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// Version 1.0a
// Copyright (C) 1998, James R. Weeks and BioElectroMech.
// Visit BioElectroMech at www.obrador.com. Email [email protected].
// See license.txt for details about the allowed used of this software.
// This software is based in part on the work of the Independent JPEG Group.
// See IJGreadme.txt for details about the Independent JPEG Group's license.
// This encoder is inspired by the Java Jpeg encoder by Florian Raemy,
// studwww.eurecom.fr/~raemy.
// It borrows a great deal of code and structure from the Independent
// Jpeg Group's Jpeg 6a library, Copyright Thomas G. Lane.
// See license.txt for details
/*
* JpegEncoder and its associated classes are Copyright (c) 1998, James R. Weeks and BioElectroMech
* see(Jmol/src/com/obrador/license.txt)
*
* javjs.img.JpegEncoder.java was adapted by Bob Hanson
*
* for Jmol in the following ways:
*
* 1) minor coding efficiencies were made in some for() loops.
* 2) methods not used by Jmol were commented out
* 3) method and variable signatures were modified to provide
* more appropriate method privacy.
* 4) additions for Java2Script compatibility
*
* Original files are maintained in the Jmol.src.com.obrador package, but
* these original files are not distributed with Jmol.
*
*/
package javajs.img;
import java.io.IOException;
import java.util.Map;
import javajs.img.ImageEncoder;
import javajs.util.AU;
import javajs.util.OC;
/**
* JpegEncoder - The JPEG main program which performs a jpeg compression of an
* image.
*
* A system to allow the full Jmol state -- regardless of length --
* to be encoded in a set of APP1 (FFE1) tags.
* But we have to be careful about line ends for backward compatibility.
* This solution is not 100% effective, because some data lines may in principle be
* Very large and may not contain new lines for more than 65500 characters,
* But that would be very unusual. Perhaps a huge data set loaded from a
* string. Introduced in Jmol 12.1.36. Bob Hanson
*
* See org.com.obrador.license.txt
*
*/
public class JpgEncoder extends ImageEncoder {
// this string will GENERALLY appear at the end of lines and be escaped
private static final int CONTINUE_MAX = 65500; // some room to spare here.
private static final int CONTINUE_MAX_BUFFER = CONTINUE_MAX + 10; // never break up last 10 bytes
private JpegObj jpegObj;
private Huffman huf;
private DCT dct;
protected int defaultQuality = 100;
private String applicationTag;
public JpgEncoder() {
}
@Override
protected void setParams(Map params) {
if (quality <= 0)
quality = (params.containsKey("qualityJPG") ? ((Integer) params.get("qualityJPG")).intValue() : defaultQuality);
jpegObj = new JpegObj();
jpegObj.comment = (String) params.get("comment");
applicationTag = (String) params.get("jpgAppTag");
}
@Override
protected void generate() throws IOException {
jpegObj.imageWidth = width;
jpegObj.imageHeight = height;
dct = new DCT(quality);
huf = new Huffman(width, height);
if (jpegObj == null)
return;
jpegObj.getYCCArray(pixels);
String longState = writeHeaders(jpegObj, dct);
writeCompressedData(jpegObj, dct, huf);
writeMarker(eoi);
if (longState != null) {
byte[] b = longState.getBytes();
out.write(b, 0, b.length);
}
}
private void writeCompressedData(JpegObj jpegObj, DCT dct, Huffman huf) {
int i, j, r, c, a, b;
int comp, xpos, ypos, xblockoffset, yblockoffset;
float inputArray[][];
float dctArray1[][] = new float[8][8];
double dctArray2[][] = new double[8][8];
int dctArray3[] = new int[8 * 8];
/*
* This method controls the compression of the image.
* Starting at the upper left of the image, it compresses 8x8 blocks
* of data until the entire image has been compressed.
*/
int lastDCvalue[] = new int[jpegObj.numberOfComponents];
//int zeroArray[] = new int[64]; // initialized to hold all zeros
//int Width = 0, Height = 0;
//int nothing = 0, not;
int minBlockWidth, minBlockHeight;
// This initial setting of MinBlockWidth and MinBlockHeight is done to
// ensure they start with values larger than will actually be the case.
minBlockWidth = ((huf.imageWidth % 8 != 0) ? (int) (Math
.floor(huf.imageWidth / 8.0) + 1) * 8 : huf.imageWidth);
minBlockHeight = ((huf.imageHeight % 8 != 0) ? (int) (Math
.floor(huf.imageHeight / 8.0) + 1) * 8 : huf.imageHeight);
for (comp = 0; comp < jpegObj.numberOfComponents; comp++) {
minBlockWidth = Math.min(minBlockWidth, jpegObj.blockWidth[comp]);
minBlockHeight = Math.min(minBlockHeight, jpegObj.blockHeight[comp]);
}
xpos = 0;
for (r = 0; r < minBlockHeight; r++) {
for (c = 0; c < minBlockWidth; c++) {
xpos = c * 8;
ypos = r * 8;
for (comp = 0; comp < jpegObj.numberOfComponents; comp++) {
//Width = JpegObj.BlockWidth[comp];
//Height = JpegObj.BlockHeight[comp];
inputArray = jpegObj.components[comp];
int vsampF = jpegObj.vsampFactor[comp];
int hsampF = jpegObj.hsampFactor[comp];
int qNumber = jpegObj.qtableNumber[comp];
int dcNumber = jpegObj.dctableNumber[comp];
int acNumber = jpegObj.actableNumber[comp];
for (i = 0; i < vsampF; i++) {
for (j = 0; j < hsampF; j++) {
xblockoffset = j * 8;
yblockoffset = i * 8;
for (a = 0; a < 8; a++) {
for (b = 0; b < 8; b++) {
// I believe this is where the dirty line at the bottom of
// the image is coming from.
