awt/org/apache/harmony/awt/gl/image/PngDecoder.java - platform/frameworks/base - Git at Google

 /*
  *  Licensed to the Apache Software Foundation (ASF) under one or more
  *  contributor license agreements.  See the NOTICE file distributed with
  *  this work for additional information regarding copyright ownership.
  *  The ASF licenses this file to You under the Apache License, Version 2.0
  *  (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.apache.org/licenses/LICENSE-2.0
  *
  *  Unless required by applicable law or agreed to in writing, software
  *  distributed under the License is distributed on an "AS IS" BASIS,
  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  *  See the License for the specific language governing permissions and
  *  limitations under the License.
  */
 /**
  * @author Oleg V. Khaschansky
  * @version $Revision$
  *
  * @date: Jul 22, 2005
  */

 package org.apache.harmony.awt.gl.image;

 import java.io.IOException;
 import java.io.InputStream;
 import java.util.Hashtable;
 import java.awt.color.ColorSpace;
 import java.awt.image.*;
 import java.awt.*;

 import org.apache.harmony.awt.internal.nls.Messages;

 public class PngDecoder extends ImageDecoder {
     // initializes proper field IDs
     private static native void initIDs();

     static {
         System.loadLibrary("gl"); //$NON-NLS-1$
         initIDs();
     }

     private static final int hintflags =
             ImageConsumer.SINGLEFRAME | // PNG is a static image
             ImageConsumer.TOPDOWNLEFTRIGHT | // This order is only one possible
             ImageConsumer.COMPLETESCANLINES; // Don't deliver incomplete scanlines

     // Each pixel is a grayscale sample.
     private static final int PNG_COLOR_TYPE_GRAY = 0;
     // Each pixel is an R,G,B triple.
     private static final int PNG_COLOR_TYPE_RGB = 2;
     // Each pixel is a palette index, a PLTE chunk must appear.
     private static final int PNG_COLOR_TYPE_PLTE = 3;
     // Each pixel is a grayscale sample, followed by an alpha sample.
     private static final int PNG_COLOR_TYPE_GRAY_ALPHA = 4;
     // Each pixel is an R,G,B triple, followed by an alpha sample.
     private static final int PNG_COLOR_TYPE_RGBA = 6;

     private static final int INPUT_BUFFER_SIZE = 4096;
     private byte buffer[] = new byte[INPUT_BUFFER_SIZE];

     // Buffers for decoded image data
     byte byteOut[];
     int intOut[];

     // Native pointer to png decoder data
     private long hNativeDecoder;

     int imageWidth, imageHeight;
     int colorType;
     int bitDepth;
     byte cmap[];

     boolean transferInts; // Is transfer type int?.. or byte?
     int dataElementsPerPixel = 1;

     ColorModel cm;

     int updateFromScanline; // First scanline to update
     int numScanlines; // Number of scanlines to update

     private native long decode(byte[] input, int bytesInBuffer, long hDecoder);

     private static native void releaseNativeDecoder(long hDecoder);

     public PngDecoder(DecodingImageSource src, InputStream is) {
         super(src, is);
     }

     @Override
     public void decodeImage() throws IOException {
         try {
             int bytesRead = 0;
             int needBytes, offset, bytesInBuffer = 0;
             // Read from the input stream
             for (;;) {
                 needBytes = INPUT_BUFFER_SIZE - bytesInBuffer;
                 offset = bytesInBuffer;

                 bytesRead = inputStream.read(buffer, offset, needBytes);

                 if (bytesRead < 0) { // Break, nothing to read from buffer, image truncated?
                     releaseNativeDecoder(hNativeDecoder);
                     break;
                 }

                 // Keep track on how much bytes left in buffer
                 bytesInBuffer += bytesRead;
                 hNativeDecoder = decode(buffer, bytesInBuffer, hNativeDecoder);
                 // PNG decoder always consumes all bytes at once
                 bytesInBuffer = 0;

                 // if (bytesConsumed < 0)
                 //break; // Error exit

                 returnData();

                 // OK, we decoded all the picture in the right way...
                 if (hNativeDecoder == 0) {
                     break;
                 }
             }

             imageComplete(ImageConsumer.STATICIMAGEDONE);
         } catch (IOException e) {
             throw e;
         } catch (RuntimeException e) {
             imageComplete(ImageConsumer.IMAGEERROR);
             throw e;
         } finally {
             closeStream();
         }
     }

