius;
|
||||
|
||||
rad = radius >> radiusbiasshift;
|
||||
if (rad <= 1) rad = 0;
|
||||
|
||||
for (i = 0; i < rad; i++) radpower[i] = alpha * (((rad * rad - i * i) * radbias) / (rad * rad));
|
||||
|
||||
|
||||
if (lengthcount < minpicturebytes) step = 3;
|
||||
|
||||
else if ((lengthcount % prime1) != 0) step = 3 * prime1;
|
||||
|
||||
else
|
||||
|
||||
{
|
||||
|
||||
if ((lengthcount % prime2) != 0) step = 3 * prime2;
|
||||
|
||||
else
|
||||
|
||||
{
|
||||
|
||||
if ((lengthcount % prime3) != 0) step = 3 * prime3;
|
||||
|
||||
else step = 3 * prime4;
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
i = 0;
|
||||
|
||||
while (i < samplepixels)
|
||||
|
||||
{
|
||||
|
||||
b = (p[pix + 0] & 0xff) << netbiasshift;
|
||||
g = (p[pix + 1] & 0xff) << netbiasshift;
|
||||
r = (p[pix + 2] & 0xff) << netbiasshift;
|
||||
j = contest(b, g, r);
|
||||
|
||||
altersingle(alpha, j, b, g, r);
|
||||
|
||||
if (rad != 0) alterneigh(rad, j, b, g, r); /* alter neighbours */
|
||||
|
||||
pix += step;
|
||||
|
||||
if (pix >= lim) pix -= lengthcount;
|
||||
|
||||
i++;
|
||||
|
||||
if (delta == 0) delta = 1;
|
||||
|
||||
if (i % delta == 0)
|
||||
|
||||
{
|
||||
|
||||
alpha -= alpha / alphadec;
|
||||
radius -= radius / radiusdec;
|
||||
rad = radius >> radiusbiasshift;
|
||||
|
||||
if (rad <= 1) rad = 0;
|
||||
|
||||
for (j = 0; j < rad; j++) radpower[j] = alpha * (((rad * rad - j * j) * radbias) / (rad * rad));
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
/*
|
||||
** Search for BGR values 0..255 (after net is unbiased) and return colour
|
||||
* index
|
||||
* ----------------------------------------------------------------------------
|
||||
*/
|
||||
|
||||
public function map(b:int, g:int, r:int):int
|
||||
|
||||
{
|
||||
|
||||
var i:int;
|
||||
var j:int;
|
||||
var dist:int
|
||||
var a:int;
|
||||
var bestd:int;
|
||||
var p:Array;
|
||||
var best:int;
|
||||
|
||||
bestd = 1000; /* biggest possible dist is 256*3 */
|
||||
best = -1;
|
||||
i = netindex[g]; /* index on g */
|
||||
j = i - 1; /* start at netindex[g] and work outwards */
|
||||
|
||||
while ((i < netsize) || (j >= 0))
|
||||
|
||||
{
|
||||
|
||||
if (i < netsize)
|
||||
|
||||
{
|
||||
|
||||
p = network[i];
|
||||
|
||||
dist = p[1] - g; /* inx key */
|
||||
|
||||
if (dist >= bestd) i = netsize; /* stop iter */
|
||||
|
||||
else
|
||||
|
||||
{
|
||||
|
||||
i++;
|
||||
|
||||
if (dist < 0) dist = -dist;
|
||||
|
||||
a = p[0] - b;
|
||||
|
||||
if (a < 0) a = -a;
|
||||
|
||||
dist += a;
|
||||
|
||||
if (dist < bestd)
|
||||
|
||||
{
|
||||
|
||||
a = p[2] - r;
|
||||
|
||||
if (a < 0) a = -a;
|
||||
|
||||
dist += a;
|
||||
|
||||
if (dist < bestd)
|
||||
|
||||
{
|
||||
|
||||
bestd = dist;
|
||||
best = p[3];
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
if (j >= 0)
|
||||
{
|
||||
|
||||
p = network[j];
|
||||
|
||||
dist = g - p[1]; /* inx key - reverse dif */
|
||||
|
||||
if (dist >= bestd) j = -1; /* stop iter */
|
||||
|
||||
else
|
||||
{
|
||||
|
||||
j--;
|
||||
if (dist < 0) dist = -dist;
|
||||
a = p[0] - b;
|
||||
if (a < 0) a = -a;
|
||||
dist += a;
|
||||
|
||||
if (dist < bestd)
|
||||