// I need to do a check here to make sure I'm not reading past
// image data.
// This seems to not be a big issue right now. (04/04/98)
dctArray1[a][b] = inputArray[ypos + yblockoffset + a][xpos
+ xblockoffset + b];
}
}
// The following code commented out because on some images this technique
// results in poor right and bottom borders.
// if ((!JpegObj.lastColumnIsDummy[comp] || c < Width - 1) &&
// (!JpegObj.lastRowIsDummy[comp] || r < Height - 1)) {
dctArray2 = DCT.forwardDCT(dctArray1);
dctArray3 = DCT.quantizeBlock(dctArray2, dct.divisors[qNumber]);
// }
// else {
// zeroArray[0] = dctArray3[0];
// zeroArray[0] = lastDCvalue[comp];
// dctArray3 = zeroArray;
// }
huf.HuffmanBlockEncoder(out, dctArray3, lastDCvalue[comp],
dcNumber, acNumber);
lastDCvalue[comp] = dctArray3[0];
}
}
}
}
}
huf.flushBuffer(out);
}
private static byte[] eoi = { (byte) 0xFF, (byte) 0xD9 };
private static byte[] jfif = new byte[] {
/* JFIF[0] =*/(byte) 0xff,
/* JFIF[1] =*/(byte) 0xe0,
/* JFIF[2] =*/0,
/* JFIF[3] =*/16,
/* JFIF[4] =*/(byte) 0x4a, //'J'
/* JFIF[5] =*/(byte) 0x46, //'F'
/* JFIF[6] =*/(byte) 0x49, //'I'
/* JFIF[7] =*/(byte) 0x46, //'F'
/* JFIF[8] =*/0,
/* JFIF[9] =*/1,
/* JFIF[10] =*/0,
/* JFIF[11] =*/0,
/* JFIF[12] =*/0,
/* JFIF[13] =*/1,
/* JFIF[14] =*/0,
/* JFIF[15] =*/1,
/* JFIF[16] =*/0,
/* JFIF[17] =*/0 };
private static byte[] soi = { (byte) 0xFF, (byte) 0xD8 };
private String writeHeaders(JpegObj jpegObj, DCT dct) {
int i, j, index, offset;
int tempArray[];
// the SOI marker
writeMarker(soi);
// The order of the following headers is quite inconsequential.
// the JFIF header
writeArray(jfif);
// Comment Header
String comment = null;
if (jpegObj.comment.length() > 0)
writeString(jpegObj.comment, (byte) 0xE1); // App data 1
writeString(
"JPEG Encoder Copyright 1998, James R. Weeks and BioElectroMech.\n\n",
(byte) 0xFE);
// The DQT header
// 0 is the luminance index and 1 is the chrominance index
byte dqt[] = new byte[134];
dqt[0] = (byte) 0xFF;
dqt[1] = (byte) 0xDB;
dqt[2] = 0;
dqt[3] = (byte) 132;
offset = 4;
for (i = 0; i < 2; i++) {
dqt[offset++] = (byte) ((0 << 4) + i);
tempArray = dct.quantum[i];
for (j = 0; j < 64; j++) {
dqt[offset++] = (byte) tempArray[Huffman.jpegNaturalOrder[j]];
}
}
writeArray(dqt);
// Start of Frame Header
byte sof[] = new byte[19];
sof[0] = (byte) 0xFF;
sof[1] = (byte) 0xC0;
sof[2] = 0;
sof[3] = 17;
sof[4] = (byte) jpegObj.precision;
sof[5] = (byte) ((jpegObj.imageHeight >> 8) & 0xFF);
sof[6] = (byte) ((jpegObj.imageHeight) & 0xFF);
sof[7] = (byte) ((jpegObj.imageWidth >> 8) & 0xFF);
sof[8] = (byte) ((jpegObj.imageWidth) & 0xFF);
sof[9] = (byte) jpegObj.numberOfComponents;
index = 10;
for (i = 0; i < sof[9]; i++) {
sof[index++] = (byte) jpegObj.compID[i];
sof[index++] = (byte) ((jpegObj.hsampFactor[i] << 4) + jpegObj.vsampFactor[i]);
sof[index++] = (byte) jpegObj.qtableNumber[i];
}
writeArray(sof);
WriteDHTHeader(Huffman.bitsDCluminance, Huffman.valDCluminance);
WriteDHTHeader(Huffman.bitsACluminance, Huffman.valACluminance);
WriteDHTHeader(Huffman.bitsDCchrominance, Huffman.valDCchrominance);
WriteDHTHeader(Huffman.bitsACchrominance, Huffman.valACchrominance);
