+/*
+ * Imagesqueeze - Image codec optimized for photos.
+ * Copyright (C) 2012, Svjatoslav Agejenko, svjatoslav@svjatoslav.eu
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public License
+ * as published by the Free Software Foundation.
+ */
+
package eu.svjatoslav.imagesqueeze.codec;
/**
import java.awt.image.WritableRaster;
import java.io.IOException;
+import eu.svjatoslav.commons.data.BitInputStream;
+
public class ImageDecoder {
int width, height;
Image image;
- byte [] decodedYRangeMap;
- byte [] decodedYMap;
+ byte[] decodedYRangeMap;
+ byte[] decodedYMap;
- byte [] decodedURangeMap;
- byte [] decodedUMap;
+ byte[] decodedURangeMap;
+ byte[] decodedUMap;
- byte [] decodedVRangeMap;
- byte [] decodedVMap;
+ byte[] decodedVRangeMap;
+ byte[] decodedVMap;
Color tmpColor = new Color();
-
+
Approximator approximator;
BitInputStream bitInputStream;
-
+
ColorStats colorStats = new ColorStats();
OperatingContext context = new OperatingContext();
-
- public ImageDecoder (Image image, BitInputStream bitInputStream) {
+
+ public ImageDecoder(final Image image, final BitInputStream bitInputStream) {
approximator = new Approximator();
- this.image = image;
+ this.image = image;
this.bitInputStream = bitInputStream;
width = image.metaData.width;
height = image.metaData.height;
decodedYRangeMap = new byte[width * height];
- decodedYRangeMap[0] = (byte)(255);
+ decodedYRangeMap[0] = (byte) (255);
decodedYMap = new byte[width * height];
decodedURangeMap = new byte[width * height];
- decodedURangeMap[0] = (byte)(255);
+ decodedURangeMap[0] = (byte) (255);
decodedUMap = new byte[width * height];
decodedVRangeMap = new byte[width * height];
- decodedVRangeMap[0] = (byte)(255);
+ decodedVRangeMap[0] = (byte) (255);
decodedVMap = new byte[width * height];
}
-
public void decode() throws IOException {
approximator.load(bitInputStream);
approximator.computeLookupTables();
-
- WritableRaster raster = image.bufferedImage.getRaster();
- DataBufferByte dbi = (DataBufferByte)raster.getDataBuffer();
- byte [] pixels = dbi.getData();
-
- // load top-, left-most pixel.
- decodedYMap[0] = (byte)bitInputStream.readBits(8);
- decodedUMap[0] = (byte)bitInputStream.readBits(8);
- decodedVMap[0] = (byte)bitInputStream.readBits(8);
-
- Color color = new Color();
+
+ final WritableRaster raster = image.bufferedImage.getRaster();
+ final DataBufferByte dbi = (DataBufferByte) raster.getDataBuffer();
+ final byte[] pixels = dbi.getData();
+
+ // load top-, left-most pixel.
+ decodedYMap[0] = (byte) bitInputStream.readBits(8);
+ decodedUMap[0] = (byte) bitInputStream.readBits(8);
+ decodedVMap[0] = (byte) bitInputStream.readBits(8);
+
+ final Color color = new Color();
color.y = ImageEncoder.byteToInt(decodedYMap[0]);
color.u = ImageEncoder.byteToInt(decodedUMap[0]);
color.v = ImageEncoder.byteToInt(decodedVMap[0]);
-
+
color.YUV2RGB();
-
- pixels[0] = (byte)color.r;
- pixels[0+1] = (byte)color.g;
- pixels[0+2] = (byte)color.b;
-
+ pixels[0] = (byte) color.r;
+ pixels[0 + 1] = (byte) color.g;
+ pixels[0 + 2] = (byte) color.b;
+
// detect initial step
int largestDimension;
int initialStep = 2;
} else {
largestDimension = height;
}
-
- while (initialStep < largestDimension){
+
+ while (initialStep < largestDimension) {
initialStep = initialStep * 2;
}
grid(initialStep, pixels);
}
-
- public void grid(int step, byte [] pixels) throws IOException {
+ public void grid(final int step, final byte[] pixels) throws IOException {
gridDiagonal(step / 2, step / 2, step, pixels);
gridSquare(step / 2, 0, step, pixels);
