小程序源码 GifView.rar

package com.ant.liao; import java.io.ByteArrayInputStream; import java.io.InputStream; import android.graphics.Bitmap; import android.graphics.Bitmap.Config; import android.util.Log; public class GifDecoder extends Thread{ /**状态：正在解码中*/ public static final int STATUS_PARSING = 0; /**状态：图片格式错误*/ public static final int STATUS_FORMAT_ERROR = 1; /**状态：打开失败*/ public static final int STATUS_OPEN_ERROR = 2; /**状态：解码成功*/ public static final int STATUS_FINISH = -1; private InputStream in; private int status; public int width; // full image width public int height; // full image height private boolean gctFlag; // global color table used private int gctSize; // size of global color table private int loopCount = 1; // iterations; 0 = repeat forever private int[] gct; // global color table private int[] lct; // local color table private int[] act; // active color table private int bgIndex; // background color index private int bgColor; // background color private int lastBgColor; // previous bg color private int pixelAspect; // pixel aspect ratio private boolean lctFlag; // local color table flag private boolean interlace; // interlace flag private int lctSize; // local color table size private int ix, iy, iw, ih; // current image rectangle private int lrx, lry, lrw, lrh; private Bitmap image; // current frame private Bitmap lastImage; // previous frame private GifFrame currentFrame = null; private boolean isShow = false; private byte[] block = new byte[256]; // current data block private int blockSize = 0; // block size // last graphic control extension info private int dispose = 0; // 0=no action; 1=leave in place; 2=restore to bg; 3=restore to prev private int lastDispose = 0; private boolean transparency = false; // use transparent color private int delay = 0; // delay in milliseconds private int transIndex; // transparent color index private static final int MaxStackSize = 4096; // max decoder pixel stack size // LZW decoder working arrays private short[] prefix; private byte[] suffix; private byte[] pixelStack; private byte[] pixels; private GifFrame gifFrame; // frames read from current file private int frameCount; private GifAction action = null; private byte[] gifData = null; public GifDecoder(byte[] data,GifAction act){ gifData = data; action = act; } public GifDecoder(InputStream is,GifAction act){ in = is; action = act; } public void run(){ if(in != null){ readStream(); }else if(gifData != null){ readByte(); } } /** * 释放资源 */ public void free(){ GifFrame fg = gifFrame; while(fg != null){ fg.image = null; fg = null; gifFrame = gifFrame.nextFrame; fg = gifFrame; } if(in != null){ try{ in.close(); }catch(Exception ex){} in = null; } gifData = null; } /** * 当前状态 * @return */ public int getStatus(){ return status; } /** * 解码是否成功，成功返回true * @return 成功返回true，否则返回false */ public boolean parseOk(){ return status == STATUS_FINISH; } /** * 取某帧的延时时间 * @param n 第几帧 * @return 延时时间，毫秒 */ public int getDelay(int n) { delay = -1; if ((n >= 0) && (n < frameCount)) { // delay = ((GifFrame) frames.elementAt(n)).delay; GifFrame f = getFrame(n); if (f != null) delay = f.delay; } return delay; } /** * 取所有帧的延时时间 * @return */ public int[] getDelays(){ GifFrame f = gifFrame; int[] d = new int[frameCount]; int i = 0; while(f != null && i < frameCount){ d[i] = f.delay; f = f.nextFrame; i++; } return d; } /** * 取总帧 数 * @return 图片的总帧数 */ public int getFrameCount() { return frameCount; } /** * 取第一帧图片 * @return */ public Bitmap getImage() { return getFrameImage(0); } public int getLoopCount() { return loopCount; } private void setPixels() { int[] dest = new int[width * height]; // fill in starting image contents based on last image's dispose code if (lastDispose > 0) { if (lastDispose == 3) { // use image before last int n = frameCount - 2; if (n > 0) { lastImage = getFrameImage(n - 1); } else { lastImage = null; } } if (lastImage != null) { lastImage.getPixels(dest, 0, width, 0, 0, width, height); // copy pixels if (lastDispose == 2) { // fill last image rect area with background color int c = 0; if (!transparency) { c = lastBgColor; } for (int i = 0; i < lrh; i++) { int n1 = (lry + i) * width + lrx; int n2 = n1 + lrw; for (int k = n1; k < n2; k++) { dest[k] = c; } } } } } // copy each source line to the appropriate place in the destination int pass = 1; int inc = 8; int iline = 0; for (int i = 0; i < ih; i++) { int line = i; if (interlace) { if (iline >= ih) { pass++; switch (pass) { case 2: iline = 4; break; case 3: iline = 2; inc = 4; break; case 4: iline = 1; inc = 2; } } line = iline; iline += inc; } line += iy; if (line < height) { int k = line * width; int dx = k + ix; // start of line in dest int dlim = dx + iw; // end of dest line if ((k + width) < dlim) { dlim = k + width; // past dest edge } int sx = i * iw; // start of line in source while (dx < dlim) { // map color and insert in destination int index = ((int) pixels[sx++]) & 0xff; int c = act[index]; if (c != 0) { dest[dx] = c; } dx++; } } } image = Bitmap.createBitmap(dest, width, height, Config.ARGB_4444); } /** * 取第几帧的图片 * @param n 帧数 * @return 可画的图片，如果没有此帧或者出错，返回null */ public Bitmap getFrameImage(int n) { GifFrame frame = getFrame(n); if (frame == null) return null; else return frame.image; } /** * 取当前帧图片 * @return 当前帧可画的图片 */ public GifFrame getCurrentFrame(){ return currentFrame; } /** * 取第几帧，每帧包含了可画的图片和延时时间 * @param n 帧数 * @return */ public GifFrame getFrame(int n) { GifFrame frame = gifFrame; int i = 0; while (frame != null) { if (i == n) { return frame; } else { frame = frame.nextFrame; } i++; } return null; } /** * 重置，进行本操作后，会直接到第一帧 */ public void reset(){ currentFrame = gifFrame; } /** * 下一帧，进行本操作后，通过getCurrentFrame得到的是下一帧 * @return 返回下一帧 */ public GifFrame next() { if(isShow == false){ isShow = true; return gifFrame; }else{ if(status == STATUS_PARSING){ if(currentFrame.nextFrame != null) currentFrame = currentFrame.nextFrame; //currentFrame = gifFrame; }else{ currentFrame = currentFrame.nextFrame; if (currentFrame == null) { currentFrame = gifFrame; } } return currentFrame; } } private int readByte(){ in = new ByteArrayInputStream(gifData); gifData = null; return readStream(); } // public int read(byte[] data){ // InputStream is = new ByteArrayInputStream(data); // return read(is); // } private int readStream(){ init(); if(in != null){ readHeader(); if(!err()){ readContents(); if(frameCount < 0){ status = STATUS_FORMAT_ERROR; action.parseOk(false