2021-09-01 16:11:55 +03:00
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class Image {
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2021-12-02 10:28:09 +03:00
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getPixel(x, y) {
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const index = x + y * this.width;
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2021-01-25 15:15:42 +03:00
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const rntVal = {
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r: this.data[index * 4],
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g: this.data[index * 4 + 1],
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b: this.data[index * 4 + 2],
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a: this.data[index * 4 + 3]
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};
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return rntVal;
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}
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2021-12-02 10:28:09 +03:00
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setPixel(x, y, pix) {
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const index = x + y * this.width;
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2021-01-25 15:15:42 +03:00
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this.data[index * 4] = pix.r;
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this.data[index * 4 + 1] = pix.g;
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this.data[index * 4 + 2] = pix.b;
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this.data[index * 4 + 3] = pix.a;
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}
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}
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2021-01-22 12:39:57 +03:00
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const JpegImage = function jpegImage() {
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"use strict";
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const dctZigZag = new Int32Array([
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0,
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1,
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8,
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16,
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9,
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2,
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3,
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10,
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17,
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24,
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32,
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25,
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18,
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11,
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4,
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5,
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12,
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19,
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26,
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33,
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40,
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48,
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41,
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34,
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27,
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20,
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13,
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6,
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7,
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14,
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21,
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28,
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35,
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42,
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49,
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56,
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57,
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50,
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43,
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36,
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29,
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22,
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15,
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23,
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30,
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37,
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44,
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51,
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58,
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59,
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52,
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45,
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38,
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31,
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39,
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46,
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53,
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60,
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61,
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54,
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47,
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55,
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62,
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63
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]);
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const dctCos1 = 4017;
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const dctSin1 = 799;
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const dctCos3 = 3406;
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const dctSin3 = 2276;
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const dctCos6 = 1567;
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const dctSin6 = 3784;