|
||||
{
|
||||
|
||||
a = p[2] - r;
|
||||
if (a < 0)a = -a;
|
||||
dist += a;
|
||||
if (dist < bestd)
|
||||
{
|
||||
bestd = dist;
|
||||
best = p[3];
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
return (best);
|
||||
|
||||
}
|
||||
|
||||
public function process():ByteArray
|
||||
{
|
||||
|
||||
learn();
|
||||
unbiasnet();
|
||||
inxbuild();
|
||||
return colorMap();
|
||||
|
||||
}
|
||||
|
||||
/*
|
||||
* Unbias network to give byte values 0..255 and record position i to prepare
|
||||
* for sort
|
||||
* -----------------------------------------------------------------------------------
|
||||
*/
|
||||
|
||||
private function unbiasnet():void
|
||||
|
||||
{
|
||||
|
||||
var i:int;
|
||||
var j:int;
|
||||
|
||||
for (i = 0; i < netsize; i++)
|
||||
{
|
||||
network[i][0] >>= netbiasshift;
|
||||
network[i][1] >>= netbiasshift;
|
||||
network[i][2] >>= netbiasshift;
|
||||
network[i][3] = i; /* record colour no */
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
/*
|
||||
* Move adjacent neurons by precomputed alpha*(1-((i-j)^2/[r]^2)) in
|
||||
* radpower[|i-j|]
|
||||
* ---------------------------------------------------------------------------------
|
||||
*/
|
||||
|
||||
private function alterneigh(rad:int, i:int, b:int, g:int, r:int):void
|
||||
|
||||
{
|
||||
|
||||
var j:int;
|
||||
var k:int;
|
||||
var lo:int;
|
||||
var hi:int;
|
||||
var a:int;
|
||||
var m:int;
|
||||
|
||||
var p:Array;
|
||||
|
||||
lo = i - rad;
|
||||
if (lo < -1) lo = -1;
|
||||
|
||||
hi = i + rad;
|
||||
|
||||
if (hi > netsize) hi = netsize;
|
||||
|
||||
j = i + 1;
|
||||
k = i - 1;
|
||||
m = 1;
|
||||
|
||||
while ((j < hi) || (k > lo))
|
||||
|
||||
{
|
||||
|
||||
a = radpower[m++];
|
||||
|
||||
if (j < hi)
|
||||
|
||||
{
|
||||
|
||||
p = network[j++];
|
||||
|
||||
try {
|
||||
|
||||
p[0] -= (a * (p[0] - b)) / alpharadbias;
|
||||
p[1] -= (a * (p[1] - g)) / alpharadbias;
|
||||
p[2] -= (a * (p[2] - r)) / alpharadbias;
|
||||
|
||||
} catch (e:Error) {} // prevents 1.3 miscompilation
|
||||
|
||||
}
|
||||
|
||||
if (k > lo)
|
||||
|
||||
{
|
||||
|
||||
p = network[k--];
|
||||
|
||||
try
|
||||
{
|
||||
|
||||
p[0] -= (a * (p[0] - b)) / alpharadbias;
|
||||
p[1] -= (a * (p[1] - g)) / alpharadbias;
|
||||
p[2] -= (a * (p[2] - r)) / alpharadbias;
|
||||
|
||||
} catch (e:Error) {}
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
/*
|
||||
* Move neuron i towards biased (b,g,r) by factor alpha
|
||||
* ----------------------------------------------------
|
||||
*/
|
||||
|
||||
private function altersingle(alpha:int, i:int, b:int, g:int, r:int):void
|
||||
{
|
||||
|
||||
/* alter hit neuron */
|
||||
var n:Array = network[i];
|
||||
n[0] -= (alpha * (n[0] - b)) / initalpha;
|
||||
n[1] -= (alpha * (n[1] - g)) / initalpha;
|
||||
n[2] -= (alpha * (n[2] - r)) / initalpha;
|
||||
|
||||
}
|
||||
|
||||
/*
|
||||
* Search for biased BGR values ----------------------------
|
||||
*/
|
||||
|
||||
private function contest(b:int, g:int, r:int):int
|
||||
{
|
||||
|
||||
/* finds closest neuron (min dist) and updates freq */
|
||||
/* finds best neuron (min dist-bias) and returns position */
