Gif图片压缩、水印处理

gif的图片处理一直很头痛，因为sun没有给出动态图片的开发包。网上找到的一些类，修改了部分代码，基本能用，但某些GIF中定义的动作处理还有问题。

 

 

AnimatedGifEncoder.java

 

import java.io.*;import java.awt.*;import java.awt.image.*;/** * Class AnimatedGifEncoder - Encodes a GIF file consisting of one or more * frames. * * <pre> * Example: * AnimatedGifEncoder e = new AnimatedGifEncoder(); * e.start(outputFileName); * e.setDelay(1000); // 1 frame per sec * e.addFrame(image1); * e.addFrame(image2); * e.finish(); * </pre> * * No copyright asserted on the source code of this class. May be used for any * purpose, however, refer to the Unisys LZW patent for restrictions on use of * the associated LZWEncoder class. Please forward any corrections to * [e-mail]. * * @author Kevin Weiner, FM Software * @version 1.03 November 2003 * */public class AnimatedGifEncoder {protected int width; // image sizeprotected int height;protected Color transparent = null; // transparent color if givenprotected int transIndex; // transparent index in color tableprotected int repeat = -1; // no repeatprotected int delay = 0; // frame delay (hundredths)protected boolean started = false; // ready to output framesprotected OutputStream out;protected BufferedImage image; // current frameprotected byte[] pixels; // BGR byte array from frameprotected byte[] indexedPixels; // converted frame indexed to paletteprotected int colorDepth; // number of bit planesprotected byte[] colorTab; // RGB paletteprotected boolean[] usedEntry = new boolean[256]; // active palette// entriesprotected int palSize = 7; // color table size (bits-1)protected int dispose = -1; // disposal code (-1 = use default)protected boolean closeStream = false; // close stream when finishedprotected boolean firstFrame = true;protected boolean sizeSet = false; // if false, get size from first frameprotected int sample = 10; // default sample interval for quantizerprotected int bgIndex; // background color indexprotected Color bgColor=null; // background color/** * Sets the delay time between each frame, or changes it for subsequent * frames (applies to last frame added). * * @param ms * int delay time in milliseconds */public void setDelay(int ms) {delay = Math.round(ms / 10.0f);}/** * 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 void setDispose(int code) {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 void setRepeat(int iter) {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 c * Color to be treated as transparent on display. */public void setTransparent(Color c) {transparent = c;}public void setBgColor(Color c) {bgColor = c;}/** * Adds next GIF frame. The frame is not written immediately, but is * actually deferred until the next frame is received so that timing data * can be inserted. Invoking <code>finish()</code> flushes all frames. If * <code>setSize</code> was not invoked, the size of the first image is * used for all subsequent frames. * * @param im * BufferedImage containing frame to write. * @return true if successful. */public boolean addFrame(BufferedImage im) {if ((im == null) || !started) {return false;}boolean ok = true;try {if (!sizeSet) {// use first frame's sizesetSize(im.getWidth(), im.getHeight());}image = im;getImagePixels(); // convert to correct format if necessaryanalyzePixels(); // build color table & map pixelsif (firstFrame) {writeLSD(); // logical screen descriptiorwritePalette(); // global color tableif (repeat >= 0) {// use NS app extension to indicate repswriteNetscapeExt();}}writeGraphicCtrlExt(); // write graphic control extensionwriteImageDesc(); // image descriptorif (!firstFrame) {writePalette(); // local color table}writePixels(); // encode and write pixel datafirstFrame = false;} catch (IOException e) {ok = false;}return ok;}/** * Flushes any pending data and closes output file. If writing to an * OutputStream, the stream is not closed. */public boolean finish() {if (!started)return false;boolean ok = true;started = false;try {out.write(0x3b); // gif trailerout.flush();if (closeStream) {out.close();}} catch (IOException e) {ok = false;}// reset for subsequent usetransIndex = 0;out = null;image = null;pixels = null;indexedPixels = null;colorTab = null;closeStream = false;firstFrame = true;bgIndex=0;return ok;}/** * Sets frame rate in frames per second. Equivalent to * <code>setDelay(1000/fps)</code>. * * @param fps * float frame rate (frames per second) */public void setFrameRate(float fps) {if (fps != 0f) {delay = Math.round(100f / 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 void setQuality(int quality) {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. */public void setSize(int w, int h) {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. The stream is not closed * automatically. * * @param os * OutputStream on which GIF images are written. * @return false if initial write failed. */public boolean start(OutputStream os) {if (os == null)return false;boolean ok = true;closeStream = false;out = os;try {writeString("GIF89a"); // header} catch (IOException e) {ok = false;}return started = ok;}/** * Initiates writing of a GIF file with the specified