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Diffstat (limited to 'gcc-4.4.3/libjava/classpath/gnu/javax/imageio/bmp/BMPDecoder.java')
| -rw-r--r-- | gcc-4.4.3/libjava/classpath/gnu/javax/imageio/bmp/BMPDecoder.java | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/gcc-4.4.3/libjava/classpath/gnu/javax/imageio/bmp/BMPDecoder.java b/gcc-4.4.3/libjava/classpath/gnu/javax/imageio/bmp/BMPDecoder.java new file mode 100644 index 000000000..df53f2e3d --- /dev/null +++ b/gcc-4.4.3/libjava/classpath/gnu/javax/imageio/bmp/BMPDecoder.java @@ -0,0 +1,168 @@ +/* BMPDecoder.java -- + Copyright (C) 2005 Free Software Foundation, Inc. + +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.bmp; + +import java.io.IOException; +import javax.imageio.stream.ImageInputStream; +import java.nio.ByteBuffer; +import java.nio.ByteOrder; +import java.awt.image.IndexColorModel; +import java.awt.image.BufferedImage; + +public abstract class BMPDecoder { + + protected BMPInfoHeader infoHeader; + protected BMPFileHeader fileHeader; + protected long offset; + + public BMPDecoder(BMPFileHeader fh, BMPInfoHeader ih){ + fileHeader = fh; + infoHeader = ih; + offset = BMPFileHeader.SIZE + BMPInfoHeader.SIZE; + } + + /** + * Determines the coding type of the bitmap and returns the corresponding + * decoder. + */ + public static BMPDecoder getDecoder(BMPFileHeader fh, BMPInfoHeader ih){ + switch(ih.getCompression()){ + case BMPInfoHeader.BI_RGB: // uncompressed RGB + switch(ih.getBitCount()){ + case 32: + return new DecodeBF32(fh, ih, true); + + case 24: + return new DecodeRGB24(fh, ih); + + case 16: + return new DecodeBF16(fh, ih, true); + + case 8: + return new DecodeRGB8(fh, ih); + + case 4: + return new DecodeRGB4(fh, ih); + + case 1: + return new DecodeRGB1(fh, ih); + + default: + return null; + } + + case BMPInfoHeader.BI_RLE8: + return new DecodeRLE8(fh, ih); + + case BMPInfoHeader.BI_RLE4: + return new DecodeRLE4(fh, ih); + + case BMPInfoHeader.BI_BITFIELDS: + switch(ih.getBitCount()){ + case 16: + return new DecodeBF16(fh, ih, false); + + case 32: + return new DecodeBF32(fh, ih, false); + + default: + return null; + } + + default: + return null; + } + } + + /** + * The image decoder. + */ + public abstract BufferedImage decode(ImageInputStream in) + throws IOException, BMPException; + + /** + * Reads r,g,b bit masks from an inputstream + */ + protected int[] readBitMasks(ImageInputStream in) throws IOException { + int[] bitmasks = new int[3]; + byte[] temp = new byte[12]; + if(in.read(temp) != 12) + throw new IOException("Couldn't read bit masks."); + offset += 12; + + ByteBuffer buf = ByteBuffer.wrap(temp); + buf.order(ByteOrder.LITTLE_ENDIAN); + bitmasks[0] = buf.getInt(); + bitmasks[1] = buf.getInt(); + bitmasks[2] = buf.getInt(); + return bitmasks; + } + + /** + * Reads an N-color palette from an inputstream in RGBQUAD format and + * returns an equivalent ColorModel object + */ + protected IndexColorModel readPalette(ImageInputStream in) throws IOException { + int N = infoHeader.getNumberOfPaletteEntries(); + byte[] r = new byte[N]; + byte[] g = new byte[N]; + byte[] b = new byte[N]; + for(int i=0;i<N;i++){ + byte[] RGBquad = new byte[4]; + if(in.read(RGBquad) != 4) + throw new IOException("Error reading palette information."); + // RGBQUAD structure is b,g,r,0 + r[i] = RGBquad[2]; + g[i] = RGBquad[1]; + b[i] = RGBquad[0]; + } + + offset += 4*N; + return new IndexColorModel(8, N, r, g, b); + } + + /** + * Read bytes to the start of the image data + */ + protected void skipToImage(ImageInputStream in) throws IOException { + byte[] d = new byte[1]; + long n = fileHeader.getOffset() - offset; + for(int i=0;i<n;i++) + in.read(d); + } +} |