com.idrsolutions.image.jpeg2000.Tier1Decoder Maven / Gradle / Ivy
/*
* ===========================================
* Java Pdf Extraction Decoding Access Library
* ===========================================
*
* Project Info: http://www.idrsolutions.com
* Help section for developers at http://www.idrsolutions.com/support/
*
* (C) Copyright 1997-2015 IDRsolutions and Contributors.
*
* This file is part of JPedal/JPDF2HTML5
*
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* ---------------
* Tier1Decoder.java
* ---------------
*/
package com.idrsolutions.image.jpeg2000;
/**
*
*/
public class Tier1Decoder {
public static final byte BYTEMB = 0;
public static final byte SHORTMB = 1;
public static final byte INTMB = 2;
private static final byte UNIFORM = 17;
private static final byte RUNLENGTH = 18;
private final int width;
private final int height;
private EntropyDecoder decoder;
private final byte[] contextLableTable;
public byte[] neighborSigns;
public byte[] coefficientsSign;
public Object magnitude;
public byte[] currentFlag;
public byte[] bitsDecoded;
public byte[] cx;
public final int mbType;
public Tier1Decoder(int width, int height, TileBand subband, int zeroBitPlanes, int mb) {
this.width = width;
this.height = height;
this.contextLableTable = (subband.type == TileBand.HH ? LUT.ContextHH
: (subband.type == TileBand.HL ? LUT.ContextHL : LUT.ContextLL));
int cc = width * height;
neighborSigns = new byte[cc];
coefficientsSign = new byte[cc];
mbType = mb > 14 ? INTMB : (mb > 6 ? SHORTMB : BYTEMB);
magnitude = mb > 14 ? new int[cc] : (mb > 6 ? new short[cc] : new byte[cc]);
currentFlag = new byte[cc];
bitsDecoded = new byte[cc];
if (zeroBitPlanes != 0) {
for (int i = 0; i < cc; i++) {
bitsDecoded[i] = (byte) zeroBitPlanes;
}
}
cx = new byte[19];
cx[0] = 4 << 1;
cx[UNIFORM] = 46 << 1;
cx[RUNLENGTH] = 3 << 1;
}
public void setDecoder(EntropyDecoder decoder) {
this.decoder = decoder;
}
public void setNeighborSigns(int y, int x, int index) {
boolean left = x > 0;
boolean right = (x + 1) < width;
if (y > 0) {
int i = index - width;
if (left) {
neighborSigns[i - 1] = (byte) ((neighborSigns[i - 1] & 0xff) + 0x10);
}
if (right) {
neighborSigns[i + 1] = (byte) ((neighborSigns[i + 1] & 0xff) + 0x10);
}
neighborSigns[i] = (byte) ((neighborSigns[i] & 0xff) + 0x04);
}
if ((y + 1) < height) {
int i = index + width;
if (left) {
neighborSigns[i - 1] = (byte) ((neighborSigns[i - 1] & 0xff) + 0x10);
}
if (right) {
neighborSigns[i + 1] = (byte) ((neighborSigns[i + 1] & 0xff) + 0x10);
}
neighborSigns[i] = (byte) ((neighborSigns[i] & 0xff) + 0x04);
}
if (left) {
neighborSigns[index - 1] = (byte) ((neighborSigns[index - 1] & 0xff) + 0x01);
}
if (right) {
neighborSigns[index + 1] = (byte) ((neighborSigns[index + 1] & 0xff) + 0x01);
}
neighborSigns[index] = (byte) ((neighborSigns[index] & 0xff) | 0x80);
}
public void runSPP() {
int processedInverseMask = ~1;
int processedMask = 1;
int firstMagnitudeBitMask = 2;
for (int i0 = 0; i0 < height; i0 += 4) {
for (int j = 0; j < width; j++) {
int index = i0 * width + j;
for (int i1 = 0; i1 < 4; i1++, index += width) {
int i = i0 + i1;
if (i >= height) {
break;
}
currentFlag[index] = (byte) ((currentFlag[index] & 0xff) & processedInverseMask);
