diff options
Diffstat (limited to 'src/main/java/com/lowagie/text/pdf/codec/GifImage.java')
| -rw-r--r-- | src/main/java/com/lowagie/text/pdf/codec/GifImage.java | 593 |
1 files changed, 593 insertions, 0 deletions
diff --git a/src/main/java/com/lowagie/text/pdf/codec/GifImage.java b/src/main/java/com/lowagie/text/pdf/codec/GifImage.java new file mode 100644 index 0000000..f6858ac --- /dev/null +++ b/src/main/java/com/lowagie/text/pdf/codec/GifImage.java @@ -0,0 +1,593 @@ +/*
+ * Copyright 2003 by Paulo Soares.
+ *
+ * The contents of this file are subject to the Mozilla Public License Version 1.1
+ * (the "License"); you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the License.
+ *
+ * The Original Code is 'iText, a free JAVA-PDF library'.
+ *
+ * The Initial Developer of the Original Code is Bruno Lowagie. Portions created by
+ * the Initial Developer are Copyright (C) 1999, 2000, 2001, 2002 by Bruno Lowagie.
+ * All Rights Reserved.
+ * Co-Developer of the code is Paulo Soares. Portions created by the Co-Developer
+ * are Copyright (C) 2000, 2001, 2002 by Paulo Soares. All Rights Reserved.
+ *
+ * Contributor(s): all the names of the contributors are added in the source code
+ * where applicable.
+ *
+ * Alternatively, the contents of this file may be used under the terms of the
+ * LGPL license (the "GNU LIBRARY GENERAL PUBLIC LICENSE"), in which case the
+ * provisions of LGPL are applicable instead of those above. If you wish to
+ * allow use of your version of this file only under the terms of the LGPL
+ * License and not to allow others to use your version of this file under
+ * the MPL, indicate your decision by deleting the provisions above and
+ * replace them with the notice and other provisions required by the LGPL.
+ * If you do not delete the provisions above, a recipient may use your version
+ * of this file under either the MPL or the GNU LIBRARY GENERAL PUBLIC LICENSE.
+ *
+ * This library is free software; you can redistribute it and/or modify it
+ * under the terms of the MPL as stated above or under the terms of the GNU
+ * Library General Public License as published by the Free Software Foundation;
+ * either version 2 of the License, or any later version.
+ *
+ * This library is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE. See the GNU Library general Public License for more
+ * details.
+ *
+ * If you didn't download this code from the following link, you should check if
+ * you aren't using an obsolete version:
+ * http://www.lowagie.com/iText/
+ */
+package com.lowagie.text.pdf.codec;
+
+import com.lowagie.text.pdf.*;
+import com.lowagie.text.*;
+import java.io.*;
+import java.net.URL;
+import java.util.ArrayList;
+
+/** Reads gif images of all types. All the images in a gif are read in the constructors
+ * and can be retrieved with other methods.
+ * @author Paulo Soares (psoares@consiste.pt)
+ */
+public class GifImage {
+
+ protected DataInputStream in;
+ protected int width; // full image width
+ protected int height; // full image height
+ protected boolean gctFlag; // global color table used
+
+ protected int bgIndex; // background color index
+ protected int bgColor; // background color
+ protected int pixelAspect; // pixel aspect ratio
+
+ protected boolean lctFlag; // local color table flag
+ protected boolean interlace; // interlace flag
+ protected int lctSize; // local color table size
+
+ protected int ix, iy, iw, ih; // current image rectangle
+
+ protected byte[] block = new byte[256]; // current data block
+ protected int blockSize = 0; // block size
+
+ // last graphic control extension info
+ protected int dispose = 0; // 0=no action; 1=leave in place; 2=restore to bg; 3=restore to prev
+ protected boolean transparency = false; // use transparent color
+ protected int delay = 0; // delay in milliseconds
+ protected int transIndex; // transparent color index
+
+ protected static final int MaxStackSize = 4096; // max decoder pixel stack size
+
+ // LZW decoder working arrays
+ protected short[] prefix;
+ protected byte[] suffix;
+ protected byte[] pixelStack;
+ protected byte[] pixels;
+
+ protected byte m_out[];
+ protected int m_bpc;
+ protected int m_gbpc;
+ protected byte m_global_table[];
+ protected byte m_local_table[];
+ protected byte m_curr_table[];
+ protected int m_line_stride;
+ protected byte fromData[];
+ protected URL fromUrl;
+
+
+ protected ArrayList frames = new ArrayList(); // frames read from current file
+
+ /** Reads gif images from an URL.
+ * @param url the URL
+ * @throws IOException on error
+ */
+ public GifImage(URL url) throws IOException {
+ fromUrl = url;
+ InputStream is = null;
+ try {
+ is = url.openStream();
+ process(is);
+ }
+ finally {
+ if (is != null) {
+ is.close();
+ }
+ }
+ }
+
+ /** Reads gif images from a file.