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const dctSqrt2 = 5793;
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const dctSqrt1d2 = 2896;
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function constructor() {
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}
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function buildHuffmanTable(codeLengths, values) {
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let k = 0;
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const code = [];
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let i, j, length = 16;
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while(length > 0 && !codeLengths[length - 1]){
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length--;
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}
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code.push({
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children: [],
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index: 0
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});
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let p = code[0], q;
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for(i = 0; i < length; i++){
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for(j = 0; j < codeLengths[i]; j++){
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p = code.pop();
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p.children[p.index] = values[k];
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while(p.index > 0){
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p = code.pop();
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}
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p.index++;
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code.push(p);
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while(code.length <= i){
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code.push(q = {
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children: [],
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index: 0
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});
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p.children[p.index] = q.children;
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p = q;
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}
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k++;
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}
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if (i + 1 < length) {
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code.push(q = {
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children: [],
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index: 0
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});
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p.children[p.index] = q.children;
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p = q;
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}
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}
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return code[0].children;
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}
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function decodeScan(data, offset, frame, components, resetInterval, spectralStart, spectralEnd, successivePrev, successive) {
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const mcusPerLine = frame.mcusPerLine;
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const progressive = frame.progressive;
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const startOffset = offset;
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let bitsData = 0, bitsCount = 0;
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function readBit() {
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if (bitsCount > 0) {
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bitsCount--;
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return bitsData >> bitsCount & 1;
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}
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bitsData = data[offset++];
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if (bitsData === 255) {
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const nextByte = data[offset++];
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if (nextByte) {
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throw new Error("unexpected marker: " + (bitsData << 8 | nextByte).toString(16));
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}
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}
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bitsCount = 7;
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return bitsData >>> 7;
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}
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function decodeHuffman(tree) {
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let node = tree, bit;
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while((bit = readBit()) !== null){
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node = node[bit];
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if (typeof node === "number") {
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return node;
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}
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if (typeof node !== "object") {
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throw new Error("invalid huffman sequence");
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}
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}
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return null;
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}
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function receive(length) {
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let n = 0;
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while(length > 0){
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const bit = readBit();
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if (bit === null) {
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return;
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}
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n = n << 1 | bit;