switch (mbType) {
case BYTEMB:
if (((byte[]) magnitude)[index] != 0 || neighborSigns[index] == 0) {
continue;
}
break;
case SHORTMB:
if (((short[]) magnitude)[index] != 0 || neighborSigns[index] == 0) {
continue;
}
break;
case INTMB:
if (((int[]) magnitude)[index] != 0 || neighborSigns[index] == 0) {
continue;
}
break;
}
int contextLabel = contextLableTable[(neighborSigns[index] & 0xff)];
int decision = decoder.decodeBit(cx, contextLabel);
if (decision != 0) {
int sign = decodeSignBit(i, j, index);
coefficientsSign[index] = (byte) sign;
switch (mbType) {
case BYTEMB:
((byte[]) magnitude)[index] = 1;
break;
case SHORTMB:
((short[]) magnitude)[index] = 1;
break;
case INTMB:
((int[]) magnitude)[index] = 1;
break;
}
setNeighborSigns(i, j, index);
currentFlag[index] = (byte) ((currentFlag[index] & 0xff) | firstMagnitudeBitMask);
}
bitsDecoded[index]++;
currentFlag[index] = (byte) ((currentFlag[index] & 0xff) | processedMask);
}
}
}
}
private long getCoMag(int pos){
switch (mbType) {
case BYTEMB:
return ((byte[]) magnitude)[pos] & 0xff;
case SHORTMB:
return ((short[]) magnitude)[pos] & 0xffff;
case INTMB:
return ((int[]) magnitude)[pos];
}
return 0;
}
public int decodeSignBit(int y, int x, int index) {
int contribution, sign0, sign1, contextLabel, decoded;
boolean significance1;
significance1 = (x > 0 && getCoMag(index - 1) != 0);
if (x + 1 < width && getCoMag(index + 1) != 0) {
sign1 = coefficientsSign[index + 1] & 0xff;
if (significance1) {
sign0 = coefficientsSign[index - 1] & 0xff;
contribution = 1 - sign1 - sign0;
} else {
contribution = 1 - sign1 - sign1;
}
} else if (significance1) {
sign0 = coefficientsSign[index - 1] & 0xff;
contribution = 1 - sign0 - sign0;
} else {
contribution = 0;
}
int horizontalContribution = 3 * contribution;
significance1 = (y > 0 && getCoMag(index - width) != 0);
if (y + 1 < height && getCoMag(index + width) != 0) {
sign1 = coefficientsSign[index + width] & 0xff;
if (significance1) {
sign0 = coefficientsSign[index - width] & 0xff;
contribution = 1 - sign1 - sign0 + horizontalContribution;
} else {
contribution = 1 - sign1 - sign1 + horizontalContribution;
}
} else if (significance1) {
sign0 = coefficientsSign[index - width] & 0xff;
contribution = 1 - sign0 - sign0 + horizontalContribution;
} else {
contribution = horizontalContribution;
}
if (contribution >= 0) {
contextLabel = 9 + contribution;
decoded = decoder.decodeBit(cx, contextLabel);
} else {
contextLabel = 9 - contribution;
decoded = decoder.decodeBit(cx, contextLabel) ^ 1;
}
return decoded;
}
public void runMRP() {
int processedMask = 1;
int msbMask = 2;
int dim = width * height;
int width4 = width * 4;
int indexNext;
for (int idx0 = 0; idx0 < dim; idx0 = indexNext) {
indexNext = Math.min(dim, idx0 + width4);
for (int j = 0; j < width; j++) {
for (int index = idx0 + j; index < indexNext; index += width) {
long cmIndex = 0;
switch (mbType) {
case BYTEMB:
cmIndex = ((byte[]) magnitude)[index] & 0xff;
break;
case SHORTMB:
cmIndex = ((short[]) magnitude)[index] & 0xffff;
break;
case INTMB:
cmIndex = ((int[]) magnitude)[index];
break;
}
if (cmIndex == 0 || ((currentFlag[index] & 0xff) & processedMask) != 0) {