|
||||
/* for frequently chosen neurons, freq[i] is high and bias[i] is negative */
|
||||
/* bias[i] = gamma*((1/netsize)-freq[i]) */
|
||||
|
||||
var i:int;
|
||||
var dist:int;
|
||||
var a:int;
|
||||
var biasdist:int;
|
||||
var betafreq:int;
|
||||
var bestpos:int;
|
||||
var bestbiaspos:int;
|
||||
var bestd:int;
|
||||
var bestbiasd:int;
|
||||
var n:Array;
|
||||
|
||||
bestd = ~(1 << 31);
|
||||
bestbiasd = bestd;
|
||||
bestpos = -1;
|
||||
bestbiaspos = bestpos;
|
||||
|
||||
for (i = 0; i < netsize; i++)
|
||||
|
||||
{
|
||||
|
||||
n = network[i];
|
||||
dist = n[0] - b;
|
||||
|
||||
if (dist < 0) dist = -dist;
|
||||
|
||||
a = n[1] - g;
|
||||
|
||||
if (a < 0) a = -a;
|
||||
|
||||
dist += a;
|
||||
|
||||
a = n[2] - r;
|
||||
|
||||
if (a < 0) a = -a;
|
||||
|
||||
dist += a;
|
||||
|
||||
if (dist < bestd)
|
||||
|
||||
{
|
||||
|
||||
bestd = dist;
|
||||
bestpos = i;
|
||||
|
||||
}
|
||||
|
||||
biasdist = dist - ((bias[i]) >> (intbiasshift - netbiasshift));
|
||||
|
||||
if (biasdist < bestbiasd)
|
||||
|
||||
{
|
||||
|
||||
bestbiasd = biasdist;
|
||||
bestbiaspos = i;
|
||||
|
||||
}
|
||||
|
||||
betafreq = (freq[i] >> betashift);
|
||||
freq[i] -= betafreq;
|
||||
bias[i] += (betafreq << gammashift);
|
||||
|
||||
}
|
||||
|
||||
freq[bestpos] += beta;
|
||||
bias[bestpos] -= betagamma;
|
||||
return (bestbiaspos);
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
@@ -0,0 +1,10 @@
|
||||
package org.bytearray.gif.errors
|
||||
{
|
||||
public class FileTypeError extends Error
|
||||
{
|
||||
public function FileTypeError ( pMessage:String )
|
||||
{
|
||||
super ( pMessage );
|
||||
}
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,14 @@
|
||||
package org.bytearray.gif.events
|
||||
{
|
||||
import flash.events.Event;
|
||||
|
||||
public class FileTypeEvent extends Event
|
||||
{
|
||||
public static const INVALID:String = "invalid";
|
||||
|
||||
public function FileTypeEvent ( pType:String )
|
||||
{
|
||||
super ( pType, false, false );
|
||||
}
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,19 @@
|
||||
package org.bytearray.gif.events
|
||||
{
|
||||
import flash.events.Event;
|
||||
import org.bytearray.gif.frames.GIFFrame;
|
||||
|
||||
public class FrameEvent extends Event
|
||||
{
|
||||
public var frame:GIFFrame;
|
||||
|
||||
public static const FRAME_RENDERED:String = "rendered";
|
||||
|
||||
public function FrameEvent ( pType:String, pFrame:GIFFrame )
|
||||
{
|
||||
super ( pType, false, false );
|
||||
|
||||
frame = pFrame;
|
||||
}
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,18 @@
|
||||
package org.bytearray.gif.events
|
||||
{
|
||||
import flash.events.Event;
|
||||
import flash.geom.Rectangle;
|
||||
|
||||
public class GIFPlayerEvent extends Event
|
||||
{
|
||||
public var rect:Rectangle;
|
||||
|
||||
public static const COMPLETE:String = "complete";
|
||||
|
||||
public function GIFPlayerEvent ( pType:String, pRect:Rectangle )
|
||||
{
|
||||
super ( pType, false, false );
|
||||
rect = pRect;
|
||||
}
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,14 @@
|
||||
package org.bytearray.gif.events
|
||||
{
|
||||
