bundles/org.eclipse.swt/Eclipse SWT/common/org/eclipse/swt/internal/image/PngEncoder.java - platform/eclipse.platform.swt - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2011 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.swt.internal.image;

 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.OutputStream;

 import org.eclipse.swt.SWT;
 import org.eclipse.swt.graphics.ImageData;
 import org.eclipse.swt.graphics.ImageLoader;
 import org.eclipse.swt.graphics.RGB;
 import org.eclipse.swt.internal.Compatibility;

 final class PngEncoder extends Object {

 	static final byte SIGNATURE[] = {(byte) '\211', (byte) 'P', (byte) 'N', (byte) 'G', (byte) '\r', (byte) '\n', (byte) '\032', (byte) '\n'};
 	static final byte TAG_IHDR[] = {(byte) 'I', (byte) 'H', (byte) 'D', (byte) 'R'};
 	static final byte TAG_PLTE[] = {(byte) 'P', (byte) 'L', (byte) 'T', (byte) 'E'};
 	static final byte TAG_TRNS[] = {(byte) 't', (byte) 'R', (byte) 'N', (byte) 'S'};
 	static final byte TAG_IDAT[] = {(byte) 'I', (byte) 'D', (byte) 'A', (byte) 'T'};
 	static final byte TAG_IEND[] = {(byte) 'I', (byte) 'E', (byte) 'N', (byte) 'D'};

 	static final int NO_COMPRESSION = 0;
 	static final int BEST_SPEED = 1;
 	static final int BEST_COMPRESSION = 9;
 	static final int DEFAULT_COMPRESSION = -1;

 	ByteArrayOutputStream bytes = new ByteArrayOutputStream(1024);
 	PngChunk chunk;

 	ImageLoader loader;
 	ImageData data;
 	int transparencyType;

 	int width, height, bitDepth, colorType;

 	int compressionMethod = 0;
 	int filterMethod = 0;
 	int interlaceMethod = 0;

 public PngEncoder(ImageLoader loader) {

 	this.loader = loader;
 	this.data = loader.data[0];
 	this.transparencyType = data.getTransparencyType();

 	this.width = data.width;
 	this.height = data.height;

 	this.bitDepth = 8;

 	this.colorType = 2;

 	if (data.palette.isDirect) {
 		if (transparencyType == SWT.TRANSPARENCY_ALPHA) {
 			this.colorType = 6;
 		}
 	}
 	else {
 		this.colorType = 3;
 	}

 	if (!(colorType == 2 || colorType == 3 || colorType == 6)) SWT.error(SWT.ERROR_INVALID_IMAGE);

 }

 void writeShort(ByteArrayOutputStream baos, int theShort) {

 	byte byte1 = (byte) ((theShort >> 8) & 0xff);
 	byte byte2 = (byte) (theShort & 0xff);
 	byte[] temp = {byte1, byte2};
 	baos.write(temp, 0, 2);

 }

 void writeInt(ByteArrayOutputStream baos, int theInt) {

 	byte byte1 = (byte) ((theInt >> 24) & 0xff);
 	byte byte2 = (byte) ((theInt >> 16) & 0xff);
 	byte byte3 = (byte) ((theInt >> 8) & 0xff);
 	byte byte4 = (byte) (theInt & 0xff);
 	byte[] temp = {byte1, byte2, byte3, byte4};
 	baos.write(temp, 0, 4);

 }

 void writeChunk(byte[] tag, byte[] buffer) {

 	int bufferLength = (buffer != null) ? buffer.length : 0;

 	chunk = new PngChunk(bufferLength);

 	writeInt(bytes, bufferLength);
 	bytes.write(tag, 0, 4);
 	chunk.setType(tag);
 	if (bufferLength != 0) {
 		bytes.write(buffer, 0, bufferLength);
 		chunk.setData(buffer);
 	}
 	else {
 		chunk.setCRC(chunk.computeCRC());
 	}
 	writeInt(bytes, chunk.getCRC());

 }

 void writeSignature() {

 	bytes.write(SIGNATURE, 0, 8);

 }

 void writeHeader() {

 	ByteArrayOutputStream baos = new ByteArrayOutputStream(13);

 	writeInt(baos, width);
 	writeInt(baos, height);
 	baos.write(bitDepth);
 	baos.write(colorType);
 	baos.write(compressionMethod);
 	baos.write(filterMethod);
 	baos.write(interlaceMethod);

 	writeChunk(TAG_IHDR, baos.toByteArray());