// Start of Scan Header
byte sos[] = new byte[14];
sos[0] = (byte) 0xFF;
sos[1] = (byte) 0xDA;
sos[2] = 0;
sos[3] = 12;
sos[4] = (byte) jpegObj.numberOfComponents;
index = 5;
for (i = 0; i < sos[4]; i++) {
sos[index++] = (byte) jpegObj.compID[i];
sos[index++] = (byte) ((jpegObj.dctableNumber[i] << 4) + jpegObj.actableNumber[i]);
}
sos[index++] = (byte) jpegObj.ss;
sos[index++] = (byte) jpegObj.se;
sos[index++] = (byte) ((jpegObj.ah << 4) + jpegObj.al);
writeArray(sos);
return comment;
}
private void writeString(String s, byte id) {
int len = s.length();
int i0 = 0;
String suffix = applicationTag;
while (i0 < len) {
int nBytes = len - i0;
if (nBytes > CONTINUE_MAX_BUFFER) {
nBytes = CONTINUE_MAX;
// but break only at line breaks
int pt = s.lastIndexOf('\n', i0 + nBytes);
if (pt > i0 + 1)
nBytes = pt - i0;
}
if (i0 + nBytes == len)
suffix = "";
writeTag(nBytes + suffix.length(), id);
writeArray(s.substring(i0, i0 + nBytes).getBytes());
if (suffix.length() > 0)
writeArray(suffix.getBytes());
i0 += nBytes;
}
}
private void writeTag(int length, byte id) {
length += 2;
byte com[] = new byte[4];
com[0] = (byte) 0xFF;
com[1] = id;
com[2] = (byte) ((length >> 8) & 0xFF);
com[3] = (byte) (length & 0xFF);
writeArray(com);
}
void WriteDHTHeader(int[] bits, int[] val) {
// [email protected]: simplified code.
byte[] dht;
int bytes = 0;
for (int j = 1; j < 17; j++)
bytes += bits[j];
dht = new byte[21 + bytes];
dht[0] = (byte) 0xFF;
dht[1] = (byte) 0xC4;
int index = 4;
for (int j = 0; j < 17; j++)
dht[index++] = (byte) bits[j];
for (int j = 0; j < bytes; j++)
dht[index++] = (byte) val[j];
dht[2] = (byte) (((index - 2) >> 8) & 0xFF);
dht[3] = (byte) ((index - 2) & 0xFF);
writeArray(dht);
}
void writeMarker(byte[] data) {
out.write(data, 0, 2);
}
void writeArray(byte[] data) {
out.write(data, 0, data.length);
}
}
// This class incorporates quality scaling as implemented in the JPEG-6a
// library.
/*
* DCT - A Java implementation of the Discreet Cosine Transform
*/
class DCT {
/**
* DCT Block Size - default 8
*/
private final static int N = 8;
private final static int NN = N * N;
/**
* Image Quality (0-100) - default 80 (good image / good compression)
*/
//public int QUALITY = 80;
int[][] quantum = AU.newInt2(2);
double[][] divisors = AU.newDouble2(2);
/**
* Quantitization Matrix for luminace.
*/
private int quantum_luminance[] = new int[NN];
private double DivisorsLuminance[] = new double[NN];
/**
* Quantitization Matrix for chrominance.
*/
private int quantum_chrominance[] = new int[NN];
private double DivisorsChrominance[] = new double[NN];
/**
* Constructs a new DCT object. Initializes the cosine transform matrix these
* are used when computing the DCT and it's inverse. This also initializes the
* run length counters and the ZigZag sequence. Note that the image quality
* can be worse than 25 however the image will be extemely pixelated, usually
* to a block size of N.
*
* @param quality
* The quality of the image (0 worst - 100 best)
*
*/
DCT(int quality) {
initMatrix(quality);
}
/*
* This method sets up the quantization matrix for luminance and
* chrominance using the Quality parameter.