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length--;
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}
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return n;
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}
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function receiveAndExtend(length) {
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const n = receive(length);
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if (n >= 1 << length - 1) {
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return n;
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}
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return n + (-1 << length) + 1;
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}
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function decodeBaseline(component, zz) {
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const t = decodeHuffman(component.huffmanTableDC);
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const diff = t === 0 ? 0 : receiveAndExtend(t);
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zz[0] = component.pred += diff;
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let k = 1;
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while(k < 64){
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const rs = decodeHuffman(component.huffmanTableAC);
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const s = rs & 15, r = rs >> 4;
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if (s === 0) {
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if (r < 15) {
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break;
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}
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k += 16;
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continue;
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}
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k += r;
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const z = dctZigZag[k];
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zz[z] = receiveAndExtend(s);
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k++;
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}
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}
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function decodeDCFirst(component, zz) {
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const t = decodeHuffman(component.huffmanTableDC);
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const diff = t === 0 ? 0 : receiveAndExtend(t) << successive;
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zz[0] = component.pred += diff;
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}
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function decodeDCSuccessive(component, zz) {
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zz[0] |= readBit() << successive;
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}
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let eobrun = 0;
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function decodeACFirst(component, zz) {
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if (eobrun > 0) {
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eobrun--;
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return;
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}
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let k = spectralStart, e = spectralEnd;
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while(k <= e){
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const rs = decodeHuffman(component.huffmanTableAC);
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const s = rs & 15, r = rs >> 4;
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if (s === 0) {
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if (r < 15) {
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eobrun = receive(r) + (1 << r) - 1;
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break;
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}
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k += 16;
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continue;
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}
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k += r;
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const z = dctZigZag[k];
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zz[z] = receiveAndExtend(s) * (1 << successive);
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k++;
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}
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}
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let successiveACState = 0, successiveACNextValue;
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function decodeACSuccessive(component, zz) {
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let k = spectralStart, e = spectralEnd, r = 0;
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while(k <= e){
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const z = dctZigZag[k];
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const direction = zz[z] < 0 ? -1 : 1;
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switch(successiveACState){
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case 0:
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const rs = decodeHuffman(component.huffmanTableAC);
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const s = rs & 15;
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r = rs >> 4;
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if (s === 0) {
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if (r < 15) {
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eobrun = receive(r) + (1 << r);
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successiveACState = 4;
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} else {
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r = 16;
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successiveACState = 1;
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}
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} else {
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if (s !== 1) {