import flash.events.Event;;
|
||||
|
||||
public class TimeoutEvent extends Event
|
||||
{
|
||||
public static const TIME_OUT:String = "timeout";
|
||||
|
||||
public function TimeoutEvent ( pType:String )
|
||||
{
|
||||
super ( pType, false, false );
|
||||
}
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,16 @@
|
||||
package org.bytearray.gif.frames
|
||||
{
|
||||
import flash.display.BitmapData;
|
||||
|
||||
public class GIFFrame
|
||||
{
|
||||
public var bitmapData:BitmapData;
|
||||
public var delay:int;
|
||||
|
||||
public function GIFFrame( pImage:BitmapData, pDelay:int )
|
||||
{
|
||||
bitmapData = pImage;
|
||||
delay = pDelay;
|
||||
}
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,339 @@
|
||||
/**
|
||||
* This class lets you play animated GIF files in AS3
|
||||
* @author Thibault Imbert (bytearray.org)
|
||||
* @version 0.6
|
||||
*/
|
||||
|
||||
package org.bytearray.gif.player
|
||||
{
|
||||
import flash.events.TimerEvent;
|
||||
import flash.net.URLLoaderDataFormat;
|
||||
import flash.net.URLLoader;
|
||||
import flash.net.URLRequest;
|
||||
import flash.events.Event;
|
||||
import flash.system.LoaderContext;
|
||||
import flash.utils.ByteArray;
|
||||
import flash.utils.Timer;
|
||||
import flash.display.Bitmap;
|
||||
import flash.display.BitmapData;
|
||||
import flash.utils.getTimer;
|
||||
import flash.events.IOErrorEvent;
|
||||
import flash.errors.ScriptTimeoutError;
|
||||
import org.bytearray.gif.frames.GIFFrame;
|
||||
import org.bytearray.gif.decoder.GIFDecoder;
|
||||
import org.bytearray.gif.events.GIFPlayerEvent;
|
||||
import org.bytearray.gif.events.FrameEvent;
|
||||
import org.bytearray.gif.events.TimeoutEvent;
|
||||
import org.bytearray.gif.events.FileTypeEvent;
|
||||
import org.bytearray.gif.errors.FileTypeError;
|
||||
|
||||
public class GIFPlayer extends Bitmap
|
||||
{
|
||||
private var urlLoader:URLLoader;
|
||||
private var gifDecoder:GIFDecoder
|
||||
private var aFrames:Array;
|
||||
private var myTimer:Timer;
|
||||
private var iInc:int;
|
||||
private var iIndex:int;
|
||||
private var auto:Boolean;
|
||||
private var arrayLng:uint;
|
||||
|
||||
public function GIFPlayer ( pAutoPlay:Boolean = true )
|
||||
{
|
||||
auto = pAutoPlay;
|
||||
iIndex = iInc = 0;
|
||||
|
||||
myTimer = new Timer ( 0, 0 );
|
||||
aFrames = new Array();
|
||||
urlLoader = new URLLoader();
|
||||
urlLoader.dataFormat = URLLoaderDataFormat.BINARY;
|
||||
|
||||
urlLoader.addEventListener ( Event.COMPLETE, onComplete );
|
||||
urlLoader.addEventListener ( IOErrorEvent.IO_ERROR, onIOError );
|
||||
|
||||
myTimer.addEventListener ( TimerEvent.TIMER, update );
|
||||
|
||||
gifDecoder = new GIFDecoder();
|
||||
}
|
||||
|
||||
private function onIOError ( pEvt:IOErrorEvent ):void
|
||||
{
|
||||
dispatchEvent ( pEvt );
|
||||
}
|
||||
|
||||
private function onComplete ( pEvt:Event ):void
|
||||
{
|
||||
readStream ( pEvt.target.data );
|
||||
}
|
||||
|
||||
private function readStream ( pBytes:ByteArray ):void
|
||||
{
|
||||
var gifStream:ByteArray = pBytes;
|
||||
|
||||
aFrames = new Array;
|
||||
iInc = 0;
|
||||
|
||||
try
|
||||
{
|
||||
gifDecoder.read ( gifStream );