*/
private void initMatrix(int quality) {
// converting quality setting to that specified in the jpeg_quality_scaling
// method in the IJG Jpeg-6a C libraries
quality = (quality < 1 ? 1 : quality > 100 ? 100 : quality);
quality = (quality < 50 ? 5000 / quality : 200 - quality * 2);
// Creating the luminance matrix
quantum_luminance[0] = 16;
quantum_luminance[1] = 11;
quantum_luminance[2] = 10;
quantum_luminance[3] = 16;
quantum_luminance[4] = 24;
quantum_luminance[5] = 40;
quantum_luminance[6] = 51;
quantum_luminance[7] = 61;
quantum_luminance[8] = 12;
quantum_luminance[9] = 12;
quantum_luminance[10] = 14;
quantum_luminance[11] = 19;
quantum_luminance[12] = 26;
quantum_luminance[13] = 58;
quantum_luminance[14] = 60;
quantum_luminance[15] = 55;
quantum_luminance[16] = 14;
quantum_luminance[17] = 13;
quantum_luminance[18] = 16;
quantum_luminance[19] = 24;
quantum_luminance[20] = 40;
quantum_luminance[21] = 57;
quantum_luminance[22] = 69;
quantum_luminance[23] = 56;
quantum_luminance[24] = 14;
quantum_luminance[25] = 17;
quantum_luminance[26] = 22;
quantum_luminance[27] = 29;
quantum_luminance[28] = 51;
quantum_luminance[29] = 87;
quantum_luminance[30] = 80;
quantum_luminance[31] = 62;
quantum_luminance[32] = 18;
quantum_luminance[33] = 22;
quantum_luminance[34] = 37;
quantum_luminance[35] = 56;
quantum_luminance[36] = 68;
quantum_luminance[37] = 109;
quantum_luminance[38] = 103;
quantum_luminance[39] = 77;
quantum_luminance[40] = 24;
quantum_luminance[41] = 35;
quantum_luminance[42] = 55;
quantum_luminance[43] = 64;
quantum_luminance[44] = 81;
quantum_luminance[45] = 104;
quantum_luminance[46] = 113;
quantum_luminance[47] = 92;
quantum_luminance[48] = 49;
quantum_luminance[49] = 64;
quantum_luminance[50] = 78;
quantum_luminance[51] = 87;
quantum_luminance[52] = 103;
quantum_luminance[53] = 121;
quantum_luminance[54] = 120;
quantum_luminance[55] = 101;
quantum_luminance[56] = 72;
quantum_luminance[57] = 92;
quantum_luminance[58] = 95;
quantum_luminance[59] = 98;
quantum_luminance[60] = 112;
quantum_luminance[61] = 100;
quantum_luminance[62] = 103;
quantum_luminance[63] = 99;
AANscale(DivisorsLuminance, quantum_luminance, quality);
// Creating the chrominance matrix
for (int i = 4; i < 64; i++)
quantum_chrominance[i] = 99;
quantum_chrominance[0] = 17;
quantum_chrominance[1] = 18;
quantum_chrominance[2] = 24;
quantum_chrominance[3] = 47;
quantum_chrominance[8] = 18;
quantum_chrominance[9] = 21;
quantum_chrominance[10] = 26;
quantum_chrominance[11] = 66;
quantum_chrominance[16] = 24;
quantum_chrominance[17] = 26;
quantum_chrominance[18] = 56;
quantum_chrominance[24] = 47;
quantum_chrominance[25] = 66;
AANscale(DivisorsChrominance, quantum_chrominance, quality);
// quantum and Divisors are objects used to hold the appropriate matices
quantum[0] = quantum_luminance;
quantum[1] = quantum_chrominance;
divisors[0] = DivisorsLuminance;
divisors[1] = DivisorsChrominance;
}
private final static double[] AANscaleFactor = { 1.0, 1.387039845,
1.306562965, 1.175875602, 1.0, 0.785694958, 0.541196100, 0.275899379 };
static private void AANscale(double[] divisors, int[] values, int quality) {
for (int j = 0; j < 64; j++) {
int temp = (values[j] * quality + 50) / 100;
values[j] = (temp < 1 ? 1 : temp > 255 ? 255 : temp);
}
for (int i = 0, index = 0; i < 8; i++)
for (int j = 0; j < 8; j++, index++)
// The divisors for the LL&M method (the slow integer method used in
// jpeg 6a library). This method is currently (04/04/98) incompletely
// implemented.
// DivisorsLuminance[index] = ((double) quantum_luminance[index]) << 3;
// The divisors for the AAN method (the float method used in jpeg 6a library.
divisors[index] = (0.125 / (values[index] * AANscaleFactor[i] * AANscaleFactor[j]));
}
/*
* This method preforms forward DCT on a block of image data using
* the literal method specified for a 2-D Discrete Cosine Transform.
* It is included as a curiosity and can give you an idea of the
* difference in the compression result (the resulting image quality)
* by comparing its output to the output of the AAN method below.
* It is ridiculously inefficient.
*/
// For now the final output is unusable. The associated quantization step
// needs some tweaking. If you get this part working, please let me know.
/*
public double[][] forwardDCTExtreme(float input[][])
{
double output[][] = new double[N][N];
int v, u, x, y;
for (v = 0; v < 8; v++) {
for (u = 0; u < 8; u++) {
for (x = 0; x < 8; x++) {
for (y = 0; y < 8; y++) {
output[v][u] += input[x][y] *
Math.cos(((double)(2*x + 1)*(double)u*Math.PI)/16)*
Math.cos(((double)(2*y + 1)*(double)v*Math.PI)/16);
}
}
output[v][u] *= (0.25)*((u == 0) ? (1.0/Math.sqrt(2)) : (double) 1.0)*((v == 0) ? (1.0/Math.sqrt(2)) : (double) 1.0);
}
}
return output;
}
*/
/*
* This method preforms a DCT on a block of image data using the AAN
* method as implemented in the IJG Jpeg-6a library.