     @SuppressWarnings("unused")
     private void returnHeader() { // Called from native code
         setDimensions(imageWidth, imageHeight);

         switch (colorType) {
             case PNG_COLOR_TYPE_GRAY: {
                 if (bitDepth != 8 && bitDepth != 4 && bitDepth != 2 && bitDepth != 1) {
                     // awt.3C=Unknown PNG color type
                     throw new IllegalArgumentException(Messages.getString("awt.3C")); //$NON-NLS-1$
                 }

                 // Create gray color model
                 int numEntries = 1 << bitDepth;
                 int scaleFactor = 255 / (numEntries-1);
                 byte comps[] = new byte[numEntries];
                 for (int i = 0; i < numEntries; i++) {
                     comps[i] = (byte) (i * scaleFactor);
                 }
                 cm = new IndexColorModel(/*bitDepth*/8, numEntries, comps, comps, comps);

                 transferInts = false;
                 break;
             }

             case PNG_COLOR_TYPE_RGB: {
                 if (bitDepth != 8) {
                     // awt.3C=Unknown PNG color type
                     throw new IllegalArgumentException(Messages.getString("awt.3C")); //$NON-NLS-1$
                 }

                 cm = new DirectColorModel(24, 0xFF0000, 0xFF00, 0xFF);

                 transferInts = true;
                 break;
             }

             case PNG_COLOR_TYPE_PLTE: {
                 if (bitDepth != 8 && bitDepth != 4 && bitDepth != 2 && bitDepth != 1) {
                     // awt.3C=Unknown PNG color type
                     throw new IllegalArgumentException(Messages.getString("awt.3C")); //$NON-NLS-1$
                 }

                 cm = new IndexColorModel(/*bitDepth*/8, cmap.length / 3, cmap, 0, false);

                 transferInts = false;
                 break;
             }

             case PNG_COLOR_TYPE_GRAY_ALPHA: {
                 if (bitDepth != 8) {
                     // awt.3C=Unknown PNG color type
                     throw new IllegalArgumentException(Messages.getString("awt.3C")); //$NON-NLS-1$
                 }

                 cm = new ComponentColorModel(ColorSpace.getInstance(ColorSpace.CS_GRAY),
                         true, false,
                         Transparency.TRANSLUCENT,
                         DataBuffer.TYPE_BYTE);

                 transferInts = false;
                 dataElementsPerPixel = 2;
                 break;
             }

             case PNG_COLOR_TYPE_RGBA: {
                 if (bitDepth != 8) {
                     // awt.3C=Unknown PNG color type
                     throw new IllegalArgumentException(Messages.getString("awt.3C")); //$NON-NLS-1$
                 }

                 cm = ColorModel.getRGBdefault();

                 transferInts = true;
                 break;
             }
             default:
                 // awt.3C=Unknown PNG color type
                 throw new IllegalArgumentException(Messages.getString("awt.3C")); //$NON-NLS-1$
         }

         // Create output buffer
         if (transferInts) {
             intOut = new int[imageWidth * imageHeight];
         } else {
             byteOut = new byte[imageWidth * imageHeight * dataElementsPerPixel];
         }

         setColorModel(cm);

         setHints(hintflags);
         setProperties(new Hashtable<Object, Object>()); // Empty
     }

     // Send the data to the consumer
     private void returnData() {
         // Send 1 or more scanlines to the consumer.
         if (numScanlines > 0) {
             // Native decoder could have returned
             // some data from the next pass, handle it here
             int pass1, pass2;
             if (updateFromScanline + numScanlines > imageHeight) {
                 pass1 = imageHeight - updateFromScanline;
                 pass2 = updateFromScanline + numScanlines - imageHeight;
             } else {
                 pass1 = numScanlines;
                 pass2 = 0;
             }

             transfer(updateFromScanline, pass1);
             if (pass2 != 0) {
                 transfer(0, pass2);
             }
         }
     }

