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notmasteryet 2012-01-13 18:45:19 -06:00
parent b89f544b18
commit ac592a2fdd
1 changed files with 41 additions and 31 deletions
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72
src/jpx.js
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@ -438,10 +438,10 @@ var JpxImage = (function JpxImageClosure() {
if (i >= height) if (i >= height)
break; break;
var contextLabel = labels[neighborsSignificance[index]]; if (coefficentsMagnitude[index] || !neighborsSignificance[index])
if (coefficentsMagnitude[index] || !contextLabel)
continue; continue;
var contextLabel = labels[neighborsSignificance[index]];
var cx = contexts[contextLabel]; var cx = contexts[contextLabel];
var decision = decoder.readBit(cx); var decision = decoder.readBit(cx);
if (decision) { if (decision) {
@ -538,18 +538,23 @@ var JpxImage = (function JpxImageClosure() {
var processingFlags = this.processingFlags; var processingFlags = this.processingFlags;
var processedMask = 1; var processedMask = 1;
var firstMagnitudeBitMask = 2; var firstMagnitudeBitMask = 2;
var oneRowDown = width;
var twoRowsDown = width * 2;
var threeRowsDown = width * 3;
for (var i0 = 0; i0 < height; i0 += 4) { for (var i0 = 0; i0 < height; i0 += 4) {
for (var j = 0; j < width; j++) { for (var j = 0; j < width; j++) {
var index0 = i0 * width + j; var index0 = i0 * width + j;
// using the property: labels[neighborsSignificance[index]] == 0
// when neighborsSignificance[index] == 0
var allEmpty = i0 + 3 < height && var allEmpty = i0 + 3 < height &&
processingFlags[index0] == 0 && processingFlags[index0] == 0 &&
processingFlags[index0 + width] == 0 && processingFlags[index0 + oneRowDown] == 0 &&
processingFlags[index0 + 2 * width] == 0 && processingFlags[index0 + twoRowsDown] == 0 &&
processingFlags[index0 + 3 * width] == 0 && processingFlags[index0 + threeRowsDown] == 0 &&
labels[neighborsSignificance[index0]] == 0 && neighborsSignificance[index0] == 0 &&
labels[neighborsSignificance[index0 + width]] == 0 && neighborsSignificance[index0 + oneRowDown] == 0 &&
labels[neighborsSignificance[index0 + 2 * width]] == 0 && neighborsSignificance[index0 + twoRowsDown] == 0 &&
labels[neighborsSignificance[index0 + 3 * width]] == 0; neighborsSignificance[index0 + threeRowsDown] == 0;
var i1 = 0, index = index0; var i1 = 0, index = index0;
var cx, i; var cx, i;
if (allEmpty) { if (allEmpty) {
@ -557,9 +562,9 @@ var JpxImage = (function JpxImageClosure() {
var hasSignificantCoefficent = decoder.readBit(cx); var hasSignificantCoefficent = decoder.readBit(cx);
if (!hasSignificantCoefficent) { if (!hasSignificantCoefficent) {
bitsDecoded[index0]++; bitsDecoded[index0]++;
bitsDecoded[index0 + width]++; bitsDecoded[index0 + oneRowDown]++;
bitsDecoded[index0 + 2 * width]++; bitsDecoded[index0 + twoRowsDown]++;
bitsDecoded[index0 + 3 * width]++; bitsDecoded[index0 + threeRowsDown]++;
continue; // next column continue; // next column
} }
cx = this.uniformContext; cx = this.uniformContext;
@ -584,11 +589,11 @@ var JpxImage = (function JpxImageClosure() {
if (i >= height) if (i >= height)
break; break;
var contextLabel = labels[neighborsSignificance[index]];
if (coefficentsMagnitude[index] || if (coefficentsMagnitude[index] ||
(processingFlags[index] & processedMask) != 0) (processingFlags[index] & processedMask) != 0)
continue; continue;
var contextLabel = labels[neighborsSignificance[index]];
cx = contexts[contextLabel]; cx = contexts[contextLabel];
var decision = decoder.readBit(cx); var decision = decoder.readBit(cx);
if (decision == 1) { if (decision == 1) {
@ -623,29 +628,34 @@ var JpxImage = (function JpxImageClosure() {
}; };
Transform.prototype.iterate = function transformIterate(ll, hl, lh, hh, Transform.prototype.iterate = function transformIterate(ll, hl, lh, hh,
u0, v0) { u0, v0) {
var llWidth = ll.width, llHeight = ll.height, llItems = ll.items;
var hlWidth = hl.width, hlHeight = hl.height, hlItems = hl.items;
var lhWidth = lh.width, lhHeight = lh.height, lhItems = lh.items;
var hhWidth = hh.width, hhHeight = hh.height, hhItems = hh.items;
// Section F.3.3 interleave // Section F.3.3 interleave
var width = ll.width + hl.width; var width = llWidth + hlWidth;
var height = ll.height + lh.height; var height = llHeight + lhHeight;
var items = new Float32Array(width * height); var items = new Float32Array(width * height);
for (var i = 0, ii = ll.height; i < ii; i++) { for (var i = 0, ii = llHeight; i < ii; i++) {
var k = i * ll.width, l = i * 2 * width; var k = i * llWidth, l = i * 2 * width;
for (var j = 0, jj = ll.width; j < jj; j++, k++, l += 2) for (var j = 0, jj = llWidth; j < jj; j++, k++, l += 2)
items[l] = ll.items[k]; items[l] = llItems[k];
} }
for (var i = 0, ii = hl.height; i < ii; i++) { for (var i = 0, ii = hlHeight; i < ii; i++) {
var k = i * hl.width, l = i * 2 * width + 1; var k = i * hlWidth, l = i * 2 * width + 1;
for (var j = 0, jj = hl.width; j < jj; j++, k++, l += 2) for (var j = 0, jj = hlWidth; j < jj; j++, k++, l += 2)
items[l] = hl.items[k]; items[l] = hlItems[k];
} }
for (var i = 0, ii = lh.height; i < ii; i++) { for (var i = 0, ii = lhHeight; i < ii; i++) {
var k = i * lh.width, l = (i * 2 + 1) * width; var k = i * lhWidth, l = (i * 2 + 1) * width;
for (var j = 0, jj = lh.width; j < jj; j++, k++, l += 2) for (var j = 0, jj = lhWidth; j < jj; j++, k++, l += 2)
items[l] = lh.items[k]; items[l] = lhItems[k];
} }
for (var i = 0, ii = hh.height; i < ii; i++) { for (var i = 0, ii = hhHeight; i < ii; i++) {
var k = i * hh.width, l = (i * 2 + 1) * width + 1; var k = i * hhWidth, l = (i * 2 + 1) * width + 1;
for (var j = 0, jj = hh.width; j < jj; j++, k++, l += 2) for (var j = 0, jj = hhWidth; j < jj; j++, k++, l += 2)
items[l] = hh.items[k]; items[l] = hhItems[k];
} }
var bufferPadding = 4; var bufferPadding = 4;