lib/core/jpg.js

/**
 * @licstart The following is the entire license notice for the
 * Javascript code in this page
 *
 * Copyright 2020 Mozilla Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * @licend The above is the entire license notice for the
 * Javascript code in this page
 */
"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.JpegImage = void 0;

var _util = require("../shared/util.js");

var _core_utils = require("./core_utils.js");

class JpegError extends _util.BaseException {
  constructor(msg) {
    super(`JPEG error: ${msg}`);
  }

}

class DNLMarkerError extends _util.BaseException {
  constructor(message, scanLines) {
    super(message);
    this.scanLines = scanLines;
  }

}

class EOIMarkerError extends _util.BaseException {}

var JpegImage = function JpegImageClosure() {
  var dctZigZag = new Uint8Array([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]);
  var dctCos1 = 4017;
  var dctSin1 = 799;
  var dctCos3 = 3406;
  var dctSin3 = 2276;
  var dctCos6 = 1567;
  var dctSin6 = 3784;
  var dctSqrt2 = 5793;
  var dctSqrt1d2 = 2896;

  function JpegImage({
    decodeTransform = null,
    colorTransform = -1
  } = {}) {
    this._decodeTransform = decodeTransform;
    this._colorTransform = colorTransform;
  }

  function buildHuffmanTable(codeLengths, values) {
    var k = 0,
        code = [],
        i,
        j,
        length = 16;

    while (length > 0 && !codeLengths[length - 1]) {
      length--;
    }

    code.push({
      children: [],
      index: 0
    });
    var p = code[0],
        q;

    for (i = 0; i < length; i++) {
      for (j = 0; j < codeLengths[i]; j++) {
        p = code.pop();
        p.children[p.index] = values[k];

        while (p.index > 0) {
          p = code.pop();
        }

        p.index++;
        code.push(p);

        while (code.length <= i) {
          code.push(q = {
            children: [],
            index: 0
          });
          p.children[p.index] = q.children;
          p = q;
        }

        k++;
      }

      if (i + 1 < length) {
        code.push(q = {
          children: [],
          index: 0
        });
        p.children[p.index] = q.children;
        p = q;
      }
    }

    return code[0].children;
  }

  function getBlockBufferOffset(component, row, col) {
    return 64 * ((component.blocksPerLine + 1) * row + col);
  }

  function decodeScan(data, offset, frame, components, resetInterval, spectralStart, spectralEnd, successivePrev, successive, parseDNLMarker = false) {
    var mcusPerLine = frame.mcusPerLine;
    var progressive = frame.progressive;
    const startOffset = offset;
    let bitsData = 0,
        bitsCount = 0;

    function readBit() {
      if (bitsCount > 0) {
        bitsCount--;
        return bitsData >> bitsCount & 1;
      }

      bitsData = data[offset++];

      if (bitsData === 0xff) {
        var nextByte = data[offset++];

        if (nextByte) {
          if (nextByte === 0xdc && parseDNLMarker) {
            offset += 2;
            const scanLines = (0, _core_utils.readUint16)(data, offset);
            offset += 2;

            if (scanLines > 0 && scanLines !== frame.scanLines) {
              throw new DNLMarkerError("Found DNL marker (0xFFDC) while parsing scan data", scanLines);
            }
          } else if (nextByte === 0xd9) {
            if (parseDNLMarker) {
              const maybeScanLines = blockRow * (frame.precision === 8 ? 8 : 0);

              if (maybeScanLines > 0 && Math.round(frame.scanLines / maybeScanLines) >= 10) {
                throw new DNLMarkerError("Found EOI marker (0xFFD9) while parsing scan data, " + "possibly caused by incorrect `scanLines` parameter", maybeScanLines);
              }
            }

            throw new EOIMarkerError("Found EOI marker (0xFFD9) while parsing scan data");
          }

          throw new JpegError(`unexpected marker ${(bitsData << 8 | nextByte).toString(16)}`);
        }
      }

      bitsCount = 7;
      return bitsData >>> 7;
    }

    function decodeHuffman(tree) {
      var node = tree;

      while (true) {
        node = node[readBit()];

        switch (typeof node) {
          case "number":
            return node;

          case "object":
            continue;
        }

        throw new JpegError("invalid huffman sequence");
      }
    }

    function receive(length) {
      var n = 0;

      while (length > 0) {
        n = n << 1 | readBit();
        length--;
      }

      return n;
    }

    function receiveAndExtend(length) {
      if (length === 1) {
        return readBit() === 1 ? 1 : -1;
      }

      var n = receive(length);