name. * * @param file * String containing output file name. * @return false if open or initial write failed. */public boolean start(String file) {boolean ok = true;try {out = new BufferedOutputStream(new FileOutputStream(file));ok = start(out);closeStream = true;} catch (IOException e) {ok = false;}return started = ok;}/** * Analyzes image colors and creates color map. */protected void analyzePixels() {int len = pixels.length;int nPix = len / 3;indexedPixels = new byte[nPix];NeuQuant nq = new NeuQuant(pixels, len, sample);// initialize quantizercolorTab = nq.process(); // create reduced palette// convert map from BGR to RGBfor (int i = 0; i < colorTab.length; i += 3) {byte temp = colorTab[i];colorTab[i] = colorTab[i + 2];colorTab[i + 2] = temp;usedEntry[i / 3] = false;}// map image pixels to new paletteint k = 0;for (int i = 0; i < nPix; i++) {int index = nq.map(pixels[k++] & 0xff, pixels[k++] & 0xff,pixels[k++] & 0xff);usedEntry[index] = true;indexedPixels[i] = (byte) index;}pixels = null;colorDepth = 8;palSize = 7;// get closest match to transparent color if specifiedif (transparent != null) {transIndex = findClosest(transparent);}if ( bgColor != null) {bgIndex = findClosest(bgColor);}}/** * Returns index of palette color closest to c * */protected int findClosest(Color c) {if (colorTab == null)return -1;int r = c.getRed();int g = c.getGreen();int b = c.getBlue();int minpos = 0;int dmin = 256 * 256 * 256;int len = usedEntry.length;for (int i = 0; i < len; i++) {if (usedEntry[i]){int dr = r - (colorTab[3*i] & 0xff);int dg = g - (colorTab[3*i+1] & 0xff);int db = b - (colorTab[3*i+2] & 0xff);int d = dr * dr + dg * dg + db * db;if (d < dmin) {dmin = d;minpos = i;}}}/*int len = colorTab.length;for (int i = 0; i < len;) {int dr = r - (colorTab[i++] & 0xff);int dg = g - (colorTab[i++] & 0xff);int db = b - (colorTab[i] & 0xff);int d = dr * dr + dg * dg + db * db;int index = i / 3;if (usedEntry[index] && (d < dmin)) {dmin = d;minpos = index;}i++;}*/return minpos;}/** * Extracts image pixels into byte array "pixels" */protected void getImagePixels() {int w = image.getWidth();int h = image.getHeight();int type = image.getType();if ((w != width) || (h != height)|| (type != BufferedImage.TYPE_3BYTE_BGR)) {// create new image with right size/formatBufferedImage temp = new BufferedImage(width, height,BufferedImage.TYPE_3BYTE_BGR);Graphics2D g = temp.createGraphics();g.drawImage(image, 0, 0, null);image = temp;}pixels = ((DataBufferByte) image.getRaster().getDataBuffer()).getData();}/** * Writes Graphic Control Extension */protected void writeGraphicCtrlExt() throws IOException {out.write(0x21); // extension introducerout.write(0xf9); // GCE labelout.write(4); // data block sizeint transp, disp=0;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 fieldsout.write(0 | // 1:3 reserveddisp | // 4:6 disposal0 | // 7 user input - 0 = nonetransp); // 8 transparency flagwriteShort(delay); // delay x 1/100 secout.write(transIndex); // transparent color indexout.write(0); // block terminator}/** * Writes Image Descriptor */protected void writeImageDesc() throws IOException {out.write(0x2c); // image separatorwriteShort(0); // image position x,y = 0,0writeShort(0);writeShort(width); // image sizewriteShort(height);// packed fieldsif (firstFrame) {// no LCT - GCT is used for first (or only) frameout.write(0);} else {// specify normal LCTout.write(0x80 | // 1 local color table 1=yes0 | // 2 interlace - 0=no0 | // 3 sorted - 0=no0 | // 4-5 reservedpalSize); // 6-8 size of color table}}/** * Writes Logical Screen Descriptor */protected void writeLSD() throws IOException {// logical screen sizewriteShort(width);writeShort(height);// packed fieldsout.write((0x80 | // 1 : global color table flag = 1 (gct used)0x70 | // 2-4 : color resolution = 70x00 | // 5 : gct sort flag = 0palSize)); // 6-8 : gct sizeout.write(bgIndex); // background color indexout.write(0); // pixel aspect ratio - assume 1:1}/** * Writes Netscape application extension to define repeat count. */protected void writeNetscapeExt() throws IOException {out.write(0x21); // extension introducerout.write(0xff); // app extension labelout.write(11); // block sizewriteString("NETSCAPE" + "2.0"); // app id + auth codeout.write(3); // sub-block sizeout.write(1); // loop sub-block idwriteShort(repeat); // loop count (extra iterations, 0=repeat forever)out.write(0); // block terminator}/** * Writes color table */protected void writePalette() throws IOException {out.write(colorTab, 0, colorTab.length);int n = (3 * 256) - colorTab.length;for (int i = 0; i < n; i++) {out.write(0);}}/** * Encodes and writes pixel data */protected void writePixels() throws IOException {LZWEncoder encoder = new LZWEncoder(width, height, indexedPixels,colorDepth);encoder.encode(out);}/** * Write 16-bit value to output stream, LSB first */protected void writeShort(int value) throws IOException {out.write(value & 0xff);out.write((value >> 8) & 0xff);}/** * Writes string to output stream */protected void writeString(String s) throws IOException {for (int i = 0; i < s.length(); i++) {out.write((byte) s.charAt(i));}}}