     private void transfer(int updateFromScanline, int numScanlines) {
         if (transferInts) {
             setPixels(
                     0, updateFromScanline,
                     imageWidth, numScanlines,
                     cm, intOut,
                     updateFromScanline * imageWidth,
                     imageWidth
             );
         } else {
             setPixels(
                     0, updateFromScanline,
                     imageWidth, numScanlines,
                     cm, byteOut,
                     updateFromScanline * imageWidth * dataElementsPerPixel,
                     imageWidth * dataElementsPerPixel
             );
         }
     }
 }
	/*
	* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. See the NOTICE file distributed with
	* this work for additional information regarding copyright ownership.
	* The ASF licenses this file to You under the Apache License, Version 2.0
	* (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.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/
	/**
	* @author Oleg V. Khaschansky
	* @version $Revision$
	*
	* @date: Jul 22, 2005
	*/

	package org.apache.harmony.awt.gl.image;

	import java.io.IOException;
	import java.io.InputStream;
	import java.util.Hashtable;
	import java.awt.color.ColorSpace;
	import java.awt.image.*;
	import java.awt.*;

	import org.apache.harmony.awt.internal.nls.Messages;

	public class PngDecoder extends ImageDecoder {
	// initializes proper field IDs
	private static native void initIDs();

	static {
	System.loadLibrary("gl"); //$NON-NLS-1$
	initIDs();
	}

	private static final int hintflags =
	ImageConsumer.SINGLEFRAME \| // PNG is a static image
	ImageConsumer.TOPDOWNLEFTRIGHT \| // This order is only one possible
	ImageConsumer.COMPLETESCANLINES; // Don't deliver incomplete scanlines

	// Each pixel is a grayscale sample.
	private static final int PNG_COLOR_TYPE_GRAY = 0;
	// Each pixel is an R,G,B triple.
	private static final int PNG_COLOR_TYPE_RGB = 2;
	// Each pixel is a palette index, a PLTE chunk must appear.
	private static final int PNG_COLOR_TYPE_PLTE = 3;
	// Each pixel is a grayscale sample, followed by an alpha sample.
	private static final int PNG_COLOR_TYPE_GRAY_ALPHA = 4;
	// Each pixel is an R,G,B triple, followed by an alpha sample.
	private static final int PNG_COLOR_TYPE_RGBA = 6;

	private static final int INPUT_BUFFER_SIZE = 4096;
	private byte buffer[] = new byte[INPUT_BUFFER_SIZE];

	// Buffers for decoded image data
	byte byteOut[];
	int intOut[];

	// Native pointer to png decoder data
	private long hNativeDecoder;

	int imageWidth, imageHeight;
	int colorType;
	int bitDepth;
	byte cmap[];

	boolean transferInts; // Is transfer type int?.. or byte?
	int dataElementsPerPixel = 1;

	ColorModel cm;

	int updateFromScanline; // First scanline to update
	int numScanlines; // Number of scanlines to update

	private native long decode(byte[] input, int bytesInBuffer, long hDecoder);

	private static native void releaseNativeDecoder(long hDecoder);

	public PngDecoder(DecodingImageSource src, InputStream is) {
	super(src, is);
	}

	@Override
	public void decodeImage() throws IOException {
	try {
	int bytesRead = 0;
	int needBytes, offset, bytesInBuffer = 0;
	// Read from the input stream
	for (;;) {
	needBytes = INPUT_BUFFER_SIZE - bytesInBuffer;
	offset = bytesInBuffer;

	bytesRead = inputStream.read(buffer, offset, needBytes);

	if (bytesRead < 0) { // Break, nothing to read from buffer, image truncated?
	releaseNativeDecoder(hNativeDecoder);
	break;
	}

	// Keep track on how much bytes left in buffer
	bytesInBuffer += bytesRead;
	hNativeDecoder = decode(buffer, bytesInBuffer, hNativeDecoder);
	// PNG decoder always consumes all bytes at once
	bytesInBuffer = 0;

	// if (bytesConsumed < 0)
	//break; // Error exit

	returnData();

	// OK, we decoded all the picture in the right way...
	if (hNativeDecoder == 0) {
	break;
	}
	}

	imageComplete(ImageConsumer.STATICIMAGEDONE);
	} catch (IOException e) {
	throw e;
	} catch (RuntimeException e) {
	imageComplete(ImageConsumer.IMAGEERROR);
	throw e;
	} finally {
	closeStream();
	}
	}