      if (n >= 1 << length - 1) {
        return n;
      }

      return n + (-1 << length) + 1;
    }

    function decodeBaseline(component, blockOffset) {
      var t = decodeHuffman(component.huffmanTableDC);
      var diff = t === 0 ? 0 : receiveAndExtend(t);
      component.blockData[blockOffset] = component.pred += diff;
      var k = 1;

      while (k < 64) {
        var rs = decodeHuffman(component.huffmanTableAC);
        var s = rs & 15,
            r = rs >> 4;

        if (s === 0) {
          if (r < 15) {
            break;
          }

          k += 16;
          continue;
        }

        k += r;
        var z = dctZigZag[k];
        component.blockData[blockOffset + z] = receiveAndExtend(s);
        k++;
      }
    }

    function decodeDCFirst(component, blockOffset) {
      var t = decodeHuffman(component.huffmanTableDC);
      var diff = t === 0 ? 0 : receiveAndExtend(t) << successive;
      component.blockData[blockOffset] = component.pred += diff;
    }

    function decodeDCSuccessive(component, blockOffset) {
      component.blockData[blockOffset] |= readBit() << successive;
    }

    var eobrun = 0;

    function decodeACFirst(component, blockOffset) {
      if (eobrun > 0) {
        eobrun--;
        return;
      }

      var k = spectralStart,
          e = spectralEnd;

      while (k <= e) {
        var rs = decodeHuffman(component.huffmanTableAC);
        var s = rs & 15,
            r = rs >> 4;

        if (s === 0) {
          if (r < 15) {
            eobrun = receive(r) + (1 << r) - 1;
            break;
          }

          k += 16;
          continue;
        }

        k += r;
        var z = dctZigZag[k];
        component.blockData[blockOffset + z] = receiveAndExtend(s) * (1 << successive);
        k++;
      }
    }

    var successiveACState = 0,
        successiveACNextValue;

    function decodeACSuccessive(component, blockOffset) {
      var k = spectralStart;
      var e = spectralEnd;
      var r = 0;
      var s;
      var rs;

      while (k <= e) {
        const offsetZ = blockOffset + dctZigZag[k];
        const sign = component.blockData[offsetZ] < 0 ? -1 : 1;

        switch (successiveACState) {
          case 0:
            rs = decodeHuffman(component.huffmanTableAC);
            s = rs & 15;
            r = rs >> 4;

            if (s === 0) {
              if (r < 15) {
                eobrun = receive(r) + (1 << r);
                successiveACState = 4;
              } else {
                r = 16;
                successiveACState = 1;
              }
            } else {
              if (s !== 1) {
                throw new JpegError("invalid ACn encoding");
              }

              successiveACNextValue = receiveAndExtend(s);
              successiveACState = r ? 2 : 3;
            }

            continue;

          case 1:
          case 2:
            if (component.blockData[offsetZ]) {
              component.blockData[offsetZ] += sign * (readBit() << successive);
            } else {
              r--;

              if (r === 0) {
                successiveACState = successiveACState === 2 ? 3 : 0;
              }
            }

            break;

          case 3:
            if (component.blockData[offsetZ]) {
              component.blockData[offsetZ] += sign * (readBit() << successive);
            } else {
              component.blockData[offsetZ] = successiveACNextValue << successive;
              successiveACState = 0;
            }

            break;

          case 4:
            if (component.blockData[offsetZ]) {
              component.blockData[offsetZ] += sign * (readBit() << successive);
            }

            break;
        }

        k++;
      }

      if (successiveACState === 4) {
        eobrun--;

        if (eobrun === 0) {
          successiveACState = 0;
        }
      }
    }

    let blockRow = 0;

    function decodeMcu(component, decode, mcu, row, col) {
      var mcuRow = mcu / mcusPerLine | 0;
      var mcuCol = mcu % mcusPerLine;
      blockRow = mcuRow * component.v + row;
      var blockCol = mcuCol * component.h + col;
      const blockOffset = getBlockBufferOffset(component, blockRow, blockCol);
      decode(component, blockOffset);
    }

    function decodeBlock(component, decode, mcu) {
      blockRow = mcu / component.blocksPerLine | 0;
      var blockCol = mcu % component.blocksPerLine;
      const blockOffset = getBlockBufferOffset(component, blockRow, blockCol);
      decode(component, blockOffset);
    }

    var componentsLength = components.length;
    var component, i, j, k, n;
    var decodeFn;

    if (progressive) {
      if (spectralStart === 0) {
        decodeFn = successivePrev === 0 ? decodeDCFirst : decodeDCSuccessive;
      } else {
        decodeFn = successivePrev === 0 ? decodeACFirst : decodeACSuccessive;
      }
    } else {
      decodeFn = decodeBaseline;
    }

    var mcu = 0,
        fileMarker;
    var mcuExpected;