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throw new Error("invalid ACn encoding");
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}
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successiveACNextValue = receiveAndExtend(s);
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successiveACState = r ? 2 : 3;
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}
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continue;
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case 1:
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case 2:
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if (zz[z]) {
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zz[z] += (readBit() << successive) * direction;
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} else {
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r--;
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if (r === 0) {
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successiveACState = successiveACState == 2 ? 3 : 0;
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}
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}
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break;
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case 3:
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if (zz[z]) {
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zz[z] += (readBit() << successive) * direction;
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} else {
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zz[z] = successiveACNextValue << successive;
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successiveACState = 0;
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}
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break;
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case 4:
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if (zz[z]) {
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zz[z] += (readBit() << successive) * direction;
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}
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break;
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}
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k++;
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}
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if (successiveACState === 4) {
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eobrun--;
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if (eobrun === 0) {
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successiveACState = 0;
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}
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}
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}
|
2021-12-03 19:55:27 +03:00
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function decodeMcu(component, decode1, mcu, row, col) {
|
2021-01-22 12:39:57 +03:00
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const mcuRow = mcu / mcusPerLine | 0;
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const mcuCol = mcu % mcusPerLine;
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const blockRow = mcuRow * component.v + row;
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const blockCol = mcuCol * component.h + col;
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2021-12-03 19:55:27 +03:00
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decode1(component, component.blocks[blockRow][blockCol]);
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2021-01-22 12:39:57 +03:00
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}
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2021-12-03 19:55:27 +03:00
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function decodeBlock(component, decode2, mcu) {
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2021-01-22 12:39:57 +03:00
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const blockRow = mcu / component.blocksPerLine | 0;
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const blockCol = mcu % component.blocksPerLine;
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2021-12-03 19:55:27 +03:00
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decode2(component, component.blocks[blockRow][blockCol]);
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2021-01-22 12:39:57 +03:00
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}
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const componentsLength = components.length;
|
2021-10-21 08:12:50 +03:00
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let component1, i, j, k1, n1;
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2021-01-22 12:39:57 +03:00
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let decodeFn;
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if (progressive) {
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if (spectralStart === 0) {
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decodeFn = successivePrev === 0 ? decodeDCFirst : decodeDCSuccessive;
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} else {
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decodeFn = successivePrev === 0 ? decodeACFirst : decodeACSuccessive;
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}
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} else {
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decodeFn = decodeBaseline;
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}
|
2021-10-21 08:12:50 +03:00
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|
|
let mcu1 = 0, marker;
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2021-01-22 12:39:57 +03:00
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|
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let mcuExpected;
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if (componentsLength == 1) {
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mcuExpected = components[0].blocksPerLine * components[0].blocksPerColumn;
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} else {
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mcuExpected = mcusPerLine * frame.mcusPerColumn;
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}
