diff options
Diffstat (limited to 'bundles/org.eclipse.swt/Eclipse SWT/common/org/eclipse/swt/internal/image/LZWCodec.java')
| -rwxr-xr-x | bundles/org.eclipse.swt/Eclipse SWT/common/org/eclipse/swt/internal/image/LZWCodec.java | 476 |
1 files changed, 0 insertions, 476 deletions
diff --git a/bundles/org.eclipse.swt/Eclipse SWT/common/org/eclipse/swt/internal/image/LZWCodec.java b/bundles/org.eclipse.swt/Eclipse SWT/common/org/eclipse/swt/internal/image/LZWCodec.java deleted file mode 100755 index 184d43f057..0000000000 --- a/bundles/org.eclipse.swt/Eclipse SWT/common/org/eclipse/swt/internal/image/LZWCodec.java +++ /dev/null @@ -1,476 +0,0 @@ -package org.eclipse.swt.internal.image;
-
-/*
- * (c) Copyright IBM Corp. 2000, 2001.
- * All Rights Reserved
- */
-
-import org.eclipse.swt.*;
-import org.eclipse.swt.graphics.*;
-
-final class LZWCodec {
- int bitsPerPixel, blockSize, blockIndex, currentByte, bitsLeft,
- codeSize, clearCode, endCode, newCodes, topSlot, currentSlot,
- imageWidth, imageHeight, imageX, imageY, pass, line, codeMask, buffer;
- byte[] block, lineArray;
- int[] maskTable, stack, suffix, prefix;
- LZWNode[] nodeStack;
- LEDataInputStream inputStream;
- LEDataOutputStream outputStream;
- ImageData image;
- ImageLoader loader;
- boolean interlaced;
-/**
- * Decode the input.
- */
-void decode() {
- int code;
- int oc = 0;
- int fc = 0;
- byte[] buf = new byte[imageWidth];
- int stackIndex = 0;
- int bufIndex = 0;
- int c;
- while ((c = nextCode()) != endCode) {
- if (c == clearCode) {
- codeSize = bitsPerPixel + 1;
- codeMask = maskTable[bitsPerPixel];
- currentSlot = newCodes;
- topSlot = 1 << codeSize;
- while ((c = nextCode()) == clearCode) {};
- if (c != endCode) {
- oc = fc = c;
- buf[bufIndex] = (byte)c;
- bufIndex++;
- if (bufIndex == imageWidth) {
- nextPutPixels(buf);
- bufIndex = 0;
- }
- }
- } else {
- code = c;
- if (code >= currentSlot) {
- if (code > currentSlot)
- SWT.error(SWT.ERROR_INVALID_IMAGE);
- code = oc;
- stack[stackIndex] = fc;
- stackIndex++;
- }
- while (code >= newCodes) {
- stack[stackIndex] = suffix[code];
- stackIndex++;
- code = prefix[code];
- }
- stack[stackIndex] = code;
- stackIndex++;
- if (currentSlot < topSlot) {
- fc = code;
- suffix[currentSlot] = fc;
- prefix[currentSlot] = oc;
- currentSlot++;
- oc = c;
- }
- if (currentSlot >= topSlot) {
- if (codeSize < 12) {
- codeMask = maskTable[codeSize];
- codeSize++;
- topSlot = topSlot + topSlot;
- }
- }
- while (stackIndex > 0) {
- stackIndex--;
- buf[bufIndex] = (byte)stack[stackIndex];
- bufIndex++;
- if (bufIndex == imageWidth) {
- nextPutPixels(buf);
- bufIndex = 0;
- }
- }
- }
- }
- if (bufIndex != 0 && line < imageHeight) {
- nextPutPixels(buf);
- }
-}
-/**
- * Decode the LZW-encoded bytes in the given byte stream
- * into the given DeviceIndependentImage.
- */
-public void decode(LEDataInputStream inputStream, ImageLoader loader, ImageData image, boolean interlaced, int depth) {
- this.inputStream = inputStream;
- this.loader = loader;
- this.image = image;
- this.interlaced = interlaced;
- this.bitsPerPixel = depth;
- initializeForDecoding();
- decode();
-}
-/**
- * Encode the image.
- */
-void encode() {
- nextPutCode(clearCode);
- int lastPrefix = encodeLoop();
- nextPutCode(lastPrefix);
- nextPutCode(endCode);
-
- // Write out last partial block
- if (bitsLeft == 8) {
- block[0] = (byte)(blockIndex - 1); // Nothing in last byte
- } else {
- block[0] = (byte)(blockIndex); // Last byte has data
- }
- writeBlock();
-
- // Write out empty block to indicate the end (if needed)
- if (block[0] != 0) {
- block[0] = 0;
- writeBlock();
- }
-}
-/**
- * Encode the bytes into the given byte stream
- * from the given DeviceIndependentImage.
- */
-public void encode(LEDataOutputStream byteStream, ImageData image) {
- this.outputStream = byteStream;
- this.image = image;
- initializeForEncoding();
- encode();
-}
-/**
- * Encoding loop broken out to allow early return.