    if (componentsLength === 1) {
      mcuExpected = components[0].blocksPerLine * components[0].blocksPerColumn;
    } else {
      mcuExpected = mcusPerLine * frame.mcusPerColumn;
    }

    var h, v;

    while (mcu <= mcuExpected) {
      var mcuToRead = resetInterval ? Math.min(mcuExpected - mcu, resetInterval) : mcuExpected;

      if (mcuToRead > 0) {
        for (i = 0; i < componentsLength; i++) {
          components[i].pred = 0;
        }

        eobrun = 0;

        if (componentsLength === 1) {
          component = components[0];

          for (n = 0; n < mcuToRead; n++) {
            decodeBlock(component, decodeFn, mcu);
            mcu++;
          }
        } else {
          for (n = 0; n < mcuToRead; n++) {
            for (i = 0; i < componentsLength; i++) {
              component = components[i];
              h = component.h;
              v = component.v;

              for (j = 0; j < v; j++) {
                for (k = 0; k < h; k++) {
                  decodeMcu(component, decodeFn, mcu, j, k);
                }
              }
            }

            mcu++;
          }
        }
      }

      bitsCount = 0;
      fileMarker = findNextFileMarker(data, offset);

      if (!fileMarker) {
        break;
      }

      if (fileMarker.invalid) {
        const partialMsg = mcuToRead > 0 ? "unexpected" : "excessive";
        (0, _util.warn)(`decodeScan - ${partialMsg} MCU data, current marker is: ${fileMarker.invalid}`);
        offset = fileMarker.offset;
      }

      if (fileMarker.marker >= 0xffd0 && fileMarker.marker <= 0xffd7) {
        offset += 2;
      } else {
        break;
      }
    }

    return offset - startOffset;
  }

  function quantizeAndInverse(component, blockBufferOffset, p) {
    var qt = component.quantizationTable,
        blockData = component.blockData;
    var v0, v1, v2, v3, v4, v5, v6, v7;
    var p0, p1, p2, p3, p4, p5, p6, p7;
    var t;

    if (!qt) {
      throw new JpegError("missing required Quantization Table.");
    }

    for (var row = 0; row < 64; row += 8) {
      p0 = blockData[blockBufferOffset + row];
      p1 = blockData[blockBufferOffset + row + 1];
      p2 = blockData[blockBufferOffset + row + 2];
      p3 = blockData[blockBufferOffset + row + 3];
      p4 = blockData[blockBufferOffset + row + 4];
      p5 = blockData[blockBufferOffset + row + 5];
      p6 = blockData[blockBufferOffset + row + 6];
      p7 = blockData[blockBufferOffset + row + 7];
      p0 *= qt[row];

      if ((p1 | p2 | p3 | p4 | p5 | p6 | p7) === 0) {
        t = dctSqrt2 * p0 + 512 >> 10;
        p[row] = t;
        p[row + 1] = t;
        p[row + 2] = t;
        p[row + 3] = t;
        p[row + 4] = t;
        p[row + 5] = t;
        p[row + 6] = t;
        p[row + 7] = t;
        continue;
      }

      p1 *= qt[row + 1];
      p2 *= qt[row + 2];
      p3 *= qt[row + 3];
      p4 *= qt[row + 4];
      p5 *= qt[row + 5];
      p6 *= qt[row + 6];
      p7 *= qt[row + 7];
      v0 = dctSqrt2 * p0 + 128 >> 8;
      v1 = dctSqrt2 * p4 + 128 >> 8;
      v2 = p2;
      v3 = p6;
      v4 = dctSqrt1d2 * (p1 - p7) + 128 >> 8;
      v7 = dctSqrt1d2 * (p1 + p7) + 128 >> 8;
      v5 = p3 << 4;
      v6 = p5 << 4;
      v0 = v0 + v1 + 1 >> 1;
      v1 = v0 - v1;
      t = v2 * dctSin6 + v3 * dctCos6 + 128 >> 8;
      v2 = v2 * dctCos6 - v3 * dctSin6 + 128 >> 8;
      v3 = t;
      v4 = v4 + v6 + 1 >> 1;
      v6 = v4 - v6;
      v7 = v7 + v5 + 1 >> 1;
      v5 = v7 - v5;
      v0 = v0 + v3 + 1 >> 1;
      v3 = v0 - v3;
      v1 = v1 + v2 + 1 >> 1;
      v2 = v1 - v2;
      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[row] = v0 + v7;
      p[row + 7] = v0 - v7;
      p[row + 1] = v1 + v6;
      p[row + 6] = v1 - v6;
      p[row + 2] = v2 + v5;
      p[row + 5] = v2 - v5;
      p[row + 3] = v3 + v4;
      p[row + 4] = v3 - v4;
    }

