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diff --git a/gcc-4.4.3/libjava/classpath/gnu/javax/imageio/png/PNGDecoder.java b/gcc-4.4.3/libjava/classpath/gnu/javax/imageio/png/PNGDecoder.java
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+/* PNGDecoder.java
+ Copyright (C) 2006 Free Software Foundation
+
+This file is part of GNU Classpath.
+
+GNU Classpath is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+GNU Classpath 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
+General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Classpath; see the file COPYING. If not, write to the
+Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library. Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module. An independent module is a module which is not derived from
+or based on this library. If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so. If you do not wish to do so, delete this
+exception statement from your version. */
+
+package gnu.javax.imageio.png;
+
+import java.util.zip.Inflater;
+import java.util.zip.DataFormatException;
+import java.awt.image.ColorModel;
+import java.awt.image.ComponentColorModel;
+import java.awt.image.ComponentSampleModel;
+import java.awt.image.DataBuffer;
+import java.awt.image.DataBufferByte;
+import java.awt.image.DataBufferUShort;
+import java.awt.image.IndexColorModel;
+import java.awt.image.MultiPixelPackedSampleModel;
+import java.awt.image.Raster;
+import java.awt.image.SampleModel;
+import java.awt.image.SinglePixelPackedSampleModel;
+import java.awt.image.WritableRaster;
+import java.awt.color.ColorSpace;
+
+public class PNGDecoder
+{
+ private PNGHeader header;
+ private byte[] raster;
+ private byte[] scanline, lastScanline;
+ private byte[] filterType;
+ private int offset, length;
+ private int currentScanline;
+ private final int stride;
+ private Inflater inflater;
+ private boolean readFilter;
+ private int bpp; // bytes per pixel
+
+ /**
+ * Constructs a filter object for
+ */
+ public PNGDecoder(PNGHeader header)
+ {
+ this.header = header;
+ offset = 0;
+ inflater = new Inflater();
+ stride = header.getScanlineStride();
+ length = stride * header.getHeight();
+
+ // Allocate the output raster
+ raster = new byte[ length ];
+ scanline = new byte[ stride ];
+ lastScanline = new byte[ stride ];
+ currentScanline = 0;
+ readFilter = true;
+ bpp = header.bytesPerPixel();
+ filterType = new byte[1];
+ inflater = new Inflater();
+ }
+
+ private int getBytes( byte[] buf, int offset ) throws PNGException
+ {
+ try
+ {
+ return inflater.inflate( buf, offset, buf.length - offset);
+ }
+ catch(DataFormatException dfe)
+ {
+ throw new PNGException("Error inflating data.");
+ }
+ }
+
+ /**
+ * Decodes a data chunk.
+ */
+ public void addData( PNGData chunk ) throws PNGException
+ {
+ int n = 0;
+ if( isFinished() )
+ return;
+ chunk.feedToInflater( inflater );
+ do
+ {
+ if( readFilter )
+ if( getBytes( filterType, 0 ) < 1 )
+ return;
+
+ n = getBytes( scanline, offset );
+
+ if( offset + n < stride )
+ {
+ offset += n;
+ readFilter = false;
+ }
+ else
+ {
+ scanline = PNGFilter.unFilterScanline( filterType[0], scanline,
+ lastScanline, bpp );
+ System.arraycopy( scanline, 0,
+ raster, currentScanline * stride, stride );
+ lastScanline = scanline;
+ scanline = new byte[scanline.length];
+ currentScanline++;
+ readFilter = true;
+ offset = 0;
+ }
+ }
+ while( n > 0 && currentScanline < header.getHeight() );
+ }
+
+ /**
+ * Parse the appropriate color type and create an AWT raster for it.
+ * @param header - the file header.