 

AnimatedGifDecoder.java

 

import java.awt.AlphaComposite;import java.awt.Color;import java.awt.Dimension;import java.awt.Graphics2D;import java.awt.Rectangle;import java.awt.image.BufferedImage;import java.awt.image.DataBufferInt;import java.io.BufferedInputStream;import java.io.FileInputStream;import java.io.IOException;import java.io.InputStream;import java.net.URL;import java.util.ArrayList;import java.util.List;//格式说明：http://blog.csdn.net/friendwaters/archive/2008/07/30/2737328.aspxpublic class AnimatedGifDecoder {/** * File read status: No errors. */public static final int STATUS_OK = 0;/** * File read status: Error decoding file (may be partially decoded) */public static final int STATUS_FORMAT_ERROR = 1;/** * File read status: Unable to open source. */public static final int STATUS_OPEN_ERROR = 2;protected BufferedInputStream in;protected int status;protected int width; // full image widthprotected int height; // full image heightprotected boolean gctFlag; // global color table usedprotected int gctSize; // size of global color tableprotected int loopCount = 1; // iterations; 0 = repeat foreverprotected int[] gct; // global color tableprotected int[] lct; // local color tableprotected int[] act; // active color table//protected int lastBgColor; // previous bg colorprotected int pixelAspect; // pixel aspect ratioprotected boolean lctFlag; // local color table flagprotected boolean interlace; // interlace flagprotected int lctSize; // local color table sizeprotected int ix, iy, iw, ih; // current image rectangleprotected Rectangle lastRect; // last image rectprotected BufferedImage image; // current frameprotected BufferedImage lastImage; // previous frameprotected byte[] block = new byte[256]; // current data blockprotected int blockSize = 0; // block size// last graphic control extension infoprotected int dispose = 0;// 0=no action; 1=leave in place; 2=restore to bg; 3=restore to prevprotected Color transColor = null; // use transparent colorprotected int transIndex = -1;protected int bgIndex = -1; // background color indexprotected Color bgColor = null; // background colorprotected int delay = 0; // delay in millisecondsprotected static final int MaxStackSize = 4096;// max decoder pixel stack size// LZW decoder working arraysprotected short[] prefix;protected byte[] suffix;protected byte[] pixelStack;protected byte[] pixels;protected List<GifFrame> frames; // frames read from current fileprotected int frameCount;static class GifFrame {public GifFrame(BufferedImage im, int del,Color transColor,int dispose) {this.image = im;this.delay = del;this.transColor = transColor;this.dispose = dispose;}public BufferedImage image;public int delay;public Color transColor;public int dispose;}/** * Gets display duration for specified frame. * * @param n * int index of frame * @return delay in milliseconds */public int getDelay(int n) {//int delay = -1;if ( n >= 0 && n < frameCount ) {delay = frames.get(n).delay;}return delay;}public Color getTrans(int n) {Color transColor = null;if ( n >= 0 && n < frameCount ) {transColor = frames.get(n).transColor;}return transColor;}public int getDispose(int n) {int dispose = 0;if ( n >= 0 && n < frameCount ) {dispose = frames.get(n).dispose;}return dispose;}/** * Gets the image contents of frame n. * * @return BufferedImage representation of frame, or null if n is invalid. */public BufferedImage getFrame(int n) {BufferedImage im = null;if ((n >= 0) && (n < frameCount)) {im = frames.get(n).image;}return im;}/** * Gets the number of frames read from file. * * @return frame count */public int getFrameCount() {return frameCount;}/** * Gets the first (or only) image read. * * @return BufferedImage containing first frame, or null if none. */public BufferedImage getImage() {return getFrame(0);}/** * Gets the "Netscape" iteration count, if any. A count of 0 means repeat * indefinitiely. * * @return iteration count if one was specified, else 1. */public int getLoopCount() {return loopCount;}/** * Creates new frame image from current data (and previous frames as * specified by their disposition codes). */protected void setPixels() {if (transIndex >= 0 ) {int tr = (act[transIndex]>> 16) & 0xFF;int tg = (act[transIndex]>> 8) & 0xFF;int tb = (act[transIndex]>> 0) & 0xFF;transColor = new Color(tr,tg,tb,0);} else {transColor = null;}// expose destination image's pixels as int arrayint[] dest = ((DataBufferInt) image.getRaster().getDataBuffer()).getData();// fill in starting image contents based on last image's dispose codeif (dispose > 0) { //0 - 不使用处置方法if (dispose == 1) { //1 - 不处置图形，图形保持不变if (lastImage != null) {int[] prev = ((DataBufferInt) lastImage.getRaster().getDataBuffer()).getData();System.arraycopy(prev, 0, dest, 0, width * height);}}else if (dispose == 2) { //2=回复到背景色// fill last image rect area with background colorGraphics2D g = image.createGraphics();Color c = null;//if (transColor != null ) {//c = transColor;//} else if (bgIndex >= 0) {c = bgColor; // use given background color}else {c = new Color(0,0,0,0); //Color.black;}g.setColor(c);g.setComposite(AlphaComposite.Src); // replace areag.fill(lastRect);g.dispose();}else if (dispose == 3) { // 3 - 回复到前桢图像// use image before lastint n = frameCount - 2;if (n > 0) {lastImage = getFrame(n - 1);int[] prev = ((DataBufferInt) lastImage.getRaster().getDataBuffer()).getData();System.arraycopy(prev, 0, dest, 0, width * height);}}}// copy each source line to the appropriate place in the destinationint 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 destint dlim = dx + iw; // end of dest lineif ((k + width) < dlim) {dlim = k + width; // past dest edge}int sx = i * iw; // start of line in sourcewhile (dx < dlim) {// map color and insert in destinationint index = ((int) pixels[sx++]) & 0xff;int c = act[index];if (c != 0) {dest[dx] = c;}dx++;}}}}/** * Gets image size. * * @return GIF image dimensions */public Dimension getFrameSize() {return new Dimension(width, height);}/** * Reads GIF image from stream * * @param BufferedInputStream * containing GIF file. * @return read status code (0 = no errors) */public int read(BufferedInputStream is) {init();if (is != null) {in = is;readHeader();if (!err()) {readContents();if (frameCount < 0) {status = STATUS_FORMAT_ERROR;}}} else {status = STATUS_OPEN_ERROR;}try {is.close();} catch (IOException e) {}return status;}/** * Reads GIF image from stream * * @param InputStream * containing GIF file. * @return read status code (0 = no errors) */public int read(InputStream is) {init();if (is != null) {if (!(is instanceof BufferedInputStream))is = new BufferedInputStream(is);in = (BufferedInputStream) is;readHeader();if (!err()) {readContents();if (frameCount < 0) {status = STATUS_FORMAT_ERROR;}}} else {status = STATUS_OPEN_ERROR;}try {is.close();} catch (IOException e) {}return status;}/** * Reads GIF file from specified file/URL source (URL assumed if name * contains ":/" or "file:") * * @param name * String containing source * @return read status code (0 = no errors) */public int read(String name) {status = STATUS_OK;try {name = name.trim().toLowerCase();if ((name.indexOf("file:") >= 0) || (name.indexOf(":/") > 0)) {URL url = new URL(name);in = new BufferedInputStream(url.openStream());} else {in = new BufferedInputStream(new FileInputStream(name));}status = read(in);} catch (IOException e) {status = STATUS_OPEN_ERROR;}return status;}/** * Decodes LZW image data into pixel array. Adapted from John Cristy's * ImageMagick. */protected void decodeImageData() {int NullCode = -1;int npix = iw * ih;int available, clear, code_mask, code_size, end_of_information, in_code, old_code, bits, code, count, i, datum, data_size, first, top, bi, pi;if ((pixels == null) || (pixels.length < npix)) {pixels = new byte[npix]; // allocate new pixel array}if (prefix == null)prefix = new short[MaxStackSize];if (suffix == null)suffix = new byte[MaxStackSize];if (pixelStack == null)pixelStack = new byte[MaxStackSize + 1];// Initialize GIF data stream decoder.data_size = read();clear = 1 << data_size;end_of_information = clear + 1;available = clear + 2;old_code = NullCode;code_size = data_size + 1;code_mask = (1 << code_size) - 1;for (code = 0; code < clear; code++) {prefix[code] = 0;suffix[code] = (byte) code;}// Decode GIF pixel stream.datum = bits = count = first = top = pi = bi = 0;for (i = 0; i < npix;) {if (top == 0) {if (bits < code_size) {// Load bytes until there are enough bits for a code.if (count == 0) {// Read a new data block.count = readBlock();if (count <= 0)break;bi = 0;}datum += (((int) block[bi]) & 0xff) << bits;bits += 8;bi++;count--;continue;}// Get the next code.code = datum & code_mask;datum >>= code_size;bits -= code_size;// Interpret the codeif ((code > available) || (code == end_of_information))break;if (code == clear) {// Reset decoder.code_size = data_size + 1;code_mask = (1 << code_size) - 1;available = clear + 2;old_code = NullCode;continue;}if (old_code == NullCode) {pixelStack[top++] = suffix[code];old_code = code;first = code;continue;}in_code = code;if (code == available) {pixelStack[top++] = (byte) first;code = old_code;}while (code > clear) {pixelStack[top++] = suffix[code];code = prefix[code];}first = ((int) suffix[code]) & 0xff;// Add a new string to the string table,if (available >= MaxStackSize)break;pixelStack[top++] = (byte) first;prefix[available] = (short) old_code;suffix[available] = (byte) first;available++;if (((available & code_mask) == 0)&& (available < MaxStackSize)) {code_size++;code_mask += available;}old_code = in_code;}// Pop a pixel off the pixel stack.top--;pixels[pi++] = pixelStack[top];i++;}for (i = pi; i < npix; i++) {pixels[i] = 0; // clear missing pixels}}/** * Returns true if an error was encountered during reading/decoding */protected boolean err() {return status != STATUS_OK;}/** * Initializes or re-initializes reader */protected void init() {status = STATUS_OK;frameCount = 0;frames = new ArrayList<GifFrame>();gct = null;lct = null;}/** * Reads a single byte from the input stream. */protected int read() {int curByte = 0;try {curByte = in.read();} catch (IOException e) {status = STATUS_FORMAT_ERROR;}return curByte;}/** * Reads next variable length block from input. * * @return number of bytes stored in "buffer" */protected int readBlock() {blockSize = read();int n = 0;if (blockSize > 0) {try {int count = 0;while (n < blockSize) {count = in.read(block, n, blockSize - n);if (count == -1)break;n += count;}} catch (IOException e) {}if (n < blockSize) {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) */protected int[] readColorTable(int ncolors) {int nbytes = 3 * ncolors;int[] tab = null;byte[] c = new byte[nbytes];int n = 0;try {n = in.read(c);} catch (IOException e) {}if (n < nbytes) {status = STATUS_FORMAT_ERROR;} else {tab = new int[256]; // max size to avoid bounds checksint i = 0;int j = 0;while (i < ncolors) {int r = ((int) c[j++]) & 0xff;int g = ((int) c[j++]) & 0xff;int b = ((int) c[j++]) & 0xff;tab[i++] = 0xff000000 | (r << 16) | (g << 8) | b;}}return tab;}/** * Main file parser. Reads GIF content blocks. */protected void readContents() {// read GIF file content blocksboolean done = false;while (!(done || err())) {int code = read();switch (code) {case 0x2C: // image separatorreadImage();break;case 0x21: // extensioncode = read();switch (code) {case 0xf9: // graphics control extensionreadGraphicControlExt();break;case 0xff: // application extensionreadBlock();String app = "";for (int i = 0; i < 11; i++) {app += (char) block[i];}if (app.equals("NETSCAPE2.0")) {readNetscapeExt();} elseskip(); // don't carebreak;default: // uninteresting extensionskip();}break;case 0x3b: // terminatordone = true;break;case 0x00: // bad byte, but keep going and see what happensbreak;default:status = STATUS_FORMAT_ERROR;}}}/** * Reads Graphics Control Extension values */protected void readGraphicControlExt() {read(); // block sizeint packed = read(); // packed fieldsdispose = (packed & 0x1c) >> 2; // disposal method/*if (dispose == 0) {dispose = 1; // elect to keep old image if discretionary}*/delay = readShort() * 10; // delay in millisecondstransIndex = read(); // transparent color indexif ((packed & 1) == 0){transIndex = -1;}read(); // block terminator}/** * Reads GIF file header information. */protected void readHeader() {String id = "";for (int i = 0; i < 6; i++) {id += (char) read();}if (!id.startsWith("GIF")) {status = STATUS_FORMAT_ERROR;return;}readLSD();}/** * Reads next frame image */protected void readImage() {ix = readShort(); // (sub)image position & sizeiy = readShort();iw = readShort();ih = readShort();int packed = read();lctFlag = (packed & 0x80) != 0; // 1 - local color table flaginterlace = (packed & 0x40) != 0; // 2 - interlace flag// 3 - sort flag// 4-5 - reservedlctSize = 2 << (packed & 7); // 6-8 - local color table sizeif (lctFlag) {lct = readColorTable(lctSize); // read tableact = lct; // make local table active} else {act = gct; // make global table active//if (transparency && bgIndex == transIndex)//bgColor = 0;}/*int save = 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 (err())return;decodeImageData(); // decode pixel dataskip();if (err())return;frameCount++;// create new image to receive frame dataimage = new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB_PRE);setPixels(); // transfer pixel data to imageframes.add(new GifFrame(image, delay, transColor, dispose)); // add image to frame list/*if (transparency) {act[transIndex] = save;}*/resetFrame();}/** * Reads Logical Screen Descriptor */protected void readLSD() {// logical screen sizewidth = readShort();height = readShort();lastRect = new Rectangle(0, 0, width, height);// packed fieldsint packed = read();gctFlag = (packed & 0x80) != 0; // 1 : global color table flag// 2-4 : color resolution// 5 : gct sort flaggctSize = 2 << (packed & 7); // 6-8 : gct sizebgIndex = read(); // background color indexpixelAspect = read(); // pixel aspect ratioif (gctFlag && !err()) {gct = readColorTable(gctSize);int tr = (gct[bgIndex]>> 16) & 0xFF;int tg = (gct[bgIndex]>> 8) & 0xFF;int tb = (gct[bgIndex]>> 0) & 0xFF;bgColor = new Color(tr,tg,tb,255);}}/** * Reads Netscape extenstion to obtain iteration count */protected void readNetscapeExt() {do {readBlock();if (block[0] == 1) {// loop count sub-blockint b1 = ((int) block[1]) & 0xff;int b2 = ((int) block[2]) & 0xff;loopCount = (b2 << 8) | b1;}} while ((blockSize > 0) && !err());}/** * Reads next 16-bit value, LSB first */protected int readShort() {// read 16-bit value, LSB firstreturn read() | (read() << 8);}/** * Resets frame state for reading next image. */protected void resetFrame() {lastRect = new Rectangle(ix, iy, iw, ih);lastImage = image;//lastBgColor = bgColor;//dispose = 0;//transparency = false;//delay = 0;lct = null;}protected void skip() {do {readBlock();} while ((blockSize > 0) && !err());}}