    for (var col = 0; col < 8; ++col) {
      p0 = p[col];
      p1 = p[col + 8];
      p2 = p[col + 16];
      p3 = p[col + 24];
      p4 = p[col + 32];
      p5 = p[col + 40];
      p6 = p[col + 48];
      p7 = p[col + 56];

      if ((p1 | p2 | p3 | p4 | p5 | p6 | p7) === 0) {
        t = dctSqrt2 * p0 + 8192 >> 14;

        if (t < -2040) {
          t = 0;
        } else if (t >= 2024) {
          t = 255;
        } else {
          t = t + 2056 >> 4;
        }

        blockData[blockBufferOffset + col] = t;
        blockData[blockBufferOffset + col + 8] = t;
        blockData[blockBufferOffset + col + 16] = t;
        blockData[blockBufferOffset + col + 24] = t;
        blockData[blockBufferOffset + col + 32] = t;
        blockData[blockBufferOffset + col + 40] = t;
        blockData[blockBufferOffset + col + 48] = t;
        blockData[blockBufferOffset + col + 56] = t;
        continue;
      }

      v0 = dctSqrt2 * p0 + 2048 >> 12;
      v1 = dctSqrt2 * p4 + 2048 >> 12;
      v2 = p2;
      v3 = p6;
      v4 = dctSqrt1d2 * (p1 - p7) + 2048 >> 12;
      v7 = dctSqrt1d2 * (p1 + p7) + 2048 >> 12;
      v5 = p3;
      v6 = p5;
      v0 = (v0 + v1 + 1 >> 1) + 4112;
      v1 = v0 - v1;
      t = v2 * dctSin6 + v3 * dctCos6 + 2048 >> 12;
      v2 = v2 * dctCos6 - v3 * dctSin6 + 2048 >> 12;
      v3 = t;
      v4 = v4 + v6 + 1 >> 1;
      v6 = v4 - v6;
      v7 = v7 + v5 + 1 >> 1;
      v5 = v7 - v5;
      v0 = v0 + v3 + 1 >> 1;
      v3 = v0 - v3;
      v1 = v1 + v2 + 1 >> 1;
      v2 = v1 - v2;
      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;
      p0 = v0 + v7;
      p7 = v0 - v7;
      p1 = v1 + v6;
      p6 = v1 - v6;
      p2 = v2 + v5;
      p5 = v2 - v5;
      p3 = v3 + v4;
      p4 = v3 - v4;

      if (p0 < 16) {
        p0 = 0;
      } else if (p0 >= 4080) {
        p0 = 255;
      } else {
        p0 >>= 4;
      }

      if (p1 < 16) {
        p1 = 0;
      } else if (p1 >= 4080) {
        p1 = 255;
      } else {
        p1 >>= 4;
      }

      if (p2 < 16) {
        p2 = 0;
      } else if (p2 >= 4080) {
        p2 = 255;
      } else {
        p2 >>= 4;
      }

      if (p3 < 16) {
        p3 = 0;
      } else if (p3 >= 4080) {
        p3 = 255;
      } else {
        p3 >>= 4;
      }

      if (p4 < 16) {
        p4 = 0;
      } else if (p4 >= 4080) {
        p4 = 255;
      } else {
        p4 >>= 4;
      }

      if (p5 < 16) {
        p5 = 0;
      } else if (p5 >= 4080) {
        p5 = 255;
      } else {
        p5 >>= 4;
      }

      if (p6 < 16) {
        p6 = 0;
      } else if (p6 >= 4080) {
        p6 = 255;
      } else {
        p6 >>= 4;
      }

      if (p7 < 16) {
        p7 = 0;
      } else if (p7 >= 4080) {
        p7 = 255;
      } else {
        p7 >>= 4;
      }

      blockData[blockBufferOffset + col] = p0;
      blockData[blockBufferOffset + col + 8] = p1;
      blockData[blockBufferOffset + col + 16] = p2;
      blockData[blockBufferOffset + col + 24] = p3;
      blockData[blockBufferOffset + col + 32] = p4;
      blockData[blockBufferOffset + col + 40] = p5;
      blockData[blockBufferOffset + col + 48] = p6;
      blockData[blockBufferOffset + col + 56] = p7;
    }
  }

  function buildComponentData(frame, component) {
    var blocksPerLine = component.blocksPerLine;
    var blocksPerColumn = component.blocksPerColumn;
    var computationBuffer = new Int16Array(64);

    for (var blockRow = 0; blockRow < blocksPerColumn; blockRow++) {
      for (var blockCol = 0; blockCol < blocksPerLine; blockCol++) {
        var offset = getBlockBufferOffset(component, blockRow, blockCol);
        quantizeAndInverse(component, offset, computationBuffer);
      }
    }