 }

 void writePalette() {

 	RGB[] RGBs = data.palette.getRGBs();

 	if (RGBs.length > 256) SWT.error(SWT.ERROR_INVALID_IMAGE);

 	ByteArrayOutputStream baos = new ByteArrayOutputStream(RGBs.length);

 	for (int i = 0; i < RGBs.length; i++) {

 		baos.write((byte) RGBs[i].red);
 		baos.write((byte) RGBs[i].green);
 		baos.write((byte) RGBs[i].blue);

 	}

 	writeChunk(TAG_PLTE, baos.toByteArray());

 }

 void writeTransparency() {

 	ByteArrayOutputStream baos = new ByteArrayOutputStream();

 	switch (transparencyType) {

 		case SWT.TRANSPARENCY_ALPHA:

 			int pixelValue, alphaValue;

 			byte[] alphas = new byte[data.palette.getRGBs().length];

 			for (int y = 0; y < height; y++) {

 				for (int x = 0; x < width; x++) {

 					pixelValue = data.getPixel(x, y);
 					alphaValue = data.getAlpha(x, y);

 					alphas[pixelValue] = (byte) alphaValue;

 				}

 			}

 			baos.write(alphas, 0, alphas.length);

 			break;

 		case SWT.TRANSPARENCY_PIXEL:

 			int pixel = data.transparentPixel;

 			if (colorType == 2) {

 				int redMask = data.palette.redMask;
 				int redShift = data.palette.redShift;
 				int greenMask = data.palette.greenMask;
 				int greenShift = data.palette.greenShift;
 				int blueShift = data.palette.blueShift;
 				int blueMask = data.palette.blueMask;

 				int r = pixel & redMask;
 				r = (redShift < 0) ? r >>> -redShift : r << redShift;
 				int g = pixel & greenMask;
 				g = (greenShift < 0) ? g >>> -greenShift : g << greenShift;
 				int b = pixel & blueMask;
 				b = (blueShift < 0) ? b >>> -blueShift : b << blueShift;

 				writeShort(baos, r);
 				writeShort(baos, g);
 				writeShort(baos, b);

 			}

 			if (colorType == 3) {

 				byte[] padding = new byte[pixel + 1];

 				for (int i = 0; i < pixel; i++) {

 					padding[i] = (byte) 255;

 				}

 				padding[pixel] = (byte) 0;

 				baos.write(padding, 0, padding.length);

 			}

 			break;

 	}

 	writeChunk(TAG_TRNS, baos.toByteArray());

 }

 void writeImageData() throws IOException {

 	ByteArrayOutputStream baos = new ByteArrayOutputStream(1024);
 	OutputStream os = null;
 	switch (loader.compression) {
 	case 0:
 		os = Compatibility.newDeflaterOutputStream(baos, NO_COMPRESSION);
 		break;
 	case 1:
 		os = Compatibility.newDeflaterOutputStream(baos, BEST_SPEED);
 		break;
 	case 3:
 		os = Compatibility.newDeflaterOutputStream(baos, BEST_COMPRESSION);
 		break;
 	default:
 		os = Compatibility.newDeflaterOutputStream(baos, DEFAULT_COMPRESSION);
 		break;
 	}
 	if (os == null) os = baos; // returns null for J2ME

 	if (colorType == 3) {

 		byte[] lineData = new byte[width];

 		for (int y = 0; y < height; y++) {

 			int filter = 0;
 			os.write(filter);

 			data.getPixels(0, y, width, lineData, 0);

 			os.write(lineData);

