/**
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* @licstart The following is the entire license notice for the
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* JavaScript code in this page
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*
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* Copyright 2022 Mozilla Foundation
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*
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* @licend The above is the entire license notice for the
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* JavaScript code in this page
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*/
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"use strict";
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Object.defineProperty(exports, "__esModule", {
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value: true
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});
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exports.JpegStream = void 0;
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var _decode_stream = require("./decode_stream.js");
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var _primitives = require("./primitives.js");
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var _jpg = require("./jpg.js");
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var _util = require("../shared/util.js");
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class JpegStream extends _decode_stream.DecodeStream {
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constructor(stream, maybeLength, params) {
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let ch;
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while ((ch = stream.getByte()) !== -1) {
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if (ch === 0xff) {
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stream.skip(-1);
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break;
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}
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}
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super(maybeLength);
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this.stream = stream;
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this.dict = stream.dict;
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this.maybeLength = maybeLength;
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this.params = params;
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}
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get bytes() {
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return (0, _util.shadow)(this, "bytes", this.stream.getBytes(this.maybeLength));
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}
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ensureBuffer(requested) {}
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readBlock() {
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if (this.eof) {
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return;
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}
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const jpegOptions = {
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decodeTransform: undefined,
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colorTransform: undefined
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};
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const decodeArr = this.dict.getArray("D", "Decode");
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if (this.forceRGB && Array.isArray(decodeArr)) {
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const bitsPerComponent = this.dict.get("BPC", "BitsPerComponent") || 8;
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const decodeArrLength = decodeArr.length;
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const transform = new Int32Array(decodeArrLength);
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let transformNeeded = false;
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const maxValue = (1 << bitsPerComponent) - 1;
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for (let i = 0; i < decodeArrLength; i += 2) {
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transform[i] = (decodeArr[i + 1] - decodeArr[i]) * 256 | 0;
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transform[i + 1] = decodeArr[i] * maxValue | 0;
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if (transform[i] !== 256 || transform[i + 1] !== 0) {
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transformNeeded = true;
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}
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}
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if (transformNeeded) {
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jpegOptions.decodeTransform = transform;
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}
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}
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if (this.params instanceof _primitives.Dict) {
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const colorTransform = this.params.get("ColorTransform");
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if (Number.isInteger(colorTransform)) {
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jpegOptions.colorTransform = colorTransform;
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}
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}
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const jpegImage = new _jpg.JpegImage(jpegOptions);
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jpegImage.parse(this.bytes);
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const data = jpegImage.getData({
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width: this.drawWidth,
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height: this.drawHeight,
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forceRGB: this.forceRGB,
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isSourcePDF: true
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});
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this.buffer = data;
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this.bufferLength = data.length;
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this.eof = true;
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}
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}
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exports.JpegStream = JpegStream;
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