    return component.blockData;
  }

  function findNextFileMarker(data, currentPos, startPos = currentPos) {
    const maxPos = data.length - 1;
    var newPos = startPos < currentPos ? startPos : currentPos;

    if (currentPos >= maxPos) {
      return null;
    }

    var currentMarker = (0, _core_utils.readUint16)(data, currentPos);

    if (currentMarker >= 0xffc0 && currentMarker <= 0xfffe) {
      return {
        invalid: null,
        marker: currentMarker,
        offset: currentPos
      };
    }

    var newMarker = (0, _core_utils.readUint16)(data, newPos);

    while (!(newMarker >= 0xffc0 && newMarker <= 0xfffe)) {
      if (++newPos >= maxPos) {
        return null;
      }

      newMarker = (0, _core_utils.readUint16)(data, newPos);
    }

    return {
      invalid: currentMarker.toString(16),
      marker: newMarker,
      offset: newPos
    };
  }

  JpegImage.prototype = {
    parse(data, {
      dnlScanLines = null
    } = {}) {
      function readDataBlock() {
        const length = (0, _core_utils.readUint16)(data, offset);
        offset += 2;
        let endOffset = offset + length - 2;
        var fileMarker = findNextFileMarker(data, endOffset, offset);

        if (fileMarker && fileMarker.invalid) {
          (0, _util.warn)("readDataBlock - incorrect length, current marker is: " + fileMarker.invalid);
          endOffset = fileMarker.offset;
        }

        var array = data.subarray(offset, endOffset);
        offset += array.length;
        return array;
      }

      function prepareComponents(frame) {
        var mcusPerLine = Math.ceil(frame.samplesPerLine / 8 / frame.maxH);
        var mcusPerColumn = Math.ceil(frame.scanLines / 8 / frame.maxV);

        for (var i = 0; i < frame.components.length; i++) {
          component = frame.components[i];
          var blocksPerLine = Math.ceil(Math.ceil(frame.samplesPerLine / 8) * component.h / frame.maxH);
          var blocksPerColumn = Math.ceil(Math.ceil(frame.scanLines / 8) * component.v / frame.maxV);
          var blocksPerLineForMcu = mcusPerLine * component.h;
          var blocksPerColumnForMcu = mcusPerColumn * component.v;
          var blocksBufferSize = 64 * blocksPerColumnForMcu * (blocksPerLineForMcu + 1);
          component.blockData = new Int16Array(blocksBufferSize);
          component.blocksPerLine = blocksPerLine;
          component.blocksPerColumn = blocksPerColumn;
        }

        frame.mcusPerLine = mcusPerLine;
        frame.mcusPerColumn = mcusPerColumn;
      }

      var offset = 0;
      var jfif = null;
      var adobe = null;
      var frame, resetInterval;
      let numSOSMarkers = 0;
      var quantizationTables = [];
      var huffmanTablesAC = [],
          huffmanTablesDC = [];
      let fileMarker = (0, _core_utils.readUint16)(data, offset);
      offset += 2;

      if (fileMarker !== 0xffd8) {
        throw new JpegError("SOI not found");
      }

      fileMarker = (0, _core_utils.readUint16)(data, offset);
      offset += 2;

      markerLoop: while (fileMarker !== 0xffd9) {
        var i, j, l;

        switch (fileMarker) {
          case 0xffe0:
          case 0xffe1:
          case 0xffe2:
          case 0xffe3:
          case 0xffe4:
          case 0xffe5:
          case 0xffe6:
          case 0xffe7:
          case 0xffe8:
          case 0xffe9:
          case 0xffea:
          case 0xffeb:
          case 0xffec:
          case 0xffed:
          case 0xffee:
          case 0xffef:
          case 0xfffe:
            var appData = readDataBlock();

            if (fileMarker === 0xffe0) {
              if (appData[0] === 0x4a && appData[1] === 0x46 && appData[2] === 0x49 && appData[3] === 0x46 && 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 === 0xffee) {
              if (appData[0] === 0x41 && appData[1] === 0x64 && appData[2] === 0x6f && appData[3] === 0x62 && appData[4] === 0x65) {
                adobe = {
                  version: appData[5] << 8 | appData[6],
                  flags0: appData[7] << 8 | appData[8],
                  flags1: appData[9] << 8 | appData[10],
                  transformCode: appData[11]
                };
              }
            }

            break;

          case 0xffdb:
            const quantizationTablesLength = (0, _core_utils.readUint16)(data, offset);
            offset += 2;
            var quantizationTablesEnd = quantizationTablesLength + offset - 2;
            var z;

            while (offset < quantizationTablesEnd) {
              var quantizationTableSpec = data[offset++];
              var tableData = new Uint16Array(64);