 		}

 	}

 	else {

 		int[] lineData = new int[width];
 		byte[] alphaData = null;
 		if (colorType == 6) {
 			alphaData = new byte[width];
 		}

 		int redMask = data.palette.redMask;
 		int redShift = data.palette.redShift;
 		int greenMask = data.palette.greenMask;
 		int greenShift = data.palette.greenShift;
 		int blueShift = data.palette.blueShift;
 		int blueMask = data.palette.blueMask;

 		byte[] lineBytes = new byte[width * (colorType == 6 ? 4 : 3)];

 		for (int y = 0; y < height; y++) {

 			int filter = 0;
 			os.write(filter);

 			data.getPixels(0, y, width, lineData, 0);

 			if (colorType == 6) {
 				data.getAlphas(0, y, width, alphaData, 0);
 			}

 			int offset = 0;
 			for (int x = 0; x < lineData.length; x++) {

 				int pixel = lineData[x];

 				int r = pixel & redMask;
 				lineBytes[offset++] = (byte) ((redShift < 0) ? r >>> -redShift
 						: r << redShift);
 				int g = pixel & greenMask;
 				lineBytes[offset++] = (byte) ((greenShift < 0) ? g >>> -greenShift
 						: g << greenShift);
 				int b = pixel & blueMask;
 				lineBytes[offset++] = (byte) ((blueShift < 0) ? b >>> -blueShift
 						: b << blueShift);

 				if (colorType == 6) {
 					lineBytes[offset++] = alphaData[x];
 				}

 			}

 			os.write(lineBytes);

 		}

 	}

 	os.flush();
 	os.close();

 	byte[] compressed = baos.toByteArray();
 	if (os == baos) {
 		/* Use PngDeflater for J2ME. */
 		PngDeflater deflater = new PngDeflater();
 		compressed = deflater.deflate(compressed);
 	}

 	writeChunk(TAG_IDAT, compressed);

 }

 void writeEnd() {

 	writeChunk(TAG_IEND, null);

 }

 public void encode(LEDataOutputStream outputStream) {

 	try {

 		writeSignature();
 		writeHeader();

 		if (colorType == 3) {
 			writePalette();
 		}

 		boolean transparencyAlpha = (transparencyType == SWT.TRANSPARENCY_ALPHA);
 		boolean transparencyPixel = (transparencyType == SWT.TRANSPARENCY_PIXEL);
 		boolean type2Transparency = (colorType == 2 && transparencyPixel);
 		boolean type3Transparency = (colorType == 3 && (transparencyAlpha || transparencyPixel));

 		if (type2Transparency || type3Transparency) {
 			writeTransparency();
 		}

 		writeImageData();
 		writeEnd();

 		outputStream.write(bytes.toByteArray());

 	}

 	catch (IOException e) {

 		SWT.error(SWT.ERROR_IO, e);

 	}

 }

 }
	/*******************************************************************************
	* Copyright (c) 2000, 2011 IBM Corporation and others.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License v1.0
	* which accompanies this distribution, and is available at
	* http://www.eclipse.org/legal/epl-v10.html
	*
	* Contributors:
	* IBM Corporation - initial API and implementation
	*******************************************************************************/
	package org.eclipse.swt.internal.image;

	import java.io.ByteArrayOutputStream;
	import java.io.IOException;
	import java.io.OutputStream;

	import org.eclipse.swt.SWT;
	import org.eclipse.swt.graphics.ImageData;
	import org.eclipse.swt.graphics.ImageLoader;
	import org.eclipse.swt.graphics.RGB;
	import org.eclipse.swt.internal.Compatibility;

	final class PngEncoder extends Object {

	static final byte SIGNATURE[] = {(byte) '\211', (byte) 'P', (byte) 'N', (byte) 'G', (byte) '\r', (byte) '\n', (byte) '\032', (byte) '\n'};
	static final byte TAG_IHDR[] = {(byte) 'I', (byte) 'H', (byte) 'D', (byte) 'R'};
	static final byte TAG_PLTE[] = {(byte) 'P', (byte) 'L', (byte) 'T', (byte) 'E'};
	static final byte TAG_TRNS[] = {(byte) 't', (byte) 'R', (byte) 'N', (byte) 'S'};
	static final byte TAG_IDAT[] = {(byte) 'I', (byte) 'D', (byte) 'A', (byte) 'T'};
	static final byte TAG_IEND[] = {(byte) 'I', (byte) 'E', (byte) 'N', (byte) 'D'};

	static final int NO_COMPRESSION = 0;
	static final int BEST_SPEED = 1;
	static final int BEST_COMPRESSION = 9;
	static final int DEFAULT_COMPRESSION = -1;

	ByteArrayOutputStream bytes = new ByteArrayOutputStream(1024);
	PngChunk chunk;

