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Diffstat (limited to 'gcc-4.4.3/libjava/classpath/gnu/javax/imageio/jpeg/JPEGComponent.java')
| -rw-r--r-- | gcc-4.4.3/libjava/classpath/gnu/javax/imageio/jpeg/JPEGComponent.java | 351 |
1 files changed, 351 insertions, 0 deletions
diff --git a/gcc-4.4.3/libjava/classpath/gnu/javax/imageio/jpeg/JPEGComponent.java b/gcc-4.4.3/libjava/classpath/gnu/javax/imageio/jpeg/JPEGComponent.java new file mode 100644 index 000000000..d07bb34e9 --- /dev/null +++ b/gcc-4.4.3/libjava/classpath/gnu/javax/imageio/jpeg/JPEGComponent.java @@ -0,0 +1,351 @@ +/* JPEGComponent.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.jpeg; + +import java.util.ArrayList; +import java.io.IOException; +import java.awt.image.WritableRaster; + +import javax.imageio.plugins.jpeg.JPEGHuffmanTable; + +/** + * This class holds the methods to decode and write a component information to + * a raster. + */ +public class JPEGComponent +{ + public byte factorH, factorV, component_id, quant_id; + public int width = 0, height = 0, maxV = 0, maxH = 0; + public HuffmanTable ACTable; + public HuffmanTable DCTable; + public int[] quantizationTable; + public double previousDC = 0; + ArrayList data = new ArrayList(); + + /** + * Initializes the component + * + * @param id + * @param factorHorizontal + * @param factorVertical + * @param quantizationID + */ + public JPEGComponent(byte id, byte factorHorizontal, byte factorVertical, + byte quantizationID) + { + component_id = id; + factorH = factorHorizontal; + factorV = factorVertical; + quant_id = quantizationID; + } + + /** + * If a restart marker is found with too little of an MCU count (i.e. our + * Restart Interval is 63 and we have 61 we copy the last MCU until it's + * full) + * + * @param index + * @param length + */ + public void padMCU(int index, int length) + { + double[] src = (double[]) data.get(index - 1); + for (int i = 0; i < length; i++) + data.add(index, src); + } + + /** + * Reset the interval by setting the previous DC value + */ + public void resetInterval() + { + previousDC = 0; + } + + /** + * Run the Quantization backward method on all of the block data. + */ + public void quantitizeData() + { + for (int i = 0; i < data.size(); i++) + { + double[] mydata = (double[]) data.get(i); + for (int j = 0; j < mydata.length; j++) + mydata[j] *= quantizationTable[j]; + } + } + + public void setDCTable(JPEGHuffmanTable table) + { + DCTable = new HuffmanTable(table); + } + + public void setACTable(JPEGHuffmanTable table) + { + ACTable = new HuffmanTable(table); + } + + /** + * Run the Inverse DCT method on all of the block data + */ + public void idctData(DCT myDCT) + { + for (int i = 0; i < data.size(); i++) + data.add(i,myDCT.fast_idct(ZigZag.decode8x8_map((double[]) data.remove(i)))); + } + + /** + * This scales up the component size based on the factor size. This + * calculates everyting up automatically so it's simply ran at the end of + * the frame to normalize the size of all of the components. + */ + public void scaleByFactors() + { + int factorUpVertical = maxV / factorV; + int factorUpHorizontal = maxH / factorH; + + if (factorUpVertical > 1) + { + for (int i = 0; i < data.size(); i++) + { + double[][] src = (double[][]) data.remove(i); + double[][] dest = + new double[src.length * factorUpVertical][src[0].length]; + for (int j = 0; j < src.length; j++) + { + for (int u = 0; u < factorUpVertical; u++) + { + dest[j * factorUpVertical + u] = src[j]; + } + } + data.add(i, dest); + } + } + + if (factorUpHorizontal > 1) + { + for (int i = 0; i < data.size(); i++) + { + double[][] src = (double[][]) data.remove(i); + double[][] dest = + new double[src.length][src[0].length * factorUpHorizontal]; + for (int j = 0; j < src.length; j++) + { + for (int u = 0; u < src[0].length; u++) + { + for (int v = 0; v < factorUpHorizontal; v++) + dest[j][u * factorUpHorizontal + v] = src[j][u]; + } + } + data.add(i, dest); + } + } + } + + /** + * This write the block of data to the raster throwing out anything that + * spills over the raster width or