	@SuppressWarnings("unused")
	private void returnHeader() { // Called from native code
	setDimensions(imageWidth, imageHeight);

	switch (colorType) {
	case PNG_COLOR_TYPE_GRAY: {
	if (bitDepth != 8 && bitDepth != 4 && bitDepth != 2 && bitDepth != 1) {
	// awt.3C=Unknown PNG color type
	throw new IllegalArgumentException(Messages.getString("awt.3C")); //$NON-NLS-1$
	}

	// Create gray color model
	int numEntries = 1 << bitDepth;
	int scaleFactor = 255 / (numEntries-1);
	byte comps[] = new byte[numEntries];
	for (int i = 0; i < numEntries; i++) {
	comps[i] = (byte) (i * scaleFactor);
	}
	cm = new IndexColorModel(/bitDepth/8, numEntries, comps, comps, comps);

	transferInts = false;
	break;
	}

	case PNG_COLOR_TYPE_RGB: {
	if (bitDepth != 8) {
	// awt.3C=Unknown PNG color type
	throw new IllegalArgumentException(Messages.getString("awt.3C")); //$NON-NLS-1$
	}

	cm = new DirectColorModel(24, 0xFF0000, 0xFF00, 0xFF);

	transferInts = true;
	break;
	}

	case PNG_COLOR_TYPE_PLTE: {
	if (bitDepth != 8 && bitDepth != 4 && bitDepth != 2 && bitDepth != 1) {
	// awt.3C=Unknown PNG color type
	throw new IllegalArgumentException(Messages.getString("awt.3C")); //$NON-NLS-1$
	}

	cm = new IndexColorModel(/bitDepth/8, cmap.length / 3, cmap, 0, false);

	transferInts = false;
	break;
	}

	case PNG_COLOR_TYPE_GRAY_ALPHA: {
	if (bitDepth != 8) {
	// awt.3C=Unknown PNG color type
	throw new IllegalArgumentException(Messages.getString("awt.3C")); //$NON-NLS-1$
	}

	cm = new ComponentColorModel(ColorSpace.getInstance(ColorSpace.CS_GRAY),
	true, false,
	Transparency.TRANSLUCENT,
	DataBuffer.TYPE_BYTE);

	transferInts = false;
	dataElementsPerPixel = 2;
	break;
	}

	case PNG_COLOR_TYPE_RGBA: {
	if (bitDepth != 8) {
	// awt.3C=Unknown PNG color type
	throw new IllegalArgumentException(Messages.getString("awt.3C")); //$NON-NLS-1$
	}

	cm = ColorModel.getRGBdefault();

	transferInts = true;
	break;
	}
	default:
	// awt.3C=Unknown PNG color type
	throw new IllegalArgumentException(Messages.getString("awt.3C")); //$NON-NLS-1$
	}

	// Create output buffer
	if (transferInts) {
	intOut = new int[imageWidth * imageHeight];
	} else {
	byteOut = new byte[imageWidth * imageHeight * dataElementsPerPixel];
	}

	setColorModel(cm);

	setHints(hintflags);
	setProperties(new Hashtable<Object, Object>()); // Empty
	}

	// Send the data to the consumer
	private void returnData() {
	// Send 1 or more scanlines to the consumer.
	if (numScanlines > 0) {
	// Native decoder could have returned
	// some data from the next pass, handle it here
	int pass1, pass2;
	if (updateFromScanline + numScanlines > imageHeight) {
	pass1 = imageHeight - updateFromScanline;
	pass2 = updateFromScanline + numScanlines - imageHeight;
	} else {
	pass1 = numScanlines;
	pass2 = 0;
	}

	transfer(updateFromScanline, pass1);
	if (pass2 != 0) {
	transfer(0, pass2);
	}
	}
	}

	private void transfer(int updateFromScanline, int numScanlines) {
	if (transferInts) {
	setPixels(
	0, updateFromScanline,
	imageWidth, numScanlines,
	cm, intOut,
	updateFromScanline * imageWidth,
	imageWidth
	);
	} else {
	setPixels(
	0, updateFromScanline,
	imageWidth, numScanlines,
	cm, byteOut,
	updateFromScanline * imageWidth * dataElementsPerPixel,
	imageWidth * dataElementsPerPixel
	);
	}
	}
	}