|
||||
|
||||
var lng:int = gifDecoder.getFrameCount();
|
||||
|
||||
for ( var i:int = 0; i< lng; i++ )
|
||||
aFrames[int(i)] = gifDecoder.getFrame(i);
|
||||
|
||||
arrayLng = aFrames.length;
|
||||
|
||||
auto ? play() : gotoAndStop (1);
|
||||
|
||||
dispatchEvent ( new GIFPlayerEvent ( GIFPlayerEvent.COMPLETE , aFrames[0].bitmapData.rect ) );
|
||||
|
||||
} catch ( e:ScriptTimeoutError )
|
||||
{
|
||||
dispatchEvent ( new TimeoutEvent ( TimeoutEvent.TIME_OUT ) );
|
||||
|
||||
} catch ( e:FileTypeError )
|
||||
{
|
||||
dispatchEvent ( new FileTypeEvent ( FileTypeEvent.INVALID ) );
|
||||
|
||||
} catch ( e:Error )
|
||||
{
|
||||
throw new Error ("An unknown error occured, make sure the GIF file contains at least one frame\nNumber of frames : " + aFrames.length);
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
private function update ( pEvt:TimerEvent ) :void
|
||||
{
|
||||
var delay:int = aFrames[ int(iIndex = iInc++ % arrayLng) ].delay;
|
||||
|
||||
pEvt.target.delay = ( delay > 0 ) ? delay : 100;
|
||||
|
||||
switch ( gifDecoder.disposeValue )
|
||||
{
|
||||
case 1:
|
||||
if ( !iIndex )
|
||||
bitmapData = aFrames[ 0 ].bitmapData.clone();
|
||||
bitmapData.draw ( aFrames[ iIndex ].bitmapData );
|
||||
break
|
||||
case 2:
|
||||
bitmapData = aFrames[ iIndex ].bitmapData;
|
||||
break;
|
||||
}
|
||||
|
||||
dispatchEvent ( new FrameEvent ( FrameEvent.FRAME_RENDERED, aFrames[ iIndex ] ) );
|
||||
}
|
||||
|
||||
private function concat ( pIndex:int ):int
|
||||
{
|
||||
bitmapData.lock();
|
||||
for (var i:int = 0; i< pIndex; i++ )
|
||||
bitmapData.draw ( aFrames[ i ].bitmapData );
|
||||
bitmapData.unlock();
|
||||
|
||||
return i;
|
||||
}
|
||||
|
||||
/**
|
||||
* Load any GIF file
|
||||
*
|
||||
* @return void
|
||||
*/
|
||||
public function load ( pRequest:URLRequest ):void
|
||||
{
|
||||
stop();
|
||||
urlLoader.load ( pRequest );
|
||||
}
|
||||
|
||||
/**
|
||||
* Load any valid GIF ByteArray
|
||||
*
|
||||
* @return void
|
||||
*/
|
||||
public function loadBytes ( pBytes:ByteArray ):void
|
||||
{
|
||||
readStream ( pBytes );
|
||||
}
|
||||
|
||||
/**
|
||||
* Start playing
|
||||
*
|
||||
* @return void
|
||||
*/
|
||||
public function play ():void
|
||||
{
|
||||
if ( aFrames.length > 0 )
|
||||
{
|
||||
if ( !myTimer.running )
|
||||
myTimer.start();
|
||||
|
||||
} else throw new Error ("Nothing to play");
|
||||
}
|
||||
|
||||
/**
|
||||
* Stop playing
|
||||
*
|
||||
* @return void
|
||||
*/
|
||||
public function stop ():void
|
||||
{
|
||||
if ( myTimer.running )
|
||||
myTimer.stop();
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns current frame being played
|
||||
*
|
||||
* @return frame number
|
||||
*/
|
||||
public function get currentFrame ():int
|
||||
{
|
||||
return iIndex+1;
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns GIF's total frames
|
||||
*
|
||||
* @return number of frames
|
||||
*/
|
||||
public function get totalFrames ():int
|
||||
{
|
||||
return aFrames.length;
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns how many times the GIF file is played
|
||||
* A loop value of 0 means repeat indefinitiely.