	ImageLoader loader;
	ImageData data;
	int transparencyType;

	int width, height, bitDepth, colorType;

	int compressionMethod = 0;
	int filterMethod = 0;
	int interlaceMethod = 0;

	public PngEncoder(ImageLoader loader) {

	this.loader = loader;
	this.data = loader.data[0];
	this.transparencyType = data.getTransparencyType();

	this.width = data.width;
	this.height = data.height;

	this.bitDepth = 8;

	this.colorType = 2;

	if (data.palette.isDirect) {
	if (transparencyType == SWT.TRANSPARENCY_ALPHA) {
	this.colorType = 6;
	}
	}
	else {
	this.colorType = 3;
	}

	if (!(colorType == 2 \|\| colorType == 3 \|\| colorType == 6)) SWT.error(SWT.ERROR_INVALID_IMAGE);

	}

	void writeShort(ByteArrayOutputStream baos, int theShort) {

	byte byte1 = (byte) ((theShort >> 8) & 0xff);
	byte byte2 = (byte) (theShort & 0xff);
	byte[] temp = {byte1, byte2};
	baos.write(temp, 0, 2);

	}

	void writeInt(ByteArrayOutputStream baos, int theInt) {

	byte byte1 = (byte) ((theInt >> 24) & 0xff);
	byte byte2 = (byte) ((theInt >> 16) & 0xff);
	byte byte3 = (byte) ((theInt >> 8) & 0xff);
	byte byte4 = (byte) (theInt & 0xff);
	byte[] temp = {byte1, byte2, byte3, byte4};
	baos.write(temp, 0, 4);

	}

	void writeChunk(byte[] tag, byte[] buffer) {

	int bufferLength = (buffer != null) ? buffer.length : 0;

	chunk = new PngChunk(bufferLength);

	writeInt(bytes, bufferLength);
	bytes.write(tag, 0, 4);
	chunk.setType(tag);
	if (bufferLength != 0) {
	bytes.write(buffer, 0, bufferLength);
	chunk.setData(buffer);
	}
	else {
	chunk.setCRC(chunk.computeCRC());
	}
	writeInt(bytes, chunk.getCRC());

	}

	void writeSignature() {

	bytes.write(SIGNATURE, 0, 8);

	}

	void writeHeader() {

	ByteArrayOutputStream baos = new ByteArrayOutputStream(13);

	writeInt(baos, width);
	writeInt(baos, height);
	baos.write(bitDepth);
	baos.write(colorType);
	baos.write(compressionMethod);
	baos.write(filterMethod);
	baos.write(interlaceMethod);

	writeChunk(TAG_IHDR, baos.toByteArray());

	}

	void writePalette() {

	RGB[] RGBs = data.palette.getRGBs();

	if (RGBs.length > 256) SWT.error(SWT.ERROR_INVALID_IMAGE);

	ByteArrayOutputStream baos = new ByteArrayOutputStream(RGBs.length);

	for (int i = 0; i < RGBs.length; i++) {

	baos.write((byte) RGBs[i].red);
	baos.write((byte) RGBs[i].green);
	baos.write((byte) RGBs[i].blue);

	}

	writeChunk(TAG_PLTE, baos.toByteArray());

	}

	void writeTransparency() {

	ByteArrayOutputStream baos = new ByteArrayOutputStream();

	switch (transparencyType) {

	case SWT.TRANSPARENCY_ALPHA:

	int pixelValue, alphaValue;

	byte[] alphas = new byte[data.palette.getRGBs().length];

	for (int y = 0; y < height; y++) {

	for (int x = 0; x < width; x++) {

	pixelValue = data.getPixel(x, y);
	alphaValue = data.getAlpha(x, y);

	alphas[pixelValue] = (byte) alphaValue;

	}

	}

	baos.write(alphas, 0, alphas.length);

	break;

	case SWT.TRANSPARENCY_PIXEL:

	int pixel = data.transparentPixel;

	if (colorType == 2) {

	int redMask = data.palette.redMask;
	int redShift = data.palette.redShift;
	int greenMask = data.palette.greenMask;
	int greenShift = data.palette.greenShift;
	int blueShift = data.palette.blueShift;
	int blueMask = data.palette.blueMask;

	int r = pixel & redMask;
	r = (redShift < 0) ? r >>> -redShift : r << redShift;
	int g = pixel & greenMask;
	g = (greenShift < 0) ? g >>> -greenShift : g << greenShift;
	int b = pixel & blueMask;
	b = (blueShift < 0) ? b >>> -blueShift : b << blueShift;

	writeShort(baos, r);
	writeShort(baos, g);
	writeShort(baos, b);