*/
static double[][] forwardDCT(float input[][]) {
double output[][] = new double[N][N];
double tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
double tmp10, tmp11, tmp12, tmp13;
double z1, z2, z3, z4, z5, z11, z13;
// Subtracts 128 from the input values
for (int i = 0; i < 8; i++)
for (int j = 0; j < 8; j++)
output[i][j] = (input[i][j] - 128.0);
// input[i][j] -= 128;
for (int i = 0; i < 8; i++) {
tmp0 = output[i][0] + output[i][7];
tmp7 = output[i][0] - output[i][7];
tmp1 = output[i][1] + output[i][6];
tmp6 = output[i][1] - output[i][6];
tmp2 = output[i][2] + output[i][5];
tmp5 = output[i][2] - output[i][5];
tmp3 = output[i][3] + output[i][4];
tmp4 = output[i][3] - output[i][4];
tmp10 = tmp0 + tmp3;
tmp13 = tmp0 - tmp3;
tmp11 = tmp1 + tmp2;
tmp12 = tmp1 - tmp2;
output[i][0] = tmp10 + tmp11;
output[i][4] = tmp10 - tmp11;
z1 = (tmp12 + tmp13) * 0.707106781;
output[i][2] = tmp13 + z1;
output[i][6] = tmp13 - z1;
tmp10 = tmp4 + tmp5;
tmp11 = tmp5 + tmp6;
tmp12 = tmp6 + tmp7;
z5 = (tmp10 - tmp12) * 0.382683433;
z2 = 0.541196100 * tmp10 + z5;
z4 = 1.306562965 * tmp12 + z5;
z3 = tmp11 * 0.707106781;
z11 = tmp7 + z3;
z13 = tmp7 - z3;
output[i][5] = z13 + z2;
output[i][3] = z13 - z2;
output[i][1] = z11 + z4;
output[i][7] = z11 - z4;
}
for (int i = 0; i < 8; i++) {
tmp0 = output[0][i] + output[7][i];
tmp7 = output[0][i] - output[7][i];
tmp1 = output[1][i] + output[6][i];
tmp6 = output[1][i] - output[6][i];
tmp2 = output[2][i] + output[5][i];
tmp5 = output[2][i] - output[5][i];
tmp3 = output[3][i] + output[4][i];
tmp4 = output[3][i] - output[4][i];
tmp10 = tmp0 + tmp3;
tmp13 = tmp0 - tmp3;
tmp11 = tmp1 + tmp2;
tmp12 = tmp1 - tmp2;
output[0][i] = tmp10 + tmp11;
output[4][i] = tmp10 - tmp11;
z1 = (tmp12 + tmp13) * 0.707106781;
output[2][i] = tmp13 + z1;
output[6][i] = tmp13 - z1;
tmp10 = tmp4 + tmp5;
tmp11 = tmp5 + tmp6;
tmp12 = tmp6 + tmp7;
z5 = (tmp10 - tmp12) * 0.382683433;
z2 = 0.541196100 * tmp10 + z5;
z4 = 1.306562965 * tmp12 + z5;
z3 = tmp11 * 0.707106781;
z11 = tmp7 + z3;
z13 = tmp7 - z3;
output[5][i] = z13 + z2;
output[3][i] = z13 - z2;
output[1][i] = z11 + z4;
output[7][i] = z11 - z4;
}
return output;
}
/*
* This method quantitizes data and rounds it to the nearest integer.
*/
static int[] quantizeBlock(double inputData[][], double[] divisorsCode) {
int outputData[] = new int[NN];
for (int i = 0, index = 0; i < 8; i++)
for (int j = 0; j < 8; j++, index++)
// The second line results in significantly better compression.
outputData[index] = (int) (Math.round(inputData[i][j]
* divisorsCode[index]));
// outputData[index] = (int)(((inputData[i][j] * (((double[]) (Divisors[code]))[index])) + 16384.5) -16384);
return outputData;
}
/*
* This is the method for quantizing a block DCT'ed with forwardDCTExtreme
* This method quantitizes data and rounds it to the nearest integer.
*/
/*
public double[][] forwardDCTExtreme(float input[][])
{
double output[][] = new double[N][N];
int v, u, x, y;
for (v = 0; v < 8; v++) {
for (u = 0; u < 8; u++) {
for (x = 0; x < 8; x++) {
for (y = 0; y < 8; y++) {
output[v][u] += input[x][y] *
Math.cos(((double)(2*x + 1)*(double)u*Math.PI)/16)*
Math.cos(((double)(2*y + 1)*(double)v*Math.PI)/16);
}
}
output[v][u] *= (0.25)*((u == 0) ? (1.0/Math.sqrt(2)) : (double) 1.0)*((v == 0) ? (1.0/Math.sqrt(2)) : (double) 1.0);
}
}
return output;
}
*/
/*
public int[] quantizeBlockExtreme(double inputData[][], int code)
{
int outputData[] = new int[NN];
int i, j;
int index;
index = 0;
for (i = 0; i < 8; i++) {
for (j = 0; j < 8; j++) {
outputData[index] = (int)(Math.round(inputData[i][j] / (((int[]) (quantum[code]))[index])));
index++;
}
}
return outputData;
}
*/
}
// This class was modified by James R. Weeks on 3/27/98.