|
||||
*
|
||||
* @return loop value
|
||||
*/
|
||||
public function get loopCount ():int
|
||||
{
|
||||
return gifDecoder.getLoopCount();
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns is the autoPlay value
|
||||
*
|
||||
* @return autoPlay value
|
||||
*/
|
||||
public function get autoPlay ():Boolean
|
||||
{
|
||||
return auto;
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns an array of GIFFrame objects
|
||||
*
|
||||
* @return aFrames
|
||||
*/
|
||||
public function get frames ():Array
|
||||
{
|
||||
return aFrames;
|
||||
}
|
||||
|
||||
/**
|
||||
* Moves the playhead to the specified frame and stops playing
|
||||
*
|
||||
* @return void
|
||||
*/
|
||||
public function gotoAndStop (pFrame:int):void
|
||||
{
|
||||
if ( pFrame >= 1 && pFrame <= aFrames.length )
|
||||
{
|
||||
if ( pFrame == currentFrame ) return;
|
||||
iIndex = iInc = int(int(pFrame)-1);
|
||||
|
||||
switch ( gifDecoder.disposeValue )
|
||||
{
|
||||
case 1:
|
||||
bitmapData = aFrames[ 0 ].bitmapData.clone();
|
||||
bitmapData.draw ( aFrames[ concat ( iInc ) ].bitmapData );
|
||||
break
|
||||
case 2:
|
||||
bitmapData = aFrames[ iInc ].bitmapData;
|
||||
break;
|
||||
}
|
||||
|
||||
if ( myTimer.running )
|
||||
myTimer.stop();
|
||||
|
||||
} else throw new RangeError ("Frame out of range, please specify a frame between 1 and " + aFrames.length );
|
||||
}
|
||||
|
||||
/**
|
||||
* Starts playing the GIF at the frame specified as parameter
|
||||
*
|
||||
* @return void
|
||||
*/
|
||||
public function gotoAndPlay (pFrame:int):void
|
||||
{
|
||||
if ( pFrame >= 1 && pFrame <= aFrames.length )
|
||||
{
|
||||
if ( pFrame == currentFrame ) return;
|
||||
iIndex = iInc = int(int(pFrame)-1);
|
||||
|
||||
switch ( gifDecoder.disposeValue )
|
||||
{
|
||||
case 1:
|
||||
bitmapData = aFrames[ 0 ].bitmapData.clone();
|
||||
bitmapData.draw ( aFrames[ concat ( iInc ) ].bitmapData );
|
||||
break
|
||||
case 2:
|
||||
bitmapData = aFrames[ iInc ].bitmapData;
|
||||
break;
|
||||
}
|
||||
if ( !myTimer.running ) myTimer.start();
|
||||
|
||||
} else throw new RangeError ("Frame out of range, please specify a frame between 1 and " + aFrames.length );
|
||||
}
|
||||
|
||||
/**
|
||||
* Retrieves a frame from the GIF file as a BitmapData
|
||||
*
|
||||
* @return BitmapData object
|
||||
*/
|
||||
public function getFrame ( pFrame:int ):GIFFrame
|
||||
{
|
||||
var frame:GIFFrame;
|
||||
|
||||
if ( pFrame >= 1 && pFrame <= aFrames.length )
|
||||
frame = aFrames[ pFrame-1 ];
|
||||
|
||||
else throw new RangeError ("Frame out of range, please specify a frame between 1 and " + aFrames.length );
|
||||
|
||||
return frame;
|
||||
}
|
||||
|
||||
/**
|
||||
* Retrieves the delay for a specific frame
|
||||
*
|
||||
* @return int
|
||||
*/
|
||||
public function getDelay ( pFrame:int ):int
|
||||
{
|
||||
var delay:int;
|
||||
|
||||
if ( pFrame >= 1 && pFrame <= aFrames.length )
|
||||
delay = aFrames[ pFrame-1 ].delay;
|
||||
|
||||
else throw new RangeError ("Frame out of range, please specify a frame between 1 and " + aFrames.length );
|
||||
|
||||
return delay;
|
||||
}
|
||||
|
||||
/**
|
||||
* Dispose a GIFPlayer instance
|
||||
*
|
||||
* @return int
|
||||
*/
|
||||
public function dispose():void
|
||||
{
|
||||
stop();
|
||||
var lng:int = aFrames.length;
|
||||
|
||||
for ( var i:int = 0; i< lng; i++ )
|
||||
aFrames[int(i)].bitmapData.dispose();
|
||||
}
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user