+ * @param file the file
+ * @throws IOException on error
+ */
+ public GifImage(String file) throws IOException {
+ this(Image.toURL(file));
+ }
+
+ /** Reads gif images from a byte array.
+ * @param data the byte array
+ * @throws IOException on error
+ */
+ public GifImage(byte data[]) throws IOException {
+ fromData = data;
+ InputStream is = null;
+ try {
+ is = new ByteArrayInputStream(data);
+ process(is);
+ }
+ finally {
+ if (is != null) {
+ is.close();
+ }
+ }
+ }
+
+ /** Reads gif images from a stream. The stream is not closed.
+ * @param is the stream
+ * @throws IOException on error
+ */
+ public GifImage(InputStream is) throws IOException {
+ process(is);
+ }
+
+ /** Gets the number of frames the gif has.
+ * @return the number of frames the gif has
+ */
+ public int getFrameCount() {
+ return frames.size();
+ }
+
+ /** Gets the image from a frame. The first frame is 1.
+ * @param frame the frame to get the image from
+ * @return the image
+ */
+ public Image getImage(int frame) {
+ GifFrame gf = (GifFrame)frames.get(frame - 1);
+ return gf.image;
+ }
+
+ /** Gets the [x,y] position of the frame in reference to the
+ * logical screen.
+ * @param frame the frame
+ * @return the [x,y] position of the frame
+ */
+ public int[] getFramePosition(int frame) {
+ GifFrame gf = (GifFrame)frames.get(frame - 1);
+ return new int[]{gf.ix, gf.iy};
+
+ }
+
+ /** Gets the logical screen. The images may be smaller and placed
+ * in some position in this screen to playback some animation.
+ * No image will be be bigger that this.
+ * @return the logical screen dimensions as [x,y]
+ */
+ public int[] getLogicalScreen() {
+ return new int[]{width, height};
+ }
+
+ void process(InputStream is) throws IOException {
+ in = new DataInputStream(new BufferedInputStream(is));
+ readHeader();
+ readContents();
+ if (frames.size() == 0)
+ throw new IOException("The file does not contain any valid image.");
+ }
+
+ /**
+ * Reads GIF file header information.
+ */
+ protected void readHeader() throws IOException {
+ String id = "";
+ for (int i = 0; i < 6; i++)
+ id += (char)in.read();
+ if (!id.startsWith("GIF8")) {
+ throw new IOException("Gif signature nor found.");
+ }
+
+ readLSD();
+ if (gctFlag) {
+ m_global_table = readColorTable(m_gbpc);
+ }
+ }
+
+ /**
+ * Reads Logical Screen Descriptor
+ */
+ protected void readLSD() throws IOException {
+
+ // logical screen size
+ width = readShort();
+ height = readShort();
+
+ // packed fields
+ int packed = in.read();
+ gctFlag = (packed & 0x80) != 0; // 1 : global color table flag
+ m_gbpc = (packed & 7) + 1;
+ bgIndex = in.read(); // background color index
+ pixelAspect = in.read(); // pixel aspect ratio
+ }
+
+ /**
+ * Reads next 16-bit value, LSB first
+ */
+ protected int readShort() throws IOException {
+ // read 16-bit value, LSB first
+ return in.read() | (in.read() << 8);
+ }
+
+ /**
+ * Reads next variable length block from input.
+ *
+ * @return number of bytes stored in "buffer"
+ */
+ protected int readBlock() throws IOException {
+ blockSize = in.read();
+ if (blockSize <= 0)
+ return blockSize = 0;
+ for (int k = 0; k < blockSize; ++k) {
+ int v = in.read();
+ if (v < 0) {
+ return blockSize = k;
+ }
+ block[k] = (byte)v;
+ }
+ return blockSize;
+ }
+
+ protected byte[] readColorTable(int bpc) throws IOException {
+ int ncolors = 1 << bpc;
+ int nbytes = 3*ncolors;
+ bpc = newBpc(bpc);
+ byte table[] = new byte[(1 << bpc) * 3];
+ in.readFully(table, 0, nbytes);
+ return table;
+ }
+
+
+ static protected int newBpc(int bpc) {
+ switch (bpc) {
+ case 1:
+ case 2:
+ case 4:
+ break;
+ case 3:
+ return 4;
+ default:
+ return 8;
+ }
+ return bpc;
+ }
+
+ protected void readContents() throws IOException {
+ // read GIF file content blocks
+ boolean done = false;
+ while (!done) {
+ int code = in.read();
+ switch (code) {
+
+ case 0x2C: // image separator
+ readImage();
+ break;
+
+ case 0x21: // extension
+ code = in.read();
+ switch (code) {
+
+ case 0xf9: // graphics control extension
+ readGraphicControlExt();
+ break;
+
+ case 0xff: // application extension
+ readBlock();
+ skip(); // don't care
+ break;
+