// It now incorporates Huffman table derivation as in the C jpeg library
// from the IJG, Jpeg-6a.
class Huffman {
private int bufferPutBits, bufferPutBuffer;
int imageHeight;
int imageWidth;
private int dc_matrix0[][];
private int ac_matrix0[][];
private int dc_matrix1[][];
private int ac_matrix1[][];
private int[][][] dc_matrix;
private int[][][] ac_matrix;
//private int code;
int numOfDCTables;
int numOfACTables;
final static int[] bitsDCluminance = { 0x00, 0, 1, 5, 1, 1, 1, 1, 1, 1, 0, 0,
0, 0, 0, 0, 0 };
final static int[] valDCluminance = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 };
final static int[] bitsDCchrominance = { 0x01, 0, 3, 1, 1, 1, 1, 1, 1, 1, 1,
1, 0, 0, 0, 0, 0 };
final static int[] valDCchrominance = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 };
final static int[] bitsACluminance = { 0x10, 0, 2, 1, 3, 3, 2, 4, 3, 5, 5, 4,
4, 0, 0, 1, 0x7d };
final static int[] valACluminance = { 0x01, 0x02, 0x03, 0x00, 0x04, 0x11,
0x05, 0x12, 0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07, 0x22, 0x71,
0x14, 0x32, 0x81, 0x91, 0xa1, 0x08, 0x23, 0x42, 0xb1, 0xc1, 0x15, 0x52,
0xd1, 0xf0, 0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0a, 0x16, 0x17, 0x18,
0x19, 0x1a, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x34, 0x35, 0x36, 0x37,
0x38, 0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4a, 0x53,
0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67,
0x68, 0x69, 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0x83,
0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96,
0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, 0xa8, 0xa9,
0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3,
0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6,
0xd7, 0xd8, 0xd9, 0xda, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8,
0xe9, 0xea, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa };
final static int[] bitsACchrominance = { 0x11, 0, 2, 1, 2, 4, 4, 3, 4, 7, 5,
4, 4, 0, 1, 2, 0x77 };
final static int[] valACchrominance = { 0x00, 0x01, 0x02, 0x03, 0x11, 0x04,
0x05, 0x21, 0x31, 0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71, 0x13, 0x22,
0x32, 0x81, 0x08, 0x14, 0x42, 0x91, 0xa1, 0xb1, 0xc1, 0x09, 0x23, 0x33,
0x52, 0xf0, 0x15, 0x62, 0x72, 0xd1, 0x0a, 0x16, 0x24, 0x34, 0xe1, 0x25,
0xf1, 0x17, 0x18, 0x19, 0x1a, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x35, 0x36,
0x37, 0x38, 0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4a,
0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a, 0x63, 0x64, 0x65, 0x66,
0x67, 0x68, 0x69, 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a,
0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a, 0x92, 0x93, 0x94,
0x95, 0x96, 0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba,
0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4,
0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7,
0xe8, 0xe9, 0xea, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa };
/*
* jpegNaturalOrder[i] is the natural-order position of the i'th element
* of zigzag order.
*/
final static int[] jpegNaturalOrder = { 0, 1, 8, 16, 9, 2, 3, 10, 17, 24, 32,
25, 18, 11, 4, 5, 12, 19, 26, 33, 40, 48, 41, 34, 27, 20, 13, 6, 7, 14,
21, 28, 35, 42, 49, 56, 57, 50, 43, 36, 29, 22, 15, 23, 30, 37, 44, 51,
58, 59, 52, 45, 38, 31, 39, 46, 53, 60, 61, 54, 47, 55, 62, 63, };
Huffman(int width, int height) {
initHuf();
imageWidth = width;
imageHeight = height;
}
/**
* HuffmanBlockEncoder run length encodes and Huffman encodes the quantized
* data.
*
* @param out
* @param zigzag
* @param prec
* @param dcCode
* @param acCode
**/
void HuffmanBlockEncoder(OC out, int zigzag[], int prec,
int dcCode, int acCode) {
int temp, temp2, nbits, k, r, i;
numOfDCTables = 2;
numOfACTables = 2;
int[][] matrixDC = dc_matrix[dcCode];
int[][] matrixAC = ac_matrix[acCode];
// The DC portion
temp = temp2 = zigzag[0] - prec;
if (temp < 0) {
temp = -temp;
temp2--;
}
nbits = 0;
while (temp != 0) {
nbits++;
temp >>= 1;
}
// if (nbits > 11) nbits = 11;
bufferIt(out, matrixDC[nbits][0], matrixDC[nbits][1]);
// The arguments in bufferIt are code and size.
if (nbits != 0) {
bufferIt(out, temp2, nbits);
}
// The AC portion
r = 0;
for (k = 1; k < 64; k++) {
if ((temp = zigzag[jpegNaturalOrder[k]]) == 0) {
r++;
} else {
while (r > 15) {
bufferIt(out, matrixAC[0xF0][0], matrixAC[0xF0][1]);
r -= 16;
}
temp2 = temp;
if (temp < 0) {
temp = -temp;
temp2--;
}
nbits = 1;
while ((temp >>= 1) != 0) {
nbits++;
}
i = (r << 4) + nbits;
bufferIt(out, matrixAC[i][0], matrixAC[i][1]);
bufferIt(out, temp2, nbits);
r = 0;
}
}
if (r > 0) {
bufferIt(out, matrixAC[0][0], matrixAC[0][1]);
}
}
// Uses an integer long (32 bits) buffer to store the Huffman encoded bits
// and sends them to out by the byte.