 

LZWEncoder.java 

  import java.io.OutputStream;import java.io.IOException;//==============================================================================// Adapted from Jef Poskanzer's Java port by way of J. M. G. Elliott.// K Weiner 12/00class LZWEncoder {private static final int EOF = -1;private int imgW, imgH;private byte[] pixAry;private int initCodeSize;private int remaining;private int curPixel;// GIFCOMPR.C - GIF Image compression routines//// Lempel-Ziv compression based on 'compress'. GIF modifications by// David Rowley ([e-mail])// General DEFINEsstatic final int BITS = 12;static final int HSIZE = 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)int n_bits; // number of bits/codeint maxbits = BITS; // user settable max # bits/codeint maxcode; // maximum code, given n_bitsint maxmaxcode = 1 << BITS; // should NEVER generate this codeint[] htab = new int[HSIZE];int[] codetab = new int[HSIZE];int hsize = HSIZE; // for dynamic table sizingint free_ent = 0; // first unused entry// block compression parameters -- after all codes are used up,// and compression rate changes, start over.boolean clear_flg = 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.int g_init_bits;int ClearCode;int EOFCode;// 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.int cur_accum = 0;int cur_bits = 0;int masks[] = { 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'int a_count;// Define the storage for the packet accumulatorbyte[] accum = new byte[256];// ----------------------------------------------------------------------------LZWEncoder(int width, int height, byte[] pixels, int color_depth) {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.void char_out(byte c, OutputStream outs) throws IOException {accum[a_count++] = c;if (a_count >= 254)flush_char(outs);}// Clear out the hash table// table clear for block compressvoid cl_block(OutputStream outs) throws IOException {cl_hash(hsize);free_ent = ClearCode + 2;clear_flg = true;output(ClearCode, outs);}// reset code tablevoid cl_hash(int hsize) {for (int i = 0; i < hsize; ++i)htab[i] = -1;}void compress(int init_bits, OutputStream outs) throws IOException {int fcode;int i /* = 0 */;int c;int ent;int disp;int hsize_reg;int hshift;// Set up the globals: g_init_bits - initial number of bitsg_init_bits = init_bits;// Set up the necessary valuesclear_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 packetent = nextPixel();hshift = 0;for (fcode = hsize; fcode < 65536; fcode *= 2)++hshift;hshift = 8 - hshift; // set hash code range boundhsize_reg = hsize;cl_hash(hsize_reg); // clear hash tableoutput(ClearCode, outs);outer_loop: while ((c = nextPixel()) != EOF) {fcode = (c << maxbits) + ent;i = (c << hshift) ^ ent; // xor hashingif (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 -> hashtablehtab[i] = fcode;} elsecl_block(outs);}// Put out the final code.output(ent, outs);output(EOFCode, outs);}// ----------------------------------------------------------------------------void encode(OutputStream os) throws IOException {os.write(initCodeSize); // write "initial code size" byteremaining = imgW * imgH; // reset navigation variablescurPixel = 0;compress(initCodeSize + 1, os); // compress and write the pixel dataos.write(0); // write block terminator}// Flush the packet to disk, and reset the accumulatorvoid flush_char(OutputStream outs) throws IOException {if (a_count > 0) {outs.write(a_count);outs.write(accum, 0, a_count);a_count = 0;}}final int MAXCODE(int n_bits) {return (1 << n_bits) - 1;}// ----------------------------------------------------------------------------// Return the next pixel from the image// ----------------------------------------------------------------------------private int nextPixel() {if (remaining == 0)return EOF;--remaining;byte pix = pixAry[curPixel++];return pix & 0xff;}void output(int code, OutputStream outs) throws IOException {cur_accum &= masks[cur_bits];if (cur_bits > 0)cur_accum |= (code << cur_bits);elsecur_accum = code;cur_bits += n_bits;while (cur_bits >= 8) {char_out((byte) (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;elsemaxcode = MAXCODE(n_bits);}}if (code == EOFCode) {// At EOF, write the rest of the buffer.while (cur_bits > 0) {char_out((byte) (cur_accum & 0xff), outs);cur_accum >>= 8;cur_bits -= 8;}flush_char(outs);}}}