+ default: // uninteresting extension
+ skip();
+ }
+ break;
+
+ default:
+ done = true;
+ break;
+ }
+ }
+ }
+
+ /**
+ * Reads next frame image
+ */
+ protected void readImage() throws IOException {
+ ix = readShort(); // (sub)image position & size
+ iy = readShort();
+ iw = readShort();
+ ih = readShort();
+
+ int packed = in.read();
+ 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
+ m_bpc = newBpc(m_gbpc);
+ if (lctFlag) {
+ m_curr_table = readColorTable((packed & 7) + 1); // read table
+ m_bpc = newBpc((packed & 7) + 1);
+ }
+ else {
+ m_curr_table = m_global_table;
+ }
+ if (transparency && transIndex >= m_curr_table.length / 3)
+ transparency = false;
+ if (transparency && m_bpc == 1) { // Acrobat 5.05 doesn't like this combination
+ byte tp[] = new byte[12];
+ System.arraycopy(m_curr_table, 0, tp, 0, 6);
+ m_curr_table = tp;
+ m_bpc = 2;
+ }
+ boolean skipZero = decodeImageData(); // decode pixel data
+ if (!skipZero)
+ skip();
+
+ Image img = null;
+ try {
+ img = new ImgRaw(iw, ih, 1, m_bpc, m_out);
+ PdfArray colorspace = new PdfArray();
+ colorspace.add(PdfName.INDEXED);
+ colorspace.add(PdfName.DEVICERGB);
+ int len = m_curr_table.length;
+ colorspace.add(new PdfNumber(len / 3 - 1));
+ colorspace.add(new PdfString(m_curr_table));
+ PdfDictionary ad = new PdfDictionary();
+ ad.put(PdfName.COLORSPACE, colorspace);
+ img.setAdditional(ad);
+ if (transparency) {
+ img.setTransparency(new int[]{transIndex, transIndex});
+ }
+ }
+ catch (Exception e) {
+ throw new ExceptionConverter(e);
+ }
+ img.setOriginalType(Image.ORIGINAL_GIF);
+ img.setOriginalData(fromData);
+ img.setUrl(fromUrl);
+ GifFrame gf = new GifFrame();
+ gf.image = img;
+ gf.ix = ix;
+ gf.iy = iy;
+ frames.add(gf); // add image to frame list
+
+ //resetFrame();
+
+ }
+
+ protected boolean decodeImageData() throws IOException {
+ 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;
+ boolean skipZero = false;
+
+ if (prefix == null)
+ prefix = new short[MaxStackSize];
+ if (suffix == null)
+ suffix = new byte[MaxStackSize];
+ if (pixelStack == null)
+ pixelStack = new byte[MaxStackSize+1];
+
+ m_line_stride = (iw * m_bpc + 7) / 8;
+ m_out = new byte[m_line_stride * ih];
+ int pass = 1;
+ int inc = interlace ? 8 : 1;
+ int line = 0;
+ int xpos = 0;
+
+ // Initialize GIF data stream decoder.
+
+ data_size = in.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 = 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) {
+ skipZero = true;
+ 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 code
+
+ if ((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--;
+ i++;
+
+ setPixel(xpos, line, pixelStack[top]);
+ ++xpos;
+ if (xpos >= iw) {
+ xpos = 0;
+ line += inc;
+ if (line >= ih) {
+ if (interlace) {
+ do {
+ pass++;
+ switch (pass) {
+ case 2:
+ line = 4;
+ break;
+ case 3:
+ line = 2;
+ inc = 4;
+ break;
+ case 4:
+ line = 1;
+ inc = 2;
+ break;
+ default: // this shouldn't happen
+ line = ih - 1;
+ inc = 0;
+ }
+ } while (line >= ih);
+ }
+ else {
+ line = ih - 1; // this shouldn't happen
+ inc = 0;
+ }
+ }
+ }
+ }
+ return skipZero;
+ }
+
+
+ protected void setPixel(int x, int y, int v) {
+ if (m_bpc == 8) {
+ int pos = x + iw * y;
+ m_out[pos] = (byte)v;
+ }
+ else {
+ int pos = m_line_stride * y + x / (8 / m_bpc);
+ int vout = v << (8 - m_bpc * (x % (8 / m_bpc))- m_bpc);
+ m_out[pos] |= vout;
+ }
+ }
+
+ /**
+ * Resets frame state for reading next image.
+ */
+ protected void resetFrame() {
+ // it does nothing in the pdf context
+ //boolean transparency = false;
+ //int delay = 0;
+ }
+
+ /**
+ * Reads Graphics Control Extension values
+ */
+ protected void readGraphicControlExt() throws IOException {
+ in.read(); // block size
+ int packed = in.read(); // 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 = in.read(); // transparent color index
+ in.read(); // block terminator
+ }
+
+ /**
+ * Skips variable length blocks up to and including
+ * next zero length block.
+ */
+ protected void skip() throws IOException {
+ do {
+ readBlock();
+ } while (blockSize > 0);
+ }
+
+ static class GifFrame {
+ Image image;
+ int ix;
+ int iy;
+ }
+}
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