gridSquare(0, step / 2, step, pixels);
- if (step > 2) grid(step / 2, pixels);
- }
-
-
- public void gridSquare(int offsetX, int offsetY, int step, byte [] pixels) throws IOException{
-
- for (int y = offsetY; y < height; y = y + step){
- for (int x = offsetX; x < width; x = x + step){
-
-
- int halfStep = step / 2;
-
- context.initialize(image, decodedYMap, decodedUMap, decodedVMap);
- context.measureNeighborEncode(x - halfStep, y);
- context.measureNeighborEncode(x + halfStep, y);
- context.measureNeighborEncode(x, y - halfStep);
- context.measureNeighborEncode(x, y + halfStep);
-
- loadPixel(step, offsetX, offsetY, x, y, pixels,
- context.colorStats.getAverageY(),
- context.colorStats.getAverageU(),
- context.colorStats.getAverageV());
-
- }
- }
+ if (step > 2) {
+ grid(step / 2, pixels);
+ }
}
+ public void gridDiagonal(final int offsetX, final int offsetY,
+ final int step, final byte[] pixels) throws IOException {
- public void gridDiagonal(int offsetX, int offsetY, int step, byte [] pixels) throws IOException{
+ for (int y = offsetY; y < height; y = y + step) {
+ for (int x = offsetX; x < width; x = x + step) {
- for (int y = offsetY; y < height; y = y + step){
- for (int x = offsetX; x < width; x = x + step){
-
- int halfStep = step / 2;
+ final int halfStep = step / 2;
context.initialize(image, decodedYMap, decodedUMap, decodedVMap);
context.measureNeighborEncode(x - halfStep, y - halfStep);
context.measureNeighborEncode(x + halfStep, y - halfStep);
context.measureNeighborEncode(x - halfStep, y + halfStep);
context.measureNeighborEncode(x + halfStep, y + halfStep);
-
- loadPixel(step, offsetX, offsetY, x, y, pixels,
+
+ loadPixel(step, offsetX, offsetY, x, y, pixels,
context.colorStats.getAverageY(),
context.colorStats.getAverageU(),
context.colorStats.getAverageV());
- }
- }
+ }
+ }
}
+ public void gridSquare(final int offsetX, final int offsetY,
+ final int step, final byte[] pixels) throws IOException {
- public void loadPixel(int step, int offsetX, int offsetY, int x, int y, byte[] pixels,
- int averageDecodedY, int averageDecodedU, int averageDecodedV)
- throws IOException{
-
- int index = (y * width) + x;
+ for (int y = offsetY; y < height; y = y + step) {
+ for (int x = offsetX; x < width; x = x + step) {
- int halfStep = step / 2;
+ final int halfStep = step / 2;
- int parentIndex;
- if (offsetX > 0){
- if (offsetY > 0){
- // diagonal approach
- parentIndex = ((y - halfStep) * width) + (x - halfStep);
- } else {
- // take left pixel
- parentIndex = (y * width) + (x - halfStep);
- }
- } else {
- // take upper pixel
- parentIndex = ((y - halfStep) * width) + x;
- }
-
-
-
- int colorBufferIndex = index * 3;
+ context.initialize(image, decodedYMap, decodedUMap, decodedVMap);
+ context.measureNeighborEncode(x - halfStep, y);
+ context.measureNeighborEncode(x + halfStep, y);
+ context.measureNeighborEncode(x, y - halfStep);
+ context.measureNeighborEncode(x, y + halfStep);
- Color color = new Color();
- color.y = loadChannel(decodedYRangeMap, decodedYMap, approximator.yTable, averageDecodedY, index, parentIndex);
- color.u = loadChannel(decodedURangeMap, decodedUMap, approximator.uTable, averageDecodedU, index, parentIndex);
- color.v = loadChannel(decodedVRangeMap, decodedVMap, approximator.vTable, averageDecodedV, index, parentIndex);
-
- color.YUV2RGB();
-
- pixels[colorBufferIndex] = (byte)color.r;
- pixels[colorBufferIndex+1] = (byte)color.g;
- pixels[colorBufferIndex+2] = (byte)color.b;
+ loadPixel(step, offsetX, offsetY, x, y, pixels,
+ context.colorStats.getAverageY(),
+ context.colorStats.getAverageU(),