- */
-int encodeLoop() {
- int pixel = nextPixel();
- boolean found;
- LZWNode node;
- while (true) {
- int currentPrefix = pixel;
- node = nodeStack[currentPrefix];
- found = true;
- pixel = nextPixel();
- if (pixel < 0)
- return currentPrefix;
- while (found && (node.children != null)) {
- node = node.children;
- while (found && (node.suffix != pixel)) {
- if (pixel < node.suffix) {
- if (node.left == null) {
- node.left = new LZWNode();
- found = false;
- }
- node = node.left;
- } else {
- if (node.right == null) {
- node.right = new LZWNode();
- found = false;
- }
- node = node.right;
- }
- }
- if (found) {
- currentPrefix = node.code;
- pixel = nextPixel();
- if (pixel < 0)
- return currentPrefix;
- }
- }
- if (found) {
- node.children = new LZWNode();
- node = node.children;
- }
- node.children = null;
- node.left = null;
- node.right = null;
- node.code = currentSlot;
- node.prefix = currentPrefix;
- node.suffix = pixel;
- nextPutCode(currentPrefix);
- currentSlot++;
- // Off by one?
- if (currentSlot < 4096) {
- if (currentSlot > topSlot) {
- codeSize++;
- codeMask = maskTable[codeSize - 1];
- topSlot *= 2;
- }
- } else {
- nextPutCode(clearCode);
- for (int i = 0; i < nodeStack.length; i++)
- nodeStack[i].children = null;
- codeSize = bitsPerPixel + 1;
- codeMask = maskTable[codeSize - 1];
- currentSlot = newCodes;
- topSlot = 1 << codeSize;
- }
- }
-}
-/**
- * Initialize the receiver for decoding the given
- * byte array.
- */
-void initializeForDecoding() {
- pass = 1;
- line = 0;
- codeSize = bitsPerPixel + 1;
- topSlot = 1 << codeSize;
- clearCode = 1 << bitsPerPixel;
- endCode = clearCode + 1;
- newCodes = currentSlot = endCode + 1;
- currentByte = -1;
- blockSize = bitsLeft = 0;
- blockIndex = 0;
- maskTable = new int[] {
- 0x1, 0x3, 0x7, 0xF, 0x1F, 0x3F, 0x7F,
- 0xFF, 0x1FF, 0x3FF, 0x7FF, 0xFFF
- };
- codeMask = maskTable[codeSize - 1];
- stack = new int[4096];
- suffix = new int[4096];
- prefix = new int[4096];
- block = new byte[256];
- imageWidth = image.width;
- imageHeight = image.height;
-}
-/**
- * Initialize the receiver for encoding the given
- * byte array.
- */
-void initializeForEncoding() {
- interlaced = false;
- bitsPerPixel = image.depth;
- codeSize = bitsPerPixel + 1;
- topSlot = 1 << codeSize;
- clearCode = 1 << bitsPerPixel;
- endCode = clearCode + 1;
- newCodes = currentSlot = endCode + 1;
- bitsLeft = 8;
- currentByte = 0;
- blockIndex = 1;
- blockSize = 255;
- block = new byte[blockSize];
- block[0] = (byte)(blockSize - 1);
- maskTable = new int[] {
- 0x1, 0x3, 0x7, 0xF, 0x1F, 0x3F, 0x7F,
- 0xFF, 0x1FF, 0x3FF, 0x7FF, 0xFFF
- };
- nodeStack = new LZWNode[1 << bitsPerPixel];
- for (int i = 0; i < nodeStack.length; i++) {
- LZWNode node = new LZWNode();
- node.code = i + 1;
- node.prefix = -1;
- node.suffix = i + 1;
- nodeStack[i] = node;
- }
- imageWidth = image.width;
- imageHeight = image.height;
- imageY = -1;
- lineArray = new byte[imageWidth];
- imageX = imageWidth + 1; // Force a read
-}
-/**
- * Answer the next code from the input byte array.
- */
-int nextCode() {
- int code;
- if (bitsLeft == 0) {
- if (blockIndex >= blockSize) {
- blockSize = readBlock();
- blockIndex = 0;
- if (blockSize == 0) return endCode;
- }
- blockIndex++;
- currentByte = block[blockIndex] & 0xFF;
- bitsLeft = 8;
- code = currentByte;
- } else {
- int shift = bitsLeft - 8;
- if (shift < 0)
- code = currentByte >> (0 - shift);
- else
- code = currentByte << shift;
- }
- while (codeSize > bitsLeft) {
- if (blockIndex >= blockSize) {
- blockSize = readBlock();
- blockIndex = 0;
- if (blockSize == 0) return endCode;
- }
- blockIndex++;
- currentByte = block[blockIndex] & 0xFF;
- code += currentByte << bitsLeft;
- bitsLeft += 8;
- }
- bitsLeft -= codeSize;
- return code & codeMask;
-}
-/**
- * Answer the next pixel to encode in the image
- */
-int nextPixel() {
- imageX++;
- if (imageX > imageWidth) {
- imageY++;
- if (imageY >= imageHeight) {
- return -1;
- } else {
- nextPixels(lineArray, imageWidth);
- }
- imageX = 1;
- }
- return this.lineArray[imageX - 1] & 0xFF;
-}
-/**
- * Copy a row of pixel values from the image.