              if (quantizationTableSpec >> 4 === 0) {
                for (j = 0; j < 64; j++) {
                  z = dctZigZag[j];
                  tableData[z] = data[offset++];
                }
              } else if (quantizationTableSpec >> 4 === 1) {
                for (j = 0; j < 64; j++) {
                  z = dctZigZag[j];
                  tableData[z] = (0, _core_utils.readUint16)(data, offset);
                  offset += 2;
                }
              } else {
                throw new JpegError("DQT - invalid table spec");
              }

              quantizationTables[quantizationTableSpec & 15] = tableData;
            }

            break;

          case 0xffc0:
          case 0xffc1:
          case 0xffc2:
            if (frame) {
              throw new JpegError("Only single frame JPEGs supported");
            }

            offset += 2;
            frame = {};
            frame.extended = fileMarker === 0xffc1;
            frame.progressive = fileMarker === 0xffc2;
            frame.precision = data[offset++];
            const sofScanLines = (0, _core_utils.readUint16)(data, offset);
            offset += 2;
            frame.scanLines = dnlScanLines || sofScanLines;
            frame.samplesPerLine = (0, _core_utils.readUint16)(data, offset);
            offset += 2;
            frame.components = [];
            frame.componentIds = {};
            var componentsCount = data[offset++],
                componentId;
            var maxH = 0,
                maxV = 0;

            for (i = 0; i < componentsCount; i++) {
              componentId = data[offset];
              var h = data[offset + 1] >> 4;
              var v = data[offset + 1] & 15;

              if (maxH < h) {
                maxH = h;
              }

              if (maxV < v) {
                maxV = v;
              }

              var qId = data[offset + 2];
              l = frame.components.push({
                h,
                v,
                quantizationId: qId,
                quantizationTable: null
              });
              frame.componentIds[componentId] = l - 1;
              offset += 3;
            }

            frame.maxH = maxH;
            frame.maxV = maxV;
            prepareComponents(frame);
            break;

          case 0xffc4:
            const huffmanLength = (0, _core_utils.readUint16)(data, offset);
            offset += 2;

            for (i = 2; i < huffmanLength;) {
              var huffmanTableSpec = data[offset++];
              var codeLengths = new Uint8Array(16);
              var codeLengthSum = 0;

              for (j = 0; j < 16; j++, offset++) {
                codeLengthSum += codeLengths[j] = data[offset];
              }

              var 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 0xffdd:
            offset += 2;
            resetInterval = (0, _core_utils.readUint16)(data, offset);
            offset += 2;
            break;

          case 0xffda:
            const parseDNLMarker = ++numSOSMarkers === 1 && !dnlScanLines;
            offset += 2;
            var selectorsCount = data[offset++];
            var components = [],
                component;

            for (i = 0; i < selectorsCount; i++) {
              const index = data[offset++];
              var componentIndex = frame.componentIds[index];
              component = frame.components[componentIndex];
              component.index = index;
              var tableSpec = data[offset++];
              component.huffmanTableDC = huffmanTablesDC[tableSpec >> 4];
              component.huffmanTableAC = huffmanTablesAC[tableSpec & 15];
              components.push(component);
            }

            var spectralStart = data[offset++];
            var spectralEnd = data[offset++];
            var successiveApproximation = data[offset++];

            try {
              var processed = decodeScan(data, offset, frame, components, resetInterval, spectralStart, spectralEnd, successiveApproximation >> 4, successiveApproximation & 15, parseDNLMarker);
              offset += processed;
            } catch (ex) {
              if (ex instanceof DNLMarkerError) {
                (0, _util.warn)(`${ex.message} -- attempting to re-parse the JPEG image.`);
                return this.parse(data, {
                  dnlScanLines: ex.scanLines
                });
              } else if (ex instanceof EOIMarkerError) {
                (0, _util.warn)(`${ex.message} -- ignoring the rest of the image data.`);
                break markerLoop;
              }

              throw ex;
            }

            break;

          case 0xffdc:
            offset += 4;
            break;

          case 0xffff:
            if (data[offset] !== 0xff) {
              offset--;
            }

            break;

          default:
            const nextFileMarker = findNextFileMarker(data, offset - 2, offset - 3);

            if (nextFileMarker && nextFileMarker.invalid) {
              (0, _util.warn)("JpegImage.parse - unexpected data, current marker is: " + nextFileMarker.invalid);
              offset = nextFileMarker.offset;
              break;
            }

            if (offset >= data.length - 1) {
              (0, _util.warn)("JpegImage.parse - reached the end of the image data " + "without finding an EOI marker (0xFFD9).");
              break markerLoop;
            }