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if (!resetInterval) {
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resetInterval = mcuExpected;
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}
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let h, v;
|
2021-10-21 08:12:50 +03:00
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|
|
while(mcu1 < mcuExpected){
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2021-01-22 12:39:57 +03:00
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|
|
for(i = 0; i < componentsLength; i++){
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|
components[i].pred = 0;
|
|
|
|
|
}
|
|
|
|
|
eobrun = 0;
|
|
|
|
|
if (componentsLength == 1) {
|
2021-10-21 08:12:50 +03:00
|
|
|
component1 = components[0];
|
|
|
|
|
for(n1 = 0; n1 < resetInterval; n1++){
|
|
|
|
|
decodeBlock(component1, decodeFn, mcu1);
|
|
|
|
|
mcu1++;
|
2021-01-22 12:39:57 +03:00
|
|
|
}
|
|
|
|
|
} else {
|
2021-10-21 08:12:50 +03:00
|
|
|
for(n1 = 0; n1 < resetInterval; n1++){
|
2021-01-22 12:39:57 +03:00
|
|
|
for(i = 0; i < componentsLength; i++){
|
2021-10-21 08:12:50 +03:00
|
|
|
component1 = components[i];
|
|
|
|
|
h = component1.h;
|
|
|
|
|
v = component1.v;
|
2021-01-22 12:39:57 +03:00
|
|
|
for(j = 0; j < v; j++){
|
2021-10-21 08:12:50 +03:00
|
|
|
for(k1 = 0; k1 < h; k1++){
|
|
|
|
|
decodeMcu(component1, decodeFn, mcu1, j, k1);
|
2021-01-22 12:39:57 +03:00
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
}
|
2021-10-21 08:12:50 +03:00
|
|
|
mcu1++;
|
|
|
|
|
if (mcu1 === mcuExpected) {
|
2021-01-22 12:39:57 +03:00
|
|
|
break;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
bitsCount = 0;
|
|
|
|
|
marker = data[offset] << 8 | data[offset + 1];
|
|
|
|
|
if (marker < 65280) {
|
|
|
|
|
throw new Error("marker was not found");
|
|
|
|
|
}
|
|
|
|
|
if (marker >= 65488 && marker <= 65495) {
|
|
|
|
|
offset += 2;
|
|
|
|
|
} else {
|
|
|
|
|
break;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
return offset - startOffset;
|
|
|
|
|
}
|
|
|
|
|
function buildComponentData(frame, component) {
|
|
|
|
|
const lines = [];
|
|
|
|
|
const blocksPerLine = component.blocksPerLine;
|
|
|
|
|
const blocksPerColumn = component.blocksPerColumn;
|
|
|
|
|
const samplesPerLine = blocksPerLine << 3;
|
|
|
|
|
const R = new Int32Array(64), r = new Uint8Array(64);
|
|
|
|
|
function quantizeAndInverse(zz, dataOut, dataIn) {
|
|
|
|
|
const qt = component.quantizationTable;
|
|
|
|
|
let v0, v1, v2, v3, v4, v5, v6, v7, t;
|
|
|
|
|
const p = dataIn;
|
|
|
|
|
let i;
|
|
|
|
|
for(i = 0; i < 64; i++){
|
|
|
|
|
p[i] = zz[i] * qt[i];
|
|
|
|
|
}
|
|
|
|
|
for(i = 0; i < 8; ++i){
|
|
|
|
|
const row = 8 * i;
|
|
|
|
|
if (p[1 + row] == 0 && p[2 + row] == 0 && p[3 + row] == 0 && p[4 + row] == 0 && p[5 + row] == 0 && p[6 + row] == 0 && p[7 + row] == 0) {
|
|
|
|
|
t = dctSqrt2 * p[0 + row] + 512 >> 10;
|
|
|
|
|
p[0 + row] = t;
|
|
|
|
|
p[1 + row] = t;
|
|
|
|
|
p[2 + row] = t;
|
|
|
|
|
p[3 + row] = t;
|
|
|
|
|
p[4 + row] = t;
|
|
|
|
|
p[5 + row] = t;
|
|
|
|
|
p[6 + row] = t;
|
|
|
|
|
p[7 + row] = t;
|
|
|
|
|
continue;
|
|
|
|
|
}
|
|
|
|
|
v0 = dctSqrt2 * p[0 + row] + 128 >> 8;
|
|
|
|
|
v1 = dctSqrt2 * p[4 + row] + 128 >> 8;
|
|
|
|
|
v2 = p[2 + row];
|
|
|
|
|
v3 = p[6 + row];
|
|
|
|
|
v4 = dctSqrt1d2 * (p[1 + row] - p[7 + row]) + 128 >> 8;
|
|
|
|
|
v7 = dctSqrt1d2 * (p[1 + row] + p[7 + row]) + 128 >> 8;
|
|
|
|
|
v5 = p[3 + row] << 4;
|
|
|
|
|
v6 = p[5 + row] << 4;
|
|
|
|
|
t = v0 - v1 + 1 >> 1;
|
|
|
|
|
v0 = v0 + v1 + 1 >> 1;
|
|
|
|
|
v1 = t;
|
|
|
|
|
t = v2 * dctSin6 + v3 * dctCos6 + 128 >> 8;
|
|
|
|
|
v2 = v2 * dctCos6 - v3 * dctSin6 + 128 >> 8;
|
|
|
|
|
v3 = t;
|
|
|
|
|
t = v4 - v6 + 1 >> 1;
|
|
|
|
|
v4 = v4 + v6 + 1 >> 1;
|
|
|
|
|
v6 = t;
|
|
|
|
|
t = v7 + v5 + 1 >> 1;
|
|
|
|
|
v5 = v7 - v5 + 1 >> 1;
|
|
|
|
|
v7 = t;
|
|
|
|
|
t = v0 - v3 + 1 >> 1;
|
|
|
|
|
v0 = v0 + v3 + 1 >> 1;
|
|
|
|
|
v3 = t;
|
|
|
|
|
t = v1 - v2 + 1 >> 1;
|
|
|
|
|
v1 = v1 + v2 + 1 >> 1;
|
|
|
|
|
v2 = t;
|
|
|
|
|
t = v4 * dctSin3 + v7 * dctCos3 + 2048 >> 12;
|
|
|
|
|
v4 = v4 * dctCos3 - v7 * dctSin3 + 2048 >> 12;
|
|
|
|
|
v7 = t;
|
|
|
|
|
t = v5 * dctSin1 + v6 * dctCos1 + 2048 >> 12;
|
|
|
|
|
v5 = v5 * dctCos1 - v6 * dctSin1 + 2048 >> 12;
|
|
|
|
|
v6 = t;
|
|
|
|
|
p[0 + row] = v0 + v7;
|
|
|
|
|
p[7 + row] = v0 - v7;
|
|
|
|
|
p[1 + row] = v1 + v6;
|
|
|
|
|
p[6 + row] = v1 - v6;
|
|
|
|
|
p[2 + row] = v2 + v5;
|
|
|
|
|
p[5 + row] = v2 - v5;
|
|
|
|
|
p[3 + row] = v3 + v4;
|
|
|
|
|
p[4 + row] = v3 - v4;
|
|
|
|
|
}
|
|
|
|
|
for(i = 0; i < 8; ++i){
|
|
|
|
|
const col = i;
|
|
|
|
|
if (p[1 * 8 + col] == 0 && p[2 * 8 + col] == 0 && p[3 * 8 + col] == 0 && p[4 * 8 + col] == 0 && p[5 * 8 + col] == 0 && p[6 * 8 + col] == 0 && p[7 * 8 + col] == 0) {
|
|
|
|
|
t = dctSqrt2 * dataIn[i + 0] + 8192 >> 14;
|
|
|
|
|
p[0 * 8 + col] = t;
|
|
|
|
|
p[1 * 8 + col] = t;
|
|
|
|
|
p[2 * 8 + col] = t;
|
|
|
|
|
p[3 * 8 + col] = t;
|
|
|
|
|
p[4 * 8 + col] = t;
|
|
|
|
|
p[5 * 8 + col] = t;
|
|
|
|
|
p[6 * 8 + col] = t;
|
|
|
|
|
p[7 * 8 + col] = t;
|
|
|
|
|
continue;
|
|
|
|
|
}
|
|
|
|
|
v0 = dctSqrt2 * p[0 * 8 + col] + 2048 >> 12;
|
|
|
|
|
v1 = dctSqrt2 * p[4 * 8 + col] + 2048 >> 12;
|
|
|
|
|
v2 = p[2 * 8 + col];
|
|
|
|
|
v3 = p[6 * 8 + col];
|
|
|
|
|
v4 = dctSqrt1d2 * (p[1 * 8 + col] - p[7 * 8 + col]) + 2048 >> 12;
|
|
|
|
|
v7 = dctSqrt1d2 * (p[1 * 8 + col] + p[7 * 8 + col]) + 2048 >> 12;
|
|
|
|
|
v5 = p[3 * 8 + col];
|
|
|
|
|
v6 = p[5 * 8 + col];
|
|
|
|
|
t = v0 - v1 + 1 >> 1;
|
|
|
|
|
v0 = v0 + v1 + 1 >> 1;
|
|
|
|
|
v1 = t;
|
|
|
|
|
t = v2 * dctSin6 + v3 * dctCos6 + 2048 >> 12;
|
|
|
|
|
v2 = v2 * dctCos6 - v3 * dctSin6 + 2048 >> 12;
|
|
|
|
|
v3 = t;
|
|
|
|
|
t = v4 - v6 + 1 >> 1;
|
|
|
|
|
v4 = v4 + v6 + 1 >> 1;
|
|
|
|
|
v6 = t;
|
|
|
|
|
t = v7 + v5 + 1 >> 1;
|
|
|
|
|
v5 = v7 - v5 + 1 >> 1;
|
|
|
|
|
v7 = t;
|
|
|
|
|
t = v0 - v3 + 1 >> 1;
|
|
|
|
|
v0 = v0 + v3 + 1 >> 1;
|
|
|
|
|
v3 = t;
|
|
|
|
|
t = v1 - v2 + 1 >> 1;
|
|
|
|
|
v1 = v1 + v2 + 1 >> 1;
|
|
|
|
|
v2 = t;
|
|
|
|
|
t = v4 * dctSin3 + v7 * dctCos3 + 2048 >> 12;
|
|
|
|
|
v4 = v4 * dctCos3 - v7 * dctSin3 + 2048 >> 12;
|
|
|
|
|
v7 = t;
|
|
|
|
|
t = v5 * dctSin1 + v6 * dctCos1 + 2048 >> 12;
|
|
|
|
|
v5 = v5 * dctCos1 - v6 * dctSin1 + 2048 >> 12;
|
|
|