height. + * + * @param raster + * @param data + * @param compIndex + * @param x + * @param y + */ + public void writeBlock(WritableRaster raster, double[][] data, + int compIndex, int x, int y) + { + for (int yIndex = 0; yIndex < data.length; yIndex++) + { + for (int xIndex = 0; xIndex < data[yIndex].length; xIndex++) + { + // The if statement is needed because blocks can spill over the + // frame width because they are padded to make sure we keep the + // height of the block the same as the width of the block + if (x + xIndex < raster.getWidth() + && y + yIndex < raster.getHeight()) + raster.setSample(x + xIndex, y + yIndex, compIndex, + data[yIndex][xIndex]); + } + } + } + + /** + * This writes data to a raster block, so really it's reading not writing + * but it writes the data to the raster block by factor size in a zig zag + * fashion. This has the helper function writeBlock which does the actual + * writing. + * + * @param raster + * @param componentIndex + */ + public void writeData(WritableRaster raster, int componentIndex) + { + int x = 0, y = 0, lastblockheight = 0, incrementblock = 0; + + // Keep looping through all of the blocks until there are no more. + while(data.size() > 0) + { + int blockwidth = 0; + int blockheight = 0; + + if (x >= raster.getWidth()) + { + x = 0; + y += incrementblock; + } + + // Loop through the horizontal component blocks of the MCU first + // then for each horizontal line write out all of the vertical + // components + for (int factorVIndex = 0; factorVIndex < factorV; factorVIndex++) + { + blockwidth = 0; + + for (int factorHIndex = 0; factorHIndex < factorH; factorHIndex++) + { + // Captures the width of this block so we can increment the + // X coordinate + double[][] blockdata = (double[][]) data.remove(0); + + // Writes the data at the specific X and Y coordinate of + // this component + writeBlock(raster, blockdata, componentIndex, x, y); + blockwidth += blockdata[0].length; + x += blockdata[0].length; + blockheight = blockdata.length; + } + y += blockheight; + x -= blockwidth; + lastblockheight += blockheight; + } + y -= lastblockheight; + incrementblock = lastblockheight; + lastblockheight = 0; + x += blockwidth; + } + } + + /** + * Set the quantization table for this component. + * + * @param quanttable + */ + public void setQuantizationTable(int[] quanttable) + { + quantizationTable = quanttable; + } + + /** + * Read in a partial MCU for this component + * + * @param stream TODO + * @throws JPEGException TODO + * @throws IOException TODO + */ + public void readComponentMCU(JPEGImageInputStream stream) + throws JPEGException, IOException + { + for (int i = 0; i < factorH * factorV; i++) + { + double dc = decode_dc_coefficient(stream); + double[] datablock = decode_ac_coefficients(stream); + datablock[0] = dc; + data.add(datablock); + } + } + + /** + * Generated from text on F-22, F.2.2.1 - Huffman decoding of DC + * coefficients on ISO DIS 10918-1. Requirements and Guidelines. + * + * @param JPEGStream TODO + * + * @return TODO + * @throws JPEGException TODO + * @throws IOException TODO + */ + public double decode_dc_coefficient(JPEGImageInputStream JPEGStream) + throws JPEGException, IOException + { + int t = DCTable.decode(JPEGStream); + double diff = JPEGStream.readBits(t); + diff = HuffmanTable.extend((int) diff, t); + diff = (previousDC + diff); + previousDC = diff; + return diff; + } + + /** + * Generated from text on F-23, F.13 - Huffman decoded of AC coefficients + * on ISO DIS 10918-1. Requirements and Guidelines. + * + * @param JPEGStream TODO + * @return TODO + * + * @throws JPEGException TODO + * @throws IOException TODO + */ + public double[] decode_ac_coefficients(JPEGImageInputStream JPEGStream) + throws JPEGException, IOException + { + double[] zz = new double[64]; + + for (int k = 1; k < 64; k++) + { + int s = ACTable.decode(JPEGStream); + int r = s >> 4; + s &= 15; + + if (s != 0) + { + k += r; + r = (int) JPEGStream.readBits(s); + s = HuffmanTable.extend(r, s); + zz[k] = s; + } + else + { + if (r != 15) + return (zz); + k += 15; + } + } + return zz; + } +} |