- */
-void nextPixels(byte[] buf, int lineWidth) {
- if (image.depth == 8) {
- System.arraycopy(image.data, imageY * image.bytesPerLine, buf, 0, lineWidth);
- } else {
- image.getPixels(0, imageY, lineWidth, buf, 0);
- }
-}
-/**
- * Output aCode to the output stream.
- */
-void nextPutCode(int aCode) {
- int codeToDo = aCode;
- int codeBitsToDo = codeSize;
- // Fill in the remainder of the current byte with the
- // *high-order* bits of the code.
- int c = codeToDo & maskTable[bitsLeft - 1];
- currentByte = currentByte | (c << (8 - bitsLeft));
- block[blockIndex] = (byte)currentByte;
- codeBitsToDo -= bitsLeft;
- if (codeBitsToDo < 1) {
- // The whole code fit in the first byte, so we are done.
- bitsLeft -= codeSize;
- if (bitsLeft == 0) {
- // We used the whole last byte, so get ready
- // for the next one.
- bitsLeft = 8;
- blockIndex++;
- if (blockIndex >= blockSize) {
- writeBlock();
- blockIndex = 1;
- }
- currentByte = 0;
- }
- return;
- }
- codeToDo = codeToDo >> bitsLeft;
-
- // Fill in any remaining whole bytes (i.e. not the last one!)
- blockIndex++;
- if (blockIndex >= blockSize) {
- writeBlock();
- blockIndex = 1;
- }
- while (codeBitsToDo >= 8) {
- currentByte = codeToDo & 0xFF;
- block[blockIndex] = (byte)currentByte;
- codeToDo = codeToDo >> 8;
- codeBitsToDo -= 8;
- blockIndex++;
- if (blockIndex >= blockSize) {
- writeBlock();
- blockIndex = 1;
- }
- }
- // Fill the *low-order* bits of the last byte with the remainder
- bitsLeft = 8 - codeBitsToDo;
- currentByte = codeToDo;
- block[blockIndex] = (byte)currentByte;
-}
-/**
- * Copy a row of pixel values to the image.
- */
-void nextPutPixels(byte[] buf) {
- if (image.depth == 8) {
- // Slight optimization for depth = 8.
- int start = line * image.bytesPerLine;
- for (int i = 0; i < imageWidth; i++)
- image.data[start + i] = buf[i];
- } else {
- image.setPixels(0, line, imageWidth, buf, 0);
- }
- if (interlaced) {
- if (pass == 1) {
- copyRow(buf, 7);
- line += 8;
- } else if (pass == 2) {
- copyRow(buf, 3);
- line += 8;
- } else if (pass == 3) {
- copyRow(buf, 1);
- line += 4;
- } else if (pass == 4) {
- line += 2;
- } else if (pass == 5) {
- line += 0;
- }
- if (line >= imageHeight) {
- pass++;
- if (pass == 2) line = 4;
- else if (pass == 3) line = 2;
- else if (pass == 4) line = 1;
- else if (pass == 5) line = 0;
- if (pass < 5) {
- if (loader.hasListeners()) {
- ImageData imageCopy = (ImageData) image.clone();
- loader.notifyListeners(
- new ImageLoaderEvent(loader, imageCopy, pass - 2, false));
- }
- }
- }
- if (line >= imageHeight) line = 0;
- } else {
- line++;
- }
-}
-/**
- * Copy duplicate rows of pixel values to the image.
- * This is to fill in rows if the image is interlaced.
- */
-void copyRow(byte[] buf, int copies) {
- for (int i = 1; i <= copies; i++) {
- if (line + i < imageHeight) {
- image.setPixels(0, line + i, imageWidth, buf, 0);
- }
- }
-}
-/**
- * Read a block from the byte stream.
- * Return the number of bytes read.
- * Throw an exception if the block could not be read.
- */
-int readBlock() {
- int size = -1;
- try {
- size = inputStream.read();
- if (size == -1) {
- SWT.error(SWT.ERROR_INVALID_IMAGE);
- }
- block[0] = (byte)size;
- size = inputStream.read(block, 1, size);
- if (size == -1) {
- SWT.error(SWT.ERROR_INVALID_IMAGE);
- }
- } catch (Exception e) {
- SWT.error(SWT.ERROR_IO, e);
- }
- return size;
-}
-/**
- * Write a block to the byte stream.
- * Throw an exception if the block could not be written.
- */
-void writeBlock() {
- try {
- outputStream.write(block, 0, (block[0] & 0xFF) + 1);
- } catch (Exception e) {
- SWT.error(SWT.ERROR_IO, e);
- }
-}
-}
|