            throw new JpegError("JpegImage.parse - unknown marker: " + fileMarker.toString(16));
        }

        fileMarker = (0, _core_utils.readUint16)(data, offset);
        offset += 2;
      }

      this.width = frame.samplesPerLine;
      this.height = frame.scanLines;
      this.jfif = jfif;
      this.adobe = adobe;
      this.components = [];

      for (i = 0; i < frame.components.length; i++) {
        component = frame.components[i];
        var quantizationTable = quantizationTables[component.quantizationId];

        if (quantizationTable) {
          component.quantizationTable = quantizationTable;
        }

        this.components.push({
          index: component.index,
          output: buildComponentData(frame, component),
          scaleX: component.h / frame.maxH,
          scaleY: component.v / frame.maxV,
          blocksPerLine: component.blocksPerLine,
          blocksPerColumn: component.blocksPerColumn
        });
      }

      this.numComponents = this.components.length;
      return undefined;
    },

    _getLinearizedBlockData(width, height, isSourcePDF = false) {
      var scaleX = this.width / width,
          scaleY = this.height / height;
      var component, componentScaleX, componentScaleY, blocksPerScanline;
      var x, y, i, j, k;
      var index;
      var offset = 0;
      var output;
      var numComponents = this.components.length;
      var dataLength = width * height * numComponents;
      var data = new Uint8ClampedArray(dataLength);
      var xScaleBlockOffset = new Uint32Array(width);
      var mask3LSB = 0xfffffff8;
      let lastComponentScaleX;

      for (i = 0; i < numComponents; i++) {
        component = this.components[i];
        componentScaleX = component.scaleX * scaleX;
        componentScaleY = component.scaleY * scaleY;
        offset = i;
        output = component.output;
        blocksPerScanline = component.blocksPerLine + 1 << 3;

        if (componentScaleX !== lastComponentScaleX) {
          for (x = 0; x < width; x++) {
            j = 0 | x * componentScaleX;
            xScaleBlockOffset[x] = (j & mask3LSB) << 3 | j & 7;
          }

          lastComponentScaleX = componentScaleX;
        }

        for (y = 0; y < height; y++) {
          j = 0 | y * componentScaleY;
          index = blocksPerScanline * (j & mask3LSB) | (j & 7) << 3;

          for (x = 0; x < width; x++) {
            data[offset] = output[index + xScaleBlockOffset[x]];
            offset += numComponents;
          }
        }
      }

      let transform = this._decodeTransform;

      if (!isSourcePDF && numComponents === 4 && !transform) {
        transform = new Int32Array([-256, 255, -256, 255, -256, 255, -256, 255]);
      }

      if (transform) {
        for (i = 0; i < dataLength;) {
          for (j = 0, k = 0; j < numComponents; j++, i++, k += 2) {
            data[i] = (data[i] * transform[k] >> 8) + transform[k + 1];
          }
        }
      }

      return data;
    },

    get _isColorConversionNeeded() {
      if (this.adobe) {
        return !!this.adobe.transformCode;
      }

      if (this.numComponents === 3) {
        if (this._colorTransform === 0) {
          return false;
        } else if (this.components[0].index === 0x52 && this.components[1].index === 0x47 && this.components[2].index === 0x42) {
          return false;
        }

        return true;
      }

      if (this._colorTransform === 1) {
        return true;
      }

      return false;
    },

    _convertYccToRgb: function convertYccToRgb(data) {
      var Y, Cb, Cr;

      for (var i = 0, length = data.length; i < length; i += 3) {
        Y = data[i];
        Cb = data[i + 1];
        Cr = data[i + 2];
        data[i] = Y - 179.456 + 1.402 * Cr;
        data[i + 1] = Y + 135.459 - 0.344 * Cb - 0.714 * Cr;
        data[i + 2] = Y - 226.816 + 1.772 * Cb;
      }

      return data;
    },
    _convertYcckToRgb: function convertYcckToRgb(data) {
      var Y, Cb, Cr, k;
      var offset = 0;