void bufferIt(OC out, int code, int size) {
int putBuffer = code;
int putBits = bufferPutBits;
putBuffer &= (1 << size) - 1;
putBits += size;
putBuffer <<= 24 - putBits;
putBuffer |= bufferPutBuffer;
while (putBits >= 8) {
int c = ((putBuffer >> 16) & 0xFF);
out.writeByteAsInt(c);
if (c == 0xFF) {
out.writeByteAsInt(0);
}
putBuffer <<= 8;
putBits -= 8;
}
bufferPutBuffer = putBuffer;
bufferPutBits = putBits;
}
void flushBuffer(OC out) {
int putBuffer = bufferPutBuffer;
int putBits = bufferPutBits;
while (putBits >= 8) {
int c = ((putBuffer >> 16) & 0xFF);
out.writeByteAsInt(c);
if (c == 0xFF) {
out.writeByteAsInt(0);
}
putBuffer <<= 8;
putBits -= 8;
}
if (putBits > 0) {
int c = ((putBuffer >> 16) & 0xFF);
out.writeByteAsInt(c);
}
}
/*
* Initialisation of the Huffman codes for Luminance and Chrominance.
* This code results in the same tables created in the IJG Jpeg-6a
* library.
*/
private void initHuf() {
dc_matrix0 = new int[12][2];
dc_matrix1 = new int[12][2];
ac_matrix0 = new int[255][2];
ac_matrix1 = new int[255][2];
dc_matrix = AU.newInt3(2, -1);
ac_matrix = AU.newInt3(2, -1);
int p, l, i, lastp, si, code;
int[] huffsize = new int[257];
int[] huffcode = new int[257];
/*
* init of the DC values for the chrominance
* [][0] is the code [][1] is the number of bit
*/
p = 0;
for (l = 1; l <= 16; l++) {
// for (i = 1; i <= bitsDCchrominance[l]; i++)
for (i = bitsDCchrominance[l]; --i >= 0;) {
huffsize[p++] = l; //that's an "el", not a "one"
}
}
huffsize[p] = 0;
lastp = p;
code = 0;
si = huffsize[0];
p = 0;
while (huffsize[p] != 0) {
while (huffsize[p] == si) {
huffcode[p++] = code;
code++;
}
code <<= 1;
si++;
}
for (p = 0; p < lastp; p++) {
dc_matrix1[valDCchrominance[p]][0] = huffcode[p];
dc_matrix1[valDCchrominance[p]][1] = huffsize[p];
}
/*
* Init of the AC huffman code for the chrominance
* matrix [][][0] is the code & matrix[][][1] is the number of bit needed
*/
p = 0;
for (l = 1; l <= 16; l++) {
for (i = bitsACchrominance[l]; --i >= 0;)
// for (i = 1; i <= bitsACchrominance[l]; i++)
{
huffsize[p++] = l;
}
}
huffsize[p] = 0;
lastp = p;
code = 0;
si = huffsize[0];
p = 0;
while (huffsize[p] != 0) {
while (huffsize[p] == si) {
huffcode[p++] = code;
code++;
}
code <<= 1;
si++;
}
for (p = 0; p < lastp; p++) {
ac_matrix1[valACchrominance[p]][0] = huffcode[p];
ac_matrix1[valACchrominance[p]][1] = huffsize[p];
}
/*
* init of the DC values for the luminance
* [][0] is the code [][1] is the number of bit
*/
p = 0;
for (l = 1; l <= 16; l++) {
// for (i = 1; i <= bitsDCluminance[l]; i++)
for (i = bitsDCluminance[l]; --i >= 0;) {
huffsize[p++] = l;
}
}
huffsize[p] = 0;
lastp = p;
code = 0;
si = huffsize[0];
p = 0;
while (huffsize[p] != 0) {
while (huffsize[p] == si) {
huffcode[p++] = code;
code++;
}
code <<= 1;
si++;
}
for (p = 0; p < lastp; p++) {
dc_matrix0[valDCluminance[p]][0] = huffcode[p];
dc_matrix0[valDCluminance[p]][1] = huffsize[p];
}
/*
* Init of the AC huffman code for luminance
* matrix [][][0] is the code & matrix[][][1] is the number of bit
*/
p = 0;
for (l = 1; l <= 16; l++) {
// for (i = 1; i <= bitsACluminance[l]; i++)
for (i = bitsACluminance[l]; --i >= 0;) {
huffsize[p++] = l;
}
}
huffsize[p] = 0;
lastp = p;
code = 0;
si = huffsize[0];
p = 0;
while (huffsize[p] != 0) {
while (huffsize[p] == si) {
huffcode[p++] = code;
code++;
}
code <<= 1;
si++;
}
for (int q = 0; q < lastp; q++) {
ac_matrix0[valACluminance[q]][0] = huffcode[q];
ac_matrix0[valACluminance[q]][1] = huffsize[q];
}
dc_matrix[0] = dc_matrix0;
dc_matrix[1] = dc_matrix1;
ac_matrix[0] = ac_matrix0;
ac_matrix[1] = ac_matrix1;
}
}
/*
* JpegInfo - Given an image, sets default information about it and divides
* it into its constituant components, downsizing those that need to be.