continue;
}
int contextLabel = 16;
if (((currentFlag[index] & 0xff) & msbMask) != 0) {
currentFlag[index] = (byte) ((currentFlag[index] & 0xff) ^ msbMask);
int significance = (neighborSigns[index] & 0xff) & 127;
contextLabel = significance == 0 ? 15 : 14;
}
int bit = decoder.decodeBit(cx, contextLabel);
switch (mbType) {
case BYTEMB:
((byte[]) magnitude)[index] = (byte) ((cmIndex << 1) | bit);
break;
case SHORTMB:
((short[]) magnitude)[index] = (short) ((cmIndex << 1) | bit);
break;
case INTMB:
((int[]) magnitude)[index] = (int) ((cmIndex << 1) | bit);
break;
}
bitsDecoded[index]++;
currentFlag[index] = (byte) ((currentFlag[index] & 0xff) | processedMask);
}
}
}
}
public void runCP() {
int processedMask = 1;
int firstMagnitudeBitMask = 2;
int w1 = width;
int w2 = width * 2;
int w3 = width * 3;
int nextBit = 0;
for (int i0 = 0; i0 < height; i0 = nextBit) {
nextBit = Math.min(i0 + 4, height);
int indexBase = i0 * width;
boolean checkAllEmpty = (i0 + 3) < height;
for (int j = 0; j < width; j++) {
int index0 = indexBase + j;
boolean allEmpty = (checkAllEmpty
&& currentFlag[index0] == 0
&& currentFlag[index0 + w1] == 0
&& currentFlag[index0 + w2] == 0
&& currentFlag[index0 + w3] == 0
&& neighborSigns[index0] == 0
&& neighborSigns[index0 + w1] == 0
&& neighborSigns[index0 + w2] == 0
&& neighborSigns[index0 + w3] == 0);
int i1 = 0, index = index0;
int i = i0, sign;
if (allEmpty) {
int hasSignificantCoefficent = decoder.decodeBit(cx, RUNLENGTH);
if (hasSignificantCoefficent == 0) {
bitsDecoded[index0]++;
bitsDecoded[index0 + w1]++;
bitsDecoded[index0 + w2]++;
bitsDecoded[index0 + w3]++;
continue;
}
i1 = (decoder.decodeBit(cx, UNIFORM) << 1) | decoder.decodeBit(cx, UNIFORM);
if (i1 != 0) {
i = i0 + i1;
index += (i1 * width);
}
sign = decodeSignBit(i, j, index);
coefficientsSign[index] = (byte) sign;
switch (mbType) {
case BYTEMB:
((byte[]) magnitude)[index] = 1;
break;
case SHORTMB:
((short[]) magnitude)[index] = 1;
break;
case INTMB:
((int[]) magnitude)[index] = 1;
break;
}
setNeighborSigns(i, j, index);
currentFlag[index] = (byte) ((currentFlag[index] & 0xff) | firstMagnitudeBitMask);
index = index0;
for (int i2 = i0; i2 <= i; i2++) {
bitsDecoded[index]++;
index += width;
}
i1++;
}
for (i = i0 + i1; i < nextBit; i++, index += width) {
long coefIndex = 0;
switch (mbType) {
case BYTEMB:
coefIndex = ((byte[]) magnitude)[index];
break;
case SHORTMB:
coefIndex = ((short[]) magnitude)[index];
break;
case INTMB:
coefIndex = ((int[]) magnitude)[index];
break;
}
if (coefIndex != 0 || ((currentFlag[index] & 0xff) & processedMask) != 0) {
continue;
}
int contextLabel = contextLableTable[(neighborSigns[index] & 0xff)] ;
int decision = decoder.decodeBit(cx, contextLabel);
if (decision == 1) {
sign = decodeSignBit(i, j, index);
coefficientsSign[index] = (byte) sign;
switch (mbType) {
case BYTEMB:
((byte[]) magnitude)[index] = 1;
break;
case SHORTMB:
((short[]) magnitude)[index] = 1;
break;
case INTMB:
((int[]) magnitude)[index] = 1;
break;
}
setNeighborSigns(i, j, index);
currentFlag[index] = (byte) ((currentFlag[index] & 0xff) | firstMagnitudeBitMask);
}
bitsDecoded[index]++;
}
}
}
}
}
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