|
|
v6 = t;
|
|
|
|
|
p[0 * 8 + col] = v0 + v7;
|
|
|
|
|
p[7 * 8 + col] = v0 - v7;
|
|
|
|
|
p[1 * 8 + col] = v1 + v6;
|
|
|
|
|
p[6 * 8 + col] = v1 - v6;
|
|
|
|
|
p[2 * 8 + col] = v2 + v5;
|
|
|
|
|
p[5 * 8 + col] = v2 - v5;
|
|
|
|
|
p[3 * 8 + col] = v3 + v4;
|
|
|
|
|
p[4 * 8 + col] = v3 - v4;
|
|
|
|
|
}
|
|
|
|
|
for(i = 0; i < 64; ++i){
|
|
|
|
|
const sample = 128 + (p[i] + 8 >> 4);
|
|
|
|
|
dataOut[i] = sample < 0 ? 0 : sample > 255 ? 255 : sample;
|
|
|
|
|
}
|
|
|
|
|
}
|
2021-10-21 08:12:50 +03:00
|
|
|
let i1, j;
|
2021-01-22 12:39:57 +03:00
|
|
|
for(let blockRow = 0; blockRow < blocksPerColumn; blockRow++){
|
|
|
|
|
const scanLine = blockRow << 3;
|
2021-10-21 08:12:50 +03:00
|
|
|
for(i1 = 0; i1 < 8; i1++){
|
2021-01-22 12:39:57 +03:00
|
|
|
lines.push(new Uint8Array(samplesPerLine));
|
|
|
|
|
}
|
|
|
|
|
for(let blockCol = 0; blockCol < blocksPerLine; blockCol++){
|
|
|
|
|
quantizeAndInverse(component.blocks[blockRow][blockCol], r, R);
|
|
|
|
|
let offset = 0, sample = blockCol << 3;
|
|
|
|
|
for(j = 0; j < 8; j++){
|
|
|
|
|
const line = lines[scanLine + j];
|
2021-10-21 08:12:50 +03:00
|
|
|
for(i1 = 0; i1 < 8; i1++){
|
|
|
|
|
line[sample + i1] = r[offset++];
|
2021-01-22 12:39:57 +03:00
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
return lines;
|
|
|
|
|
}
|
|
|
|
|
function clampTo8bit(a) {
|
|
|
|
|
return a < 0 ? 0 : a > 255 ? 255 : a;
|
|
|
|
|
}
|
|
|
|
|
constructor.prototype = {
|
|
|
|
|
load: function load(path) {
|
|
|
|
|
},
|
|
|
|
|
parse: function parse(data) {
|
|
|
|
|
let offset = 0;
|
|
|
|
|
function readUint16() {
|
|
|
|
|
const value = data[offset] << 8 | data[offset + 1];
|
|
|
|
|
offset += 2;
|
|
|
|
|
return value;
|
|
|
|
|
}
|
|
|
|
|
function readDataBlock() {
|
|
|
|
|
const length = readUint16();
|
|
|
|
|
const array = data.subarray(offset, offset + length - 2);
|
|
|
|
|
offset += array.length;
|
|
|
|
|
return array;
|
|
|
|
|
}
|
|
|
|
|
function prepareComponents(frame) {
|
|
|
|
|
let maxH = 0, maxV = 0;
|
|
|
|
|
let component, componentId;
|
|
|
|
|
for(componentId in frame.components){
|
|
|
|
|
if (frame.components.hasOwnProperty(componentId)) {
|
|
|
|
|
component = frame.components[componentId];
|
|
|
|
|
if (maxH < component.h) {
|
|
|
|
|
maxH = component.h;
|
|
|
|
|
}
|
|
|
|
|
if (maxV < component.v) {
|
|
|
|
|
maxV = component.v;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
const mcusPerLine = Math.ceil(frame.samplesPerLine / 8 / maxH);
|
|
|
|
|
const mcusPerColumn = Math.ceil(frame.scanLines / 8 / maxV);
|
|
|
|
|
for(componentId in frame.components){
|
|
|
|
|
if (frame.components.hasOwnProperty(componentId)) {
|
|
|
|
|
component = frame.components[componentId];
|
|
|
|
|
const blocksPerLine = Math.ceil(Math.ceil(frame.samplesPerLine / 8) * component.h / maxH);
|
|
|
|
|
const blocksPerColumn = Math.ceil(Math.ceil(frame.scanLines / 8) * component.v / maxV);
|
|
|
|
|
const blocksPerLineForMcu = mcusPerLine * component.h;
|
|
|
|
|
const blocksPerColumnForMcu = mcusPerColumn * component.v;
|
|
|
|
|
const blocks = [];
|
|
|
|
|
for(let i = 0; i < blocksPerColumnForMcu; i++){
|
|
|
|
|
const row = [];
|
|
|
|
|
for(let j = 0; j < blocksPerLineForMcu; j++){
|
|
|
|
|
row.push(new Int32Array(64));
|
|
|
|
|
}
|
|
|
|
|
blocks.push(row);
|
|
|
|
|
}
|
|
|
|
|
component.blocksPerLine = blocksPerLine;
|
|
|
|
|
component.blocksPerColumn = blocksPerColumn;
|
|
|
|
|
component.blocks = blocks;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
frame.maxH = maxH;
|
|
|
|
|
frame.maxV = maxV;
|
|
|
|
|
frame.mcusPerLine = mcusPerLine;
|
|
|
|
|
frame.mcusPerColumn = mcusPerColumn;
|
|
|
|
|
}
|
|
|
|
|
let jfif = null;
|
|
|
|
|
let adobe = null;
|
2021-10-21 08:12:50 +03:00
|
|
|
let frame1, resetInterval;
|
2021-01-22 12:39:57 +03:00
|
|
|
const quantizationTables = [], frames = [];
|
|
|
|
|
const huffmanTablesAC = [], huffmanTablesDC = [];
|
|
|
|
|
let fileMarker = readUint16();
|
|
|
|
|
if (fileMarker != 65496) {
|
|
|
|
|
throw new Error("SOI not found");
|
|
|
|
|
}
|
|
|
|
|
fileMarker = readUint16();
|
|
|
|
|
while(fileMarker != 65497){
|
2021-10-08 10:47:01 +03:00
|
|
|
let i, j;
|
2021-01-22 12:39:57 +03:00
|
|
|
switch(fileMarker){
|
2021-10-08 10:47:01 +03:00
|
|
|
case 65280:
|
|
|
|
|
break;
|
2021-01-22 12:39:57 +03:00
|
|
|
case 65504:
|
|
|
|
|
case 65505:
|
|
|
|
|
case 65506:
|
|
|
|
|
case 65507:
|
|
|
|
|
case 65508:
|
|
|
|
|
case 65509:
|
|
|
|
|
case 65510:
|
|
|
|
|
case 65511:
|
|
|
|
|
case 65512:
|
|
|
|
|
case 65513:
|
|
|
|
|
case 65514:
|
|
|
|
|
case 65515:
|
|
|
|
|
case 65516:
|
|
|
|
|
case 65517:
|
|
|
|
|
case 65518:
|
|
|
|
|
case 65519:
|
|
|
|
|
case 65534:
|
|
|
|
|
const appData = readDataBlock();
|
|
|
|
|
if (fileMarker === 65504) {
|
|
|
|
|
if (appData[0] === 74 && appData[1] === 70 && appData[2] === 73 && appData[3] === 70 && appData[4] === 0) {
|
|
|
|
|
jfif = {
|
|
|
|
|
version: {
|
|
|
|
|
major: appData[5],
|
|
|
|
|
minor: appData[6]
|
|
|
|
|
},
|
|
|
|
|
densityUnits: appData[7],
|
|
|
|
|
xDensity: appData[8] << 8 | appData[9],
|
|
|
|
|
yDensity: appData[10] << 8 | appData[11],
|
|
|
|
|
thumbWidth: appData[12],
|
|
|
|
|
thumbHeight: appData[13],
|
|
|
|
|
thumbData: appData.subarray(14, 14 + 3 * appData[12] * appData[13])
|
|
|
|
|
};
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
if (fileMarker === 65518) {
|
|
|
|
|
if (appData[0] === 65 && appData[1] === 100 && appData[2] === 111 && appData[3] === 98 && appData[4] === 101 && appData[5] === 0) {
|
|
|
|
|
adobe = {
|
|
|
|
|
version: appData[6],
|
|
|
|
|
flags0: appData[7] << 8 | appData[8],
|
|
|
|
|
flags1: appData[9] << 8 | appData[10],
|
|
|
|
|
transformCode: appData[11]
|
|
|
|
|
};
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
break;
|
|
|
|
|
case 65499:
|
|
|
|
|
const quantizationTablesLength = readUint16();
|
|
|
|
|
const quantizationTablesEnd = quantizationTablesLength + offset - 2;
|
|
|
|
|
while(offset < quantizationTablesEnd){
|
|
|
|
|
const quantizationTableSpec = data[offset++];
|
|
|
|
|
const tableData = new Int32Array(64);
|
|
|
|
|
if (quantizationTableSpec >> 4 === 0) {
|
|
|
|
|
for(j = 0; j < 64; j++){
|
|
|
|
|
const z = dctZigZag[j];
|
|
|
|
|
tableData[z] = data[offset++];
|
|
|
|
|
}
|
|
|
|