 

NeuQuant.java

 

 /* 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. */// Ported to Java 12/00 K Weinerpublic class NeuQuant {protected static final int netsize = 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 */protected static final int prime1 = 499;protected static final int prime2 = 491;protected static final int prime3 = 487;protected static final int prime4 = 503;protected static final int minpicturebytes = (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 ------------------- */protected static final int maxnetpos = (netsize - 1);protected static final int netbiasshift = 4; /* bias for colour values */protected static final int ncycles = 100; /* no. of learning cycles *//* defs for freq and bias */protected static final int intbiasshift = 16; /* bias for fractions */protected static final int intbias = (((int) 1) << intbiasshift);protected static final int gammashift = 10; /* gamma = 1024 */protected static final int gamma = (((int) 1) << gammashift);protected static final int betashift = 10;protected static final int beta = (intbias >> betashift); /* beta = 1/1024 */protected static final int betagamma = (intbias << (gammashift - betashift));/* defs for decreasing radius factor */protected static final int initrad = (netsize >> 3); /* * for 256 cols, * radius starts */protected static final int radiusbiasshift = 6; /* at 32.0 biased by 6 bits */protected static final int radiusbias = (((int) 1) << radiusbiasshift);protected static final int initradius = (initrad * radiusbias); /* * and * decreases * by a */protected static final int radiusdec = 30; /* factor of 1/30 each cycle *//* defs for decreasing alpha factor */protected static final int alphabiasshift = 10; /* alpha starts at 1.0 */protected static final int initalpha = (((int) 1) << alphabiasshift);protected int alphadec; /* biased by 10 bits *//* radbias and alpharadbias used for radpower calculation */protected static final int radbiasshift = 8;protected static final int radbias = (((int) 1) << radbiasshift);protected static final int alpharadbshift = (alphabiasshift + radbiasshift);protected static final int alpharadbias = (((int) 1) << alpharadbshift);/* * Types and Global Variables -------------------------- */protected byte[] thepicture; /* the input image itself */protected int lengthcount; /* lengthcount = H*W*3 */protected int samplefac; /* sampling factor 1..30 */// typedef int pixel[4]; /* BGRc */protected int[][] network; /* the network itself - [netsize][4] */protected int[] netindex = new int[256];/* for network lookup - really 256 */protected int[] bias = new int[netsize];/* bias and freq arrays for learning */protected int[] freq = new int[netsize];protected int[] radpower = new int[initrad];/* radpower for precomputation *//* * Initialise network in range (0,0,0) to (255,255,255) and set parameters * ----------------------------------------------------------------------- */public NeuQuant(byte[] thepic, int len, int sample) {int i;int[] p;thepicture = thepic;lengthcount = len;samplefac = sample;network = new int[netsize][];for (i = 0; i < netsize; i++) {network[i] = new int[4];p = network[i];p[0] = p[1] = p[2] = (i << (netbiasshift + 8)) / netsize;freq[i] = intbias / netsize; /* 1/netsize */bias[i] = 0;}}public byte[] colorMap() {byte[] map = new byte[3 * netsize];int[] index = new int[netsize];for (int i = 0; i < netsize; i++)index[network[i][3]] = i;int k = 0;for (int i = 0; i < netsize; i++) {int j = index[i];map[k++] = (byte) (network[j][0]);map[k++] = (byte) (network[j][1]);map[k++] = (byte) (network[j][2]);}return map;}/* * Insertion sort of network and building of netindex[0..255] (to do after * unbias) * ------------------------------------------------------------------------------- */public void inxbuild() {int i, j, smallpos, smallval;int[] p;int[] q;int previouscol, startpos;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 ------------------ */public void learn() {int i, j, b, g, r;int radius, rad, alpha, step, delta, samplepixels;byte[] p;int pix, lim;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));// fprintf(stderr,"beginning 1D learning: initial radius=%d/n", 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;elsestep = 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));}}// fprintf(stderr,"finished 1D learning: final alpha=%f// !/n",((float)alpha)/initalpha);}/* * Search for BGR values 0..255 (after net is unbiased) and return colour * index * ---------------------------------------------------------------------------- */public int map(int b, int g, int r) {int i, j, dist, a, bestd;int[] p;int best;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 byte[] process() {learn();unbiasnet();inxbuild();return colorMap();}/* * Unbias network to give byte values 0..255 and record position i to * prepare for sort * ----------------------------------------------------------------------------------- */public void unbiasnet() {int i, j;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|] * --------------------------------------------------------------------------------- */protected void alterneigh(int rad, int i, int b, int g, int r) {int j, k, lo, hi, a, m;int[] p;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 (Exception e) {} // 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 (Exception e) {}}}}/* * Move neuron i towards biased (b,g,r) by factor alpha * ---------------------------------------------------- */protected void altersingle(int alpha, int i, int b, int g, int r) {/* alter hit neuron */int[] n = 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 ---------------------------- */protected int contest(int b, int g, int r) {/* 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]) */int i, dist, a, biasdist, betafreq;int bestpos, bestbiaspos, bestd, bestbiasd;int[] n;bestd = ~(((int) 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);}}