*/
class JpegObj {
String comment;
int imageHeight;
int imageWidth;
int blockWidth[];
int blockHeight[];
int precision = 8;
int numberOfComponents = 3;
float[][][] components;
int[] compID = { 1, 2, 3 };
int[] hsampFactor = { 1, 1, 1 };
int[] vsampFactor = { 1, 1, 1 };
int[] qtableNumber = { 0, 1, 1 };
int[] dctableNumber = { 0, 1, 1 };
int[] actableNumber = { 0, 1, 1 };
private boolean[] lastColumnIsDummy = { false, false, false };
private boolean[] lastRowIsDummy = { false, false, false };
int ss = 0;
int se = 63;
int ah = 0;
int al = 0;
private int compWidth[];
private int compHeight[];
private int maxHsampFactor;
private int maxVsampFactor;
public JpegObj() {
components = AU.newFloat3(numberOfComponents, -1);
compWidth = new int[numberOfComponents];
compHeight = new int[numberOfComponents];
blockWidth = new int[numberOfComponents];
blockHeight = new int[numberOfComponents];
}
/*
* This method creates and fills three arrays, Y, Cb, and Cr using the
* input image.
*/
void getYCCArray(int[] pixels) {
// In order to minimize the chance that grabPixels will throw an exception
// it may be necessary to grab some pixels every few scanlines and process
// those before going for more. The time expense may be prohibitive.
// However, for a situation where memory overhead is a concern, this may be
// the only choice.
maxHsampFactor = 1;
maxVsampFactor = 1;
for (int y = 0; y < numberOfComponents; y++) {
maxHsampFactor = Math.max(maxHsampFactor, hsampFactor[y]);
maxVsampFactor = Math.max(maxVsampFactor, vsampFactor[y]);
}
for (int y = 0; y < numberOfComponents; y++) {
compWidth[y] = (((imageWidth % 8 != 0) ? ((int) Math
.ceil(imageWidth / 8.0)) * 8 : imageWidth) / maxHsampFactor)
* hsampFactor[y];
if (compWidth[y] != ((imageWidth / maxHsampFactor) * hsampFactor[y])) {
lastColumnIsDummy[y] = true;
}
// results in a multiple of 8 for compWidth
// this will make the rest of the program fail for the unlikely
// event that someone tries to compress an 16 x 16 pixel image
// which would of course be worse than pointless
blockWidth[y] = (int) Math.ceil(compWidth[y] / 8.0);
compHeight[y] = (((imageHeight % 8 != 0) ? ((int) Math
.ceil(imageHeight / 8.0)) * 8 : imageHeight) / maxVsampFactor)
* vsampFactor[y];
if (compHeight[y] != ((imageHeight / maxVsampFactor) * vsampFactor[y])) {
lastRowIsDummy[y] = true;
}
blockHeight[y] = (int) Math.ceil(compHeight[y] / 8.0);
}
float Y[][] = new float[compHeight[0]][compWidth[0]];
float Cr1[][] = new float[compHeight[0]][compWidth[0]];
float Cb1[][] = new float[compHeight[0]][compWidth[0]];
//float Cb2[][] = new float[compHeight[1]][compWidth[1]];
//float Cr2[][] = new float[compHeight[2]][compWidth[2]];
for (int pt = 0, y = 0; y < imageHeight; ++y) {
for (int x = 0; x < imageWidth; ++x, pt++) {
int p = pixels[pt];
int r = ((p >> 16) & 0xff);
int g = ((p >> 8) & 0xff);
int b = (p & 0xff);
// The following three lines are a more correct color conversion but
// the current conversion technique is sufficient and results in a higher
// compression rate.
// Y[y][x] = 16 + (float)(0.8588*(0.299 * (float)r + 0.587 * (float)g + 0.114 * (float)b ));
// Cb1[y][x] = 128 + (float)(0.8784*(-0.16874 * (float)r - 0.33126 * (float)g + 0.5 * (float)b));
// Cr1[y][x] = 128 + (float)(0.8784*(0.5 * (float)r - 0.41869 * (float)g - 0.08131 * (float)b));
Y[y][x] = (float) ((0.299 * r + 0.587 * g + 0.114 * b));
Cb1[y][x] = 128 + (float) ((-0.16874 * r - 0.33126 * g + 0.5 * b));
Cr1[y][x] = 128 + (float) ((0.5 * r - 0.41869 * g - 0.08131 * b));
}
}
// Need a way to set the H and V sample factors before allowing downsampling.
// For now (04/04/98) downsampling must be hard coded.
// Until a better downsampler is implemented, this will not be done.
// Downsampling is currently supported. The downsampling method here
// is a simple box filter.
components[0] = Y;
// Cb2 = DownSample(Cb1, 1);
components[1] = Cb1;
// Cr2 = DownSample(Cr1, 2);
components[2] = Cr1;
}
/*
float[][] DownSample(float[][] C, int comp)
{
int inrow, incol;
int outrow, outcol;
float output[][];
int bias;
inrow = 0;
incol = 0;
int cHeight = compHeight[comp];
int cWidth = compWidth[comp];
output = new float[cHeight][cWidth];
for (outrow = 0; outrow < cHeight; outrow++) {
bias = 1;
for (outcol = 0; outcol < cWidth; outcol++) {
output[outrow][outcol] = (C[inrow][incol++] + C[inrow++][incol--]
+ C[inrow][incol++] + C[inrow--][incol++] + bias)/(float)4.0;
bias ^= 3;
}
inrow += 2;
incol = 0;
}
return output;
}
*/
}