|
} else if (quantizationTableSpec >> 4 === 1) {
|
|
|
|
|
for(j = 0; j < 64; j++){
|
|
|
|
|
const z = dctZigZag[j];
|
|
|
|
|
tableData[z] = readUint16();
|
|
|
|
|
}
|
|
|
|
|
} else {
|
|
|
|
|
throw new Error("DQT: invalid table spec");
|
|
|
|
|
}
|
|
|
|
|
quantizationTables[quantizationTableSpec & 15] = tableData;
|
|
|
|
|
}
|
|
|
|
|
break;
|
|
|
|
|
case 65472:
|
|
|
|
|
case 65473:
|
|
|
|
|
case 65474:
|
|
|
|
|
readUint16();
|
2021-10-21 08:12:50 +03:00
|
|
|
frame1 = {
|
2021-01-22 12:39:57 +03:00
|
|
|
};
|
2021-10-21 08:12:50 +03:00
|
|
|
frame1.extended = fileMarker === 65473;
|
|
|
|
|
frame1.progressive = fileMarker === 65474;
|
|
|
|
|
frame1.precision = data[offset++];
|
|
|
|
|
frame1.scanLines = readUint16();
|
|
|
|
|
frame1.samplesPerLine = readUint16();
|
|
|
|
|
frame1.components = {
|
2021-01-22 12:39:57 +03:00
|
|
|
};
|
2021-10-21 08:12:50 +03:00
|
|
|
frame1.componentsOrder = [];
|
2021-01-22 12:39:57 +03:00
|
|
|
let componentsCount = data[offset++], componentId;
|
|
|
|
|
for(i = 0; i < componentsCount; i++){
|
|
|
|
|
componentId = data[offset];
|
|
|
|
|
const h = data[offset + 1] >> 4;
|
|
|
|
|
const v = data[offset + 1] & 15;
|
|
|
|
|
const qId = data[offset + 2];
|
2021-10-21 08:12:50 +03:00
|
|
|
frame1.componentsOrder.push(componentId);
|
|
|
|
|
frame1.components[componentId] = {
|
2021-01-22 12:39:57 +03:00
|
|
|
h: h,
|
|
|
|
|
v: v,
|
|
|
|
|
quantizationIdx: qId
|
|
|
|
|
};
|
|
|
|
|
offset += 3;
|
|
|
|
|
}
|
2021-10-21 08:12:50 +03:00
|
|
|
prepareComponents(frame1);
|
|
|
|
|
frames.push(frame1);
|
2021-01-22 12:39:57 +03:00
|
|
|
break;
|
|
|
|
|
case 65476:
|
|
|
|
|
const huffmanLength = readUint16();
|
|
|
|
|
for(i = 2; i < huffmanLength;){
|
|
|
|
|
const huffmanTableSpec = data[offset++];
|
|
|
|
|
const codeLengths = new Uint8Array(16);
|
|
|
|
|
let codeLengthSum = 0;
|
|
|
|
|
for(j = 0; j < 16; j++, offset++){
|
|
|
|
|
codeLengthSum += codeLengths[j] = data[offset];
|
|
|
|
|
}
|
|
|
|
|
const huffmanValues = new Uint8Array(codeLengthSum);
|
|
|
|
|
for(j = 0; j < codeLengthSum; j++, offset++){
|
|
|
|
|
huffmanValues[j] = data[offset];
|
|
|
|
|
}
|
|
|
|
|
i += 17 + codeLengthSum;
|
|
|
|
|
(huffmanTableSpec >> 4 === 0 ? huffmanTablesDC : huffmanTablesAC)[huffmanTableSpec & 15] = buildHuffmanTable(codeLengths, huffmanValues);
|
|
|
|
|
}
|
|
|
|
|
break;
|
|
|
|
|
case 65501:
|
|
|
|
|
readUint16();
|
|
|
|
|
resetInterval = readUint16();
|
|
|
|
|
break;
|
|
|
|
|
case 65498:
|
|
|
|
|
readUint16();
|
|
|
|
|
const selectorsCount = data[offset++];
|
|
|
|
|
let components = [], component;
|
|
|
|
|
for(i = 0; i < selectorsCount; i++){
|
2021-10-21 08:12:50 +03:00
|
|
|
component = frame1.components[data[offset++]];
|
2021-01-22 12:39:57 +03:00
|
|
|
const tableSpec = data[offset++];
|
|
|
|
|
component.huffmanTableDC = huffmanTablesDC[tableSpec >> 4];
|
|
|
|
|
component.huffmanTableAC = huffmanTablesAC[tableSpec & 15];
|
|
|
|
|
components.push(component);
|
|
|
|
|
}
|
|
|
|
|
const spectralStart = data[offset++];
|
|
|
|
|
const spectralEnd = data[offset++];
|
|
|
|
|
const successiveApproximation = data[offset++];
|
2021-10-21 08:12:50 +03:00
|
|
|
const processed = decodeScan(data, offset, frame1, components, resetInterval, spectralStart, spectralEnd, successiveApproximation >> 4, successiveApproximation & 15);
|
2021-01-22 12:39:57 +03:00
|
|
|
offset += processed;
|
|
|
|
|
break;
|
|
|
|
|
case 65535:
|
|
|
|
|
if (data[offset] !== 255) {
|
|
|
|
|
offset--;
|
|
|
|
|
}
|
|
|
|
|
break;
|
|
|
|
|
default:
|
|
|
|
|
if (data[offset - 3] == 255 && data[offset - 2] >= 192 && data[offset - 2] <= 254) {
|
|
|
|
|
offset -= 3;
|
|
|
|
|
break;
|
|
|
|
|
}
|
|
|
|
|
throw new Error("unknown JPEG marker " + fileMarker.toString(16));
|
|
|
|
|
}
|
|
|
|
|
fileMarker = readUint16();
|
|
|
|
|
}
|
|
|
|
|
if (frames.length != 1) {
|
|
|
|
|
throw new Error("only single frame JPEGs supported");
|
|
|
|
|
}
|
2021-10-21 08:12:50 +03:00
|
|
|
for(let i3 = 0; i3 < frames.length; i3++){
|
|
|
|
|
const cp = frames[i3].components;
|
2021-01-22 12:39:57 +03:00
|
|
|
for(const j in cp){
|
|
|
|
|
cp[j].quantizationTable = quantizationTables[cp[j].quantizationIdx];
|
|
|
|
|
delete cp[j].quantizationIdx;
|
|
|
|
|
}
|
|
|
|
|
}
|
2021-10-21 08:12:50 +03:00
|
|
|
this.width = frame1.samplesPerLine;
|
|
|
|
|
this.height = frame1.scanLines;
|
2021-01-22 12:39:57 +03:00
|
|
|
this.jfif = jfif;
|
|
|
|
|
this.adobe = adobe;
|
|
|
|
|
this.components = [];
|
2021-10-21 08:12:50 +03:00
|
|
|
for(let i2 = 0; i2 < frame1.componentsOrder.length; i2++){
|
|
|
|
|
const component = frame1.components[frame1.componentsOrder[i2]];
|
2021-01-22 12:39:57 +03:00
|
|
|
this.components.push({
|
2021-10-21 08:12:50 +03:00
|
|
|
lines: buildComponentData(frame1, component),
|
|
|
|
|
scaleX: component.h / frame1.maxH,
|
|
|
|
|
scaleY: component.v / frame1.maxV
|
2021-01-22 12:39:57 +03:00
|
|
|
});
|
|
|
|
|
}
|
|
|
|
|
},
|
|
|
|
|
getData: function getData(width, height) {
|
|
|
|
|
const scaleX = this.width / width, scaleY = this.height / height;
|
|
|
|
|
let component1, component2, component3, component4;
|
|
|
|
|
let component1Line, component2Line, component3Line, component4Line;
|
|
|
|
|
let x, y;
|
|
|
|
|
let offset = 0;
|
|
|
|
|
let Y, Cb, Cr, K, C, M, Ye, R, G, B;
|
|
|
|
|
let colorTransform;
|
|
|
|
|
const dataLength = width * height * this.components.length;
|
|
|
|
|
const data = new Uint8Array(dataLength);
|
|
|
|
|
switch(this.components.length){
|
|
|
|
|
case 1:
|
|
|
|
|
component1 = this.components[0];
|
|
|
|
|
for(y = 0; y < height; y++){
|
|
|
|
|
component1Line = component1.lines[0 | y * component1.scaleY * scaleY];
|
|
|
|
|
for(x = 0; x < width; x++){
|
|
|
|
|
Y = component1Line[0 | x * component1.scaleX * scaleX];
|
|
|
|
|
data[offset++] = Y;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
break;
|
|
|
|
|
case 2:
|
|
|
|
|
component1 = this.components[0];
|
|
|
|
|
component2 = this.components[1];
|
|
|
|
|
for(y = 0; y < height; y++){
|
|
|
|
|
component1Line = component1.lines[0 | y * component1.scaleY * scaleY];
|
|
|
|
|
component2Line = component2.lines[0 | y * component2.scaleY * scaleY];
|
|
|
|
|
for(x = 0; x < width; x++){
|
|
|
|
|