 

 

GIf处理

import java.awt.Color;import java.awt.image.BufferedImage;import java.io.FileOutputStream;import javax.imageio.ImageIO;import com.sun.image.codec.jpeg.JPEGCodec;import com.sun.image.codec.jpeg.JPEGImageEncoder;public class gifImg {/** * @param args */public static void main(String[] args) {AnimatedGifDecoder decoder = new AnimatedGifDecoder();try {//decoder.read("777.gif"); //part//decoder.read("11.gif"); //decoder.read("xsdg2-024.gif"); //w//decoder.read("biggif.gif"); //pdecoder.read("02.gif"); //a w//decoder.read("fif004.gif");//decoder.read("06.gif");//图像处理//输出每帧图像，String path = "z";BufferedImage src[] = new BufferedImage[decoder.getFrameCount()];for (int i = 0; i < decoder.getFrameCount(); i++) {src[i] = decoder.getFrame(i); //得到帧// 生成小的JPG文件String subPic = path + i + ".png";FileOutputStream out = new FileOutputStream(subPic);ImageIO.write(src[i], "png", out);out.close();}//生成新gifAnimatedGifEncoder e = new AnimatedGifEncoder();e.setRepeat(decoder.loopCount);e.start("z.gif");if (decoder.bgColor != null)e.setBgColor(decoder.bgColor);for (int i = 0; i <src.length ; i++) {e.setDispose(decoder.getDispose(i));if (decoder.getTrans(i) != null ){e.setTransparent(decoder.getTrans(i));}e.setDelay(decoder.getDelay(i)); // 设置播放的延迟时间e.addFrame(src[i]); // 添加到帧中}e.finish();} catch (Exception e) {e.printStackTrace();}GifDecoder decoder2 = new GifDecoder();try {decoder2.read("z.gif");//图像处理//输出每帧图像，String path = "z_";BufferedImage src[] = new BufferedImage[decoder.getFrameCount()];for (int i = 0; i < decoder.getFrameCount(); i++) {src[i] = decoder.getFrame(i); //得到帧// 生成小的JPG文件String subPic = path + i + ".png";FileOutputStream out = new FileOutputStream(subPic);ImageIO.write(src[i], "png", out);out.close();}}catch (Exception e) {e.printStackTrace();}}}