	}

	if (colorType == 3) {

	byte[] padding = new byte[pixel + 1];

	for (int i = 0; i < pixel; i++) {

	padding[i] = (byte) 255;

	}

	padding[pixel] = (byte) 0;

	baos.write(padding, 0, padding.length);

	}

	break;

	}

	writeChunk(TAG_TRNS, baos.toByteArray());

	}

	void writeImageData() throws IOException {

	ByteArrayOutputStream baos = new ByteArrayOutputStream(1024);
	OutputStream os = null;
	switch (loader.compression) {
	case 0:
	os = Compatibility.newDeflaterOutputStream(baos, NO_COMPRESSION);
	break;
	case 1:
	os = Compatibility.newDeflaterOutputStream(baos, BEST_SPEED);
	break;
	case 3:
	os = Compatibility.newDeflaterOutputStream(baos, BEST_COMPRESSION);
	break;
	default:
	os = Compatibility.newDeflaterOutputStream(baos, DEFAULT_COMPRESSION);
	break;
	}
	if (os == null) os = baos; // returns null for J2ME

	if (colorType == 3) {

	byte[] lineData = new byte[width];

	for (int y = 0; y < height; y++) {

	int filter = 0;
	os.write(filter);

	data.getPixels(0, y, width, lineData, 0);

	os.write(lineData);

	}

	}

	else {

	int[] lineData = new int[width];
	byte[] alphaData = null;
	if (colorType == 6) {
	alphaData = new byte[width];
	}

	int redMask = data.palette.redMask;
	int redShift = data.palette.redShift;
	int greenMask = data.palette.greenMask;
	int greenShift = data.palette.greenShift;
	int blueShift = data.palette.blueShift;
	int blueMask = data.palette.blueMask;

	byte[] lineBytes = new byte[width * (colorType == 6 ? 4 : 3)];

	for (int y = 0; y < height; y++) {

	int filter = 0;
	os.write(filter);

	data.getPixels(0, y, width, lineData, 0);

	if (colorType == 6) {
	data.getAlphas(0, y, width, alphaData, 0);
	}

	int offset = 0;
	for (int x = 0; x < lineData.length; x++) {

	int pixel = lineData[x];

	int r = pixel & redMask;
	lineBytes[offset++] = (byte) ((redShift < 0) ? r >>> -redShift
	: r << redShift);
	int g = pixel & greenMask;
	lineBytes[offset++] = (byte) ((greenShift < 0) ? g >>> -greenShift
	: g << greenShift);
	int b = pixel & blueMask;
	lineBytes[offset++] = (byte) ((blueShift < 0) ? b >>> -blueShift
	: b << blueShift);

	if (colorType == 6) {
	lineBytes[offset++] = alphaData[x];
	}

	}

	os.write(lineBytes);

	}

	}

	os.flush();
	os.close();

	byte[] compressed = baos.toByteArray();
	if (os == baos) {
	/* Use PngDeflater for J2ME. */
	PngDeflater deflater = new PngDeflater();
	compressed = deflater.deflate(compressed);
	}

	writeChunk(TAG_IDAT, compressed);

	}

	void writeEnd() {

	writeChunk(TAG_IEND, null);

	}

	public void encode(LEDataOutputStream outputStream) {

	try {

	writeSignature();
	writeHeader();

	if (colorType == 3) {
	writePalette();
	}

	boolean transparencyAlpha = (transparencyType == SWT.TRANSPARENCY_ALPHA);
	boolean transparencyPixel = (transparencyType == SWT.TRANSPARENCY_PIXEL);
	boolean type2Transparency = (colorType == 2 && transparencyPixel);
	boolean type3Transparency = (colorType == 3 && (transparencyAlpha \|\| transparencyPixel));

	if (type2Transparency \|\| type3Transparency) {
	writeTransparency();
	}

	writeImageData();
	writeEnd();

	outputStream.write(bytes.toByteArray());

	}

	catch (IOException e) {

	SWT.error(SWT.ERROR_IO, e);

	}

	}

	}