Y = component1Line[0 | x * component1.scaleX * scaleX];
|
|
|
|
|
data[offset++] = Y;
|
|
|
|
|
Y = component2Line[0 | x * component2.scaleX * scaleX];
|
|
|
|
|
data[offset++] = Y;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
break;
|
|
|
|
|
case 3:
|
|
|
|
|
colorTransform = true;
|
|
|
|
|
if (this.adobe && this.adobe.transformCode) {
|
|
|
|
|
colorTransform = true;
|
|
|
|
|
} else if (typeof this.colorTransform !== "undefined") {
|
|
|
|
|
colorTransform = !!this.colorTransform;
|
|
|
|
|
}
|
|
|
|
|
component1 = this.components[0];
|
|
|
|
|
component2 = this.components[1];
|
|
|
|
|
component3 = this.components[2];
|
|
|
|
|
for(y = 0; y < height; y++){
|
|
|
|
|
component1Line = component1.lines[0 | y * component1.scaleY * scaleY];
|
|
|
|
|
component2Line = component2.lines[0 | y * component2.scaleY * scaleY];
|
|
|
|
|
component3Line = component3.lines[0 | y * component3.scaleY * scaleY];
|
|
|
|
|
for(x = 0; x < width; x++){
|
|
|
|
|
if (!colorTransform) {
|
|
|
|
|
R = component1Line[0 | x * component1.scaleX * scaleX];
|
|
|
|
|
G = component2Line[0 | x * component2.scaleX * scaleX];
|
|
|
|
|
B = component3Line[0 | x * component3.scaleX * scaleX];
|
|
|
|
|
} else {
|
|
|
|
|
Y = component1Line[0 | x * component1.scaleX * scaleX];
|
|
|
|
|
Cb = component2Line[0 | x * component2.scaleX * scaleX];
|
|
|
|
|
Cr = component3Line[0 | x * component3.scaleX * scaleX];
|
|
|
|
|
R = clampTo8bit(Y + 1.402 * (Cr - 128));
|
|
|
|
|
G = clampTo8bit(Y - 0.3441363 * (Cb - 128) - 0.71413636 * (Cr - 128));
|
|
|
|
|
B = clampTo8bit(Y + 1.772 * (Cb - 128));
|
|
|
|
|
}
|
|
|
|
|
data[offset++] = R;
|
|
|
|
|
data[offset++] = G;
|
|
|
|
|
data[offset++] = B;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
break;
|
|
|
|
|
case 4:
|
|
|
|
|
if (!this.adobe) {
|
|
|
|
|
throw new Error("Unsupported color mode (4 components)");
|
|
|
|
|
}
|
|
|
|
|
colorTransform = false;
|
|
|
|
|
if (this.adobe && this.adobe.transformCode) {
|
|
|
|
|
colorTransform = true;
|
|
|
|
|
} else if (typeof this.colorTransform !== "undefined") {
|
|
|
|
|
colorTransform = !!this.colorTransform;
|
|
|
|
|
}
|
|
|
|
|
component1 = this.components[0];
|
|
|
|
|
component2 = this.components[1];
|
|
|
|
|
component3 = this.components[2];
|
|
|
|
|
component4 = this.components[3];
|
|
|
|
|
for(y = 0; y < height; y++){
|
|
|
|
|
component1Line = component1.lines[0 | y * component1.scaleY * scaleY];
|
|
|
|
|
component2Line = component2.lines[0 | y * component2.scaleY * scaleY];
|
|
|
|
|
component3Line = component3.lines[0 | y * component3.scaleY * scaleY];
|
|
|
|
|
component4Line = component4.lines[0 | y * component4.scaleY * scaleY];
|
|
|
|
|
for(x = 0; x < width; x++){
|
|
|
|
|
if (!colorTransform) {
|
|
|
|
|
C = component1Line[0 | x * component1.scaleX * scaleX];
|
|
|
|
|
M = component2Line[0 | x * component2.scaleX * scaleX];
|
|
|
|
|
Ye = component3Line[0 | x * component3.scaleX * scaleX];
|
|
|
|
|
K = component4Line[0 | x * component4.scaleX * scaleX];
|
|
|
|
|
} else {
|
|
|
|
|
Y = component1Line[0 | x * component1.scaleX * scaleX];
|
|
|
|
|
Cb = component2Line[0 | x * component2.scaleX * scaleX];
|
|
|
|
|
Cr = component3Line[0 | x * component3.scaleX * scaleX];
|
|
|
|
|
K = component4Line[0 | x * component4.scaleX * scaleX];
|
|
|
|
|
C = 255 - clampTo8bit(Y + 1.402 * (Cr - 128));
|
|
|
|
|
M = 255 - clampTo8bit(Y - 0.3441363 * (Cb - 128) - 0.71413636 * (Cr - 128));
|
|
|
|
|
Ye = 255 - clampTo8bit(Y + 1.772 * (Cb - 128));
|
|
|
|
|
}
|
|
|
|
|
data[offset++] = 255 - C;
|
|
|
|
|
data[offset++] = 255 - M;
|
|
|
|
|
data[offset++] = 255 - Ye;
|
|
|
|
|
data[offset++] = 255 - K;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
break;
|
|
|
|
|
default:
|
|
|
|
|
throw new Error("Unsupported color mode");
|
|
|
|
|
}
|
|
|
|
|
return data;
|
|
|
|
|
},
|
|
|
|
|
copyToImageData: function copyToImageData(imageData) {
|
|
|
|
|
const width = imageData.width, height = imageData.height;
|
|
|
|
|
const imageDataArray = imageData.data;
|
|
|
|
|
const data = this.getData(width, height);
|
|
|
|
|
let i = 0, j = 0, x, y;
|
|
|
|
|
let Y, K, C, M, R, G, B;
|
|
|
|
|
switch(this.components.length){
|
|
|
|
|
case 1:
|
|
|
|
|
for(y = 0; y < height; y++){
|
|
|
|
|
for(x = 0; x < width; x++){
|
|
|
|
|
Y = data[i++];
|
|
|
|
|
imageDataArray[j++] = Y;
|
|
|
|
|
imageDataArray[j++] = Y;
|
|
|
|
|
imageDataArray[j++] = Y;
|
|
|
|
|
imageDataArray[j++] = 255;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
break;
|
|
|
|
|
case 3:
|
|
|
|
|
for(y = 0; y < height; y++){
|
|
|
|
|
for(x = 0; x < width; x++){
|
|
|
|
|
R = data[i++];
|
|
|
|
|
G = data[i++];
|
|
|
|
|
B = data[i++];
|
|
|
|
|
imageDataArray[j++] = R;
|
|
|
|
|
imageDataArray[j++] = G;
|
|
|
|
|
imageDataArray[j++] = B;
|
|
|
|
|
imageDataArray[j++] = 255;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
break;
|
|
|
|
|
case 4:
|
|
|
|
|
for(y = 0; y < height; y++){
|
|
|
|
|
for(x = 0; x < width; x++){
|
|
|
|
|
C = data[i++];
|
|
|
|
|
M = data[i++];
|
|
|
|
|
Y = data[i++];
|
|
|
|
|
K = data[i++];
|
|
|
|
|
R = 255 - clampTo8bit(C * (1 - K / 255) + K);
|
|
|
|
|
G = 255 - clampTo8bit(M * (1 - K / 255) + K);
|
|
|
|
|
B = 255 - clampTo8bit(Y * (1 - K / 255) + K);
|
|
|
|
|
imageDataArray[j++] = R;
|
|
|
|
|
imageDataArray[j++] = G;
|
|
|
|
|
imageDataArray[j++] = B;
|
|
|
|
|
imageDataArray[j++] = 255;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
break;
|
|
|
|
|
default:
|
|
|
|
|
throw new Error("Unsupported color mode");
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
};
|
|
|
|
|
return constructor;
|
|
|
|
|
}();
|
2021-12-03 19:55:27 +03:00
|
|
|
const decode = function(jpegData, colorTransform = true) {
|
2021-01-22 12:39:57 +03:00
|
|
|
const arr = new Uint8Array(jpegData);
|
|
|
|
|
const decoder = new JpegImage();
|
|
|
|
|
decoder.parse(arr);
|
|
|
|
|
decoder.colorTransform = colorTransform;
|
2021-09-01 16:11:55 +03:00
|
|
|
const image = new Image();
|
2021-01-22 12:39:57 +03:00
|
|
|
image.height = decoder.height;
|
|
|
|
|
image.width = decoder.width;
|
|
|
|
|
image.data = new Uint8Array(decoder.width * decoder.height * 4);
|
|
|
|
|
decoder.copyToImageData(image);
|
|
|
|
|
return image;
|
|
|
|
|
};
|
2021-12-03 19:55:27 +03:00
|
|
|
export { decode as decode };
|