      for (var i = 0, length = data.length; i < length; i += 4) {
        Y = data[i];
        Cb = data[i + 1];
        Cr = data[i + 2];
        k = data[i + 3];
        data[offset++] = -122.67195406894 + Cb * (-6.60635669420364e-5 * Cb + 0.000437130475926232 * Cr - 5.4080610064599e-5 * Y + 0.00048449797120281 * k - 0.154362151871126) + Cr * (-0.000957964378445773 * Cr + 0.000817076911346625 * Y - 0.00477271405408747 * k + 1.53380253221734) + Y * (0.000961250184130688 * Y - 0.00266257332283933 * k + 0.48357088451265) + k * (-0.000336197177618394 * k + 0.484791561490776);
        data[offset++] = 107.268039397724 + Cb * (2.19927104525741e-5 * Cb - 0.000640992018297945 * Cr + 0.000659397001245577 * Y + 0.000426105652938837 * k - 0.176491792462875) + Cr * (-0.000778269941513683 * Cr + 0.00130872261408275 * Y + 0.000770482631801132 * k - 0.151051492775562) + Y * (0.00126935368114843 * Y - 0.00265090189010898 * k + 0.25802910206845) + k * (-0.000318913117588328 * k - 0.213742400323665);
        data[offset++] = -20.810012546947 + Cb * (-0.000570115196973677 * Cb - 2.63409051004589e-5 * Cr + 0.0020741088115012 * Y - 0.00288260236853442 * k + 0.814272968359295) + Cr * (-1.53496057440975e-5 * Cr - 0.000132689043961446 * Y + 0.000560833691242812 * k - 0.195152027534049) + Y * (0.00174418132927582 * Y - 0.00255243321439347 * k + 0.116935020465145) + k * (-0.000343531996510555 * k + 0.24165260232407);
      }

      return data.subarray(0, offset);
    },
    _convertYcckToCmyk: function convertYcckToCmyk(data) {
      var Y, Cb, Cr;

      for (var i = 0, length = data.length; i < length; i += 4) {
        Y = data[i];
        Cb = data[i + 1];
        Cr = data[i + 2];
        data[i] = 434.456 - Y - 1.402 * Cr;
        data[i + 1] = 119.541 - Y + 0.344 * Cb + 0.714 * Cr;
        data[i + 2] = 481.816 - Y - 1.772 * Cb;
      }

      return data;
    },
    _convertCmykToRgb: function convertCmykToRgb(data) {
      var c, m, y, k;
      var offset = 0;

      for (var i = 0, length = data.length; i < length; i += 4) {
        c = data[i];
        m = data[i + 1];
        y = data[i + 2];
        k = data[i + 3];
        data[offset++] = 255 + c * (-0.00006747147073602441 * c + 0.0008379262121013727 * m + 0.0002894718188643294 * y + 0.003264231057537806 * k - 1.1185611867203937) + m * (0.000026374107616089405 * m - 0.00008626949158638572 * y - 0.0002748769067499491 * k - 0.02155688794978967) + y * (-0.00003878099212869363 * y - 0.0003267808279485286 * k + 0.0686742238595345) - k * (0.0003361971776183937 * k + 0.7430659151342254);
        data[offset++] = 255 + c * (0.00013596372813588848 * c + 0.000924537132573585 * m + 0.00010567359618683593 * y + 0.0004791864687436512 * k - 0.3109689587515875) + m * (-0.00023545346108370344 * m + 0.0002702845253534714 * y + 0.0020200308977307156 * k - 0.7488052167015494) + y * (0.00006834815998235662 * y + 0.00015168452363460973 * k - 0.09751927774728933) - k * (0.00031891311758832814 * k + 0.7364883807733168);
        data[offset++] = 255 + c * (0.000013598650411385307 * c + 0.00012423956175490851 * m + 0.0004751985097583589 * y - 0.0000036729317476630422 * k - 0.05562186980264034) + m * (0.00016141380598724676 * m + 0.0009692239130725186 * y + 0.0007782692450036253 * k - 0.44015232367526463) + y * (5.068882914068769e-7 * y + 0.0017778369011375071 * k - 0.7591454649749609) - k * (0.0003435319965105553 * k + 0.7063770186160144);
      }

      return data.subarray(0, offset);
    },

    getData({
      width,
      height,
      forceRGB = false,
      isSourcePDF = false
    }) {
      if (this.numComponents > 4) {
        throw new JpegError("Unsupported color mode");
      }

      var data = this._getLinearizedBlockData(width, height, isSourcePDF);

      if (this.numComponents === 1 && forceRGB) {
        var dataLength = data.length;
        var rgbData = new Uint8ClampedArray(dataLength * 3);
        var offset = 0;

        for (var i = 0; i < dataLength; i++) {
          var grayColor = data[i];
          rgbData[offset++] = grayColor;
          rgbData[offset++] = grayColor;
          rgbData[offset++] = grayColor;
        }

        return rgbData;
      } else if (this.numComponents === 3 && this._isColorConversionNeeded) {
        return this._convertYccToRgb(data);
      } else if (this.numComponents === 4) {
        if (this._isColorConversionNeeded) {
          if (forceRGB) {
            return this._convertYcckToRgb(data);
          }

          return this._convertYcckToCmyk(data);
        } else if (forceRGB) {
          return this._convertCmykToRgb(data);
        }
      }

      return data;
    }

  };
  return JpegImage;
}();

exports.JpegImage = JpegImage;