+ */
+ public WritableRaster getRaster( PNGHeader header )
+ {
+ SampleModel sm = null;
+ DataBuffer db = null;
+ int t;
+ int width = header.getWidth();
+ int height = header.getHeight();
+ int depth = header.getDepth();
+
+ switch( header.getColorType() )
+ {
+ case PNGHeader.GRAYSCALE_WITH_ALPHA:
+ if( depth == 8 )
+ {
+ t = DataBuffer.TYPE_BYTE;
+ db = getByteBuffer();
+ }
+ else
+ {
+ t = DataBuffer.TYPE_USHORT;
+ db = getShortBuffer();
+ }
+ sm = new ComponentSampleModel(t, width, height, 2, width * 2,
+ new int[]{0, 1});
+ break;
+
+ case PNGHeader.GRAYSCALE:
+ switch( depth )
+ {
+ case 16:
+ sm = new ComponentSampleModel(DataBuffer.TYPE_USHORT,
+ width, height, 1, width,
+ new int[]{ 0 });
+ db = getShortBuffer();
+ break;
+
+ case 8:
+ sm = new ComponentSampleModel(DataBuffer.TYPE_BYTE,
+ width, height, 1, width,
+ new int[]{ 0 });
+ db = getByteBuffer();
+ break;
+
+ default:
+ sm = new MultiPixelPackedSampleModel(DataBuffer.TYPE_BYTE,
+ width, height, depth);
+ db = getByteBuffer();
+ break;
+ }
+ break;
+
+ case PNGHeader.RGB:
+ if( depth == 8 )
+ {
+ t = DataBuffer.TYPE_BYTE;
+ db = getByteBuffer();
+ }
+ else
+ {
+ t = DataBuffer.TYPE_USHORT;
+ db = getShortBuffer();
+ }
+ sm = new ComponentSampleModel(t, width, height, 3, 3 * width,
+ new int[]{0, 1, 2});
+ break;
+
+ case PNGHeader.RGB_WITH_ALPHA:
+ if( depth == 8 )
+ {
+ t = DataBuffer.TYPE_BYTE;
+ db = getByteBuffer();
+ }
+ else
+ {
+ t = DataBuffer.TYPE_USHORT;
+ db = getShortBuffer();
+ }
+
+ sm = new ComponentSampleModel(t, width, height, 4, width * 4,
+ new int[]{0, 1, 2, 3});
+ break;
+
+ case PNGHeader.INDEXED:
+ if( depth == 8 )
+ sm = new SinglePixelPackedSampleModel(DataBuffer.TYPE_BYTE,
+ width, height,
+ new int[] {0xFF});
+ else
+ sm = new MultiPixelPackedSampleModel(DataBuffer.TYPE_BYTE,
+ width, height, depth);
+ db = getByteBuffer();
+ break;
+ }
+
+ return Raster.createWritableRaster(sm, db, null);
+ }
+
+ /**
+ * Wrap the raster with a DataBufferUShort,
+ * conversion is big-endian (PNG native).
+ */
+ private DataBuffer getShortBuffer()
+ {
+ short[] data = new short[(raster.length >> 1)];
+ for( int i = 0; i < data.length; i++ )
+ data[i] = (short)(((raster[i * 2] & 0xFF) << 8) |
+ (raster[i * 2 + 1] & 0xFF));
+ return new DataBufferUShort( data, data.length );
+ }
+
+ /**
+ * Wrap the raster with a DataBufferByte
+ */
+ private DataBuffer getByteBuffer()
+ {
+ return new DataBufferByte( raster, raster.length );
+ }
+
+ public ColorModel getColorModel( ColorSpace cs,
+ int colorType, int depth )
+ {
+ int[] bits;
+ boolean hasAlpha = false;
+ int transferType;
+
+ switch( colorType )
+ {
+ case PNGHeader.GRAYSCALE_WITH_ALPHA:
+ if( cs == null )
+ cs = ColorSpace.getInstance( ColorSpace.CS_GRAY );
+ hasAlpha = true;
+ bits = new int[]{ depth, depth };
+ break;
+
+ case PNGHeader.RGB:
+ bits = new int[]{ depth, depth, depth };
+ break;
+
+ case PNGHeader.RGB_WITH_ALPHA:
+ hasAlpha = true;
+ bits = new int[]{ depth, depth, depth, depth };
+ break;
+
+ case PNGHeader.GRAYSCALE:
+ if( depth < 8 )
+ return grayPalette( depth );
+
+ if( cs == null )
+ cs = ColorSpace.getInstance( ColorSpace.CS_GRAY );
+ bits = new int[]{ depth };
+ break;
+
+ default:
+ case PNGHeader.INDEXED:
+ return null; // Handled by the palette chunk.
+ }
+
+ if( cs == null )
+ cs = ColorSpace.getInstance( ColorSpace.CS_sRGB );
+
+
+ return new ComponentColorModel(cs, bits, hasAlpha, false,
+ (hasAlpha ?
+ ComponentColorModel.TRANSLUCENT :
+ ComponentColorModel.OPAQUE),
+ ((depth == 16) ? DataBuffer.TYPE_USHORT :
+ DataBuffer.TYPE_BYTE));
+ }
+
+ private IndexColorModel grayPalette(int depth)
+ {
+ byte[] c = new byte[ (1 << depth) ];
+ for(int i = 0; i < c.length; i++)
+ c[i] = (byte)(255.0 * (((double)i) / ((double)c.length - 1.0)));
+ return new IndexColorModel(8, c.length, c, c, c);
+ }
+
+ public byte[] getRaster()
+ {
+ return raster;
+ }
+
+ public boolean isFinished()
+ {
+ return currentScanline >= header.getHeight();
+ }
+}
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