+ context.colorStats.getAverageV());
+ }
+ }
}
-
- private int loadChannel(byte [] decodedRangeMap, byte [] decodedMap, Table table, int averageDecodedValue, int index,
- int parentIndex) throws IOException {
+ private int loadChannel(final byte[] decodedRangeMap,
+ final byte[] decodedMap, final Table table,
+ final int averageDecodedValue, final int index,
+ final int parentIndex) throws IOException {
int decodedValue = averageDecodedValue;
- int inheritedRange = ImageEncoder.byteToInt(decodedRangeMap[parentIndex]);
+ final int inheritedRange = ImageEncoder
+ .byteToInt(decodedRangeMap[parentIndex]);
int computedRange = inheritedRange;
- int bitCount = table.proposeBitcountForRange(inheritedRange);
+ final int bitCount = table.proposeBitcountForRange(inheritedRange);
int computedRangeBitCount = 0;
- if ( bitCount > 0){
+ if (bitCount > 0) {
- int rangeDecreases = bitInputStream.readBits(1);
- if (rangeDecreases != 0){
+ final int rangeDecreases = bitInputStream.readBits(1);
+ if (rangeDecreases != 0) {
computedRange = table.proposeDecreasedRange(inheritedRange);
- }
+ }
- decodedRangeMap[index] = (byte)computedRange;
- computedRangeBitCount = table.proposeBitcountForRange(computedRange);
+ decodedRangeMap[index] = (byte) computedRange;
+ computedRangeBitCount = table
+ .proposeBitcountForRange(computedRange);
- if (computedRangeBitCount > 0){
+ if (computedRangeBitCount > 0) {
- int encodedDifference = bitInputStream.readBits(computedRangeBitCount);
+ final int encodedDifference = bitInputStream
+ .readBits(computedRangeBitCount);
- int decodedDifference = ImageEncoder.decodeValueFromGivenBits(encodedDifference, computedRange, computedRangeBitCount);
+ final int decodedDifference = ImageEncoder
+ .decodeValueFromGivenBits(encodedDifference,
+ computedRange, computedRangeBitCount);
decodedValue = averageDecodedValue - decodedDifference;
- if (decodedValue > 255) decodedValue = 255;
- if (decodedValue < 0) decodedValue = 0;
+ if (decodedValue > 255) {
+ decodedValue = 255;
+ }
+ if (decodedValue < 0) {
+ decodedValue = 0;
+ }
}
} else {
- decodedRangeMap[index] = (byte)inheritedRange;
+ decodedRangeMap[index] = (byte) inheritedRange;
}
- decodedMap[index] = (byte)decodedValue;
+ decodedMap[index] = (byte) decodedValue;
return decodedValue;
}
+ public void loadPixel(final int step, final int offsetX, final int offsetY,
+ final int x, final int y, final byte[] pixels,
+ final int averageDecodedY, final int averageDecodedU,
+ final int averageDecodedV) throws IOException {
+
+ final int index = (y * width) + x;
+
+ final int halfStep = step / 2;
+
+ int parentIndex;
+ if (offsetX > 0) {
+ if (offsetY > 0) {
+ // diagonal approach
+ parentIndex = ((y - halfStep) * width) + (x - halfStep);
+ } else {
+ // take left pixel
+ parentIndex = (y * width) + (x - halfStep);
+ }
+ } else {
+ // take upper pixel
+ parentIndex = ((y - halfStep) * width) + x;
+ }
+
+ final int colorBufferIndex = index * 3;
+
+ final Color color = new Color();
+ color.y = loadChannel(decodedYRangeMap, decodedYMap,
+ approximator.yTable, averageDecodedY, index, parentIndex);
+ color.u = loadChannel(decodedURangeMap, decodedUMap,
+ approximator.uTable, averageDecodedU, index, parentIndex);
+ color.v = loadChannel(decodedVRangeMap, decodedVMap,
+ approximator.vTable, averageDecodedV, index, parentIndex);
+
+ color.YUV2RGB();
+
+ pixels[colorBufferIndex] = (byte) color.r;
+ pixels[colorBufferIndex + 1] = (byte) color.g;
+ pixels[colorBufferIndex + 2] = (byte) color.b;
+
+ }
+
}
projects / imagesqueeze.git / blobdiff