pdfjs-dist/lib/core/ccitt.js

/**
 * @licstart The following is the entire license notice for the
 * Javascript code in this page
 *
 * Copyright 2022 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.CCITTFaxDecoder = void 0;

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

const ccittEOL = -2;
const ccittEOF = -1;
const twoDimPass = 0;
const twoDimHoriz = 1;
const twoDimVert0 = 2;
const twoDimVertR1 = 3;
const twoDimVertL1 = 4;
const twoDimVertR2 = 5;
const twoDimVertL2 = 6;
const twoDimVertR3 = 7;
const twoDimVertL3 = 8;
const twoDimTable = [[-1, -1], [-1, -1], [7, twoDimVertL3], [7, twoDimVertR3], [6, twoDimVertL2], [6, twoDimVertL2], [6, twoDimVertR2], [6, twoDimVertR2], [4, twoDimPass], [4, twoDimPass], [4, twoDimPass], [4, twoDimPass], [4, twoDimPass], [4, twoDimPass], [4, twoDimPass], [4, twoDimPass], [3, twoDimHoriz], [3, twoDimHoriz], [3, twoDimHoriz], [3, twoDimHoriz], [3, twoDimHoriz], [3, twoDimHoriz], [3, twoDimHoriz], [3, twoDimHoriz], [3, twoDimHoriz], [3, twoDimHoriz], [3, twoDimHoriz], [3, twoDimHoriz], [3, twoDimHoriz], [3, twoDimHoriz], [3, twoDimHoriz], [3, twoDimHoriz], [3, twoDimVertL1], [3, twoDimVertL1], [3, twoDimVertL1], [3, twoDimVertL1], [3, twoDimVertL1], [3, twoDimVertL1], [3, twoDimVertL1], [3, twoDimVertL1], [3, twoDimVertL1], [3, twoDimVertL1], [3, twoDimVertL1], [3, twoDimVertL1], [3, twoDimVertL1], [3, twoDimVertL1], [3, twoDimVertL1], [3, twoDimVertL1], [3, twoDimVertR1], [3, twoDimVertR1], [3, twoDimVertR1], [3, twoDimVertR1], [3, twoDimVertR1], [3, twoDimVertR1], [3, twoDimVertR1], [3, twoDimVertR1], [3, twoDimVertR1], [3, twoDimVertR1], [3, twoDimVertR1], [3, twoDimVertR1], [3, twoDimVertR1], [3, twoDimVertR1], [3, twoDimVertR1], [3, twoDimVertR1], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0], [1, twoDimVert0]];
const whiteTable1 = [[-1, -1], [12, ccittEOL], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [11, 1792], [11, 1792], [12, 1984], [12, 2048], [12, 2112], [12, 2176], [12, 2240], [12, 2304], [11, 1856], [11, 1856], [11, 1920], [11, 1920], [12, 2368], [12, 2432], [12, 2496], [12, 2560]];
const whiteTable2 = [[-1, -1], [-1, -1], [-1, -1], [-1, -1], [8, 29], [8, 29], [8, 30], [8, 30], [8, 45], [8, 45], [8, 46], [8, 46], [7, 22], [7, 22], [7, 22], [7, 22], [7, 23], [7, 23], [7, 23], [7, 23], [8, 47], [8, 47], [8, 48], [8, 48], [6, 13], [6, 13], [6, 13], [6, 13], [6, 13], [6, 13], [6, 13], [6, 13], [7, 20], [7, 20], [7, 20], [7, 20], [8, 33], [8, 33], [8, 34], [8, 34], [8, 35], [8, 35], [8, 36], [8, 36], [8, 37], [8, 37], [8, 38], [8, 38], [7, 19], [7, 19], [7, 19], [7, 19], [8, 31], [8, 31], [8, 32], [8, 32], [6, 1], [6, 1], [6, 1], [6, 1], [6, 1], [6, 1], [6, 1], [6, 1], [6, 12], [6, 12], [6, 12], [6, 12], [6, 12], [6, 12], [6, 12], [6, 12], [8, 53], [8, 53], [8, 54], [8, 54], [7, 26], [7, 26], [7, 26], [7, 26], [8, 39], [8, 39], [8, 40], [8, 40], [8, 41], [8, 41], [8, 42], [8, 42], [8, 43], [8, 43], [8, 44], [8, 44], [7, 21], [7, 21], [7, 21], [7, 21], [7, 28], [7, 28], [7, 28], [7, 28], [8, 61], [8, 61], [8, 62], [8, 62], [8, 63], [8, 63], [8, 0], [8, 0], [8, 320], [8, 320], [8, 384], [8, 384], [5, 10], [5, 10], [5, 10], [5, 10], [5, 10], [5, 10], [5, 10], [5, 10], [5, 10], [5, 10], [5, 10], [5, 10], [5, 10], [5, 10], [5, 10], [5, 10], [5, 11], [5, 11], [5, 11], [5, 11], [5, 11], [5, 11], [5, 11], [5, 11], [5, 11], [5, 11], [5, 11], [5, 11], [5, 11], [5, 11], [5, 11], [5, 11], [7, 27], [7, 27], [7, 27], [7, 27], [8, 59], [8, 59], [8, 60], [8, 60], [9, 1472], [9, 1536], [9, 1600], [9, 1728], [7, 18], [7, 18], [7, 18], [7, 18], [7, 24], [7, 24], [7, 24], [7, 24], [8, 49], [8, 49], [8, 50], [8, 50], [8, 51], [8, 51], [8, 52], [8, 52], [7, 25], [7, 25], [7, 25], [7, 25], [8, 55], [8, 55], [8, 56], [8, 56], [8, 57], [8, 57], [8, 58], [8, 58], [6, 192], [6, 192], [6, 192], [6, 192], [6, 192], [6, 192], [6, 192], [6, 192], [6, 1664], [6, 1664], [6, 1664], [6, 1664], [6, 1664], [6, 1664], [6, 1664], [6, 1664], [8, 448], [8, 448], [8, 512], [8, 512], [9, 704], [9, 768], [8, 640], [8, 640], [8, 576], [8, 576], [9, 832], [9, 896], [9, 960], [9, 1024], [9, 1088], [9, 1152], [9, 1216], [9, 1280], [9, 1344], [9, 1408], [7, 256], [7, 256], [7, 256], [7, 256], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 2], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [4, 3], [5, 128], [5, 128], [5, 128], [5, 128], [5, 128], [5, 128], [5, 128], [5, 128], [5, 128], [5, 128], [5, 128], [5, 128], [5, 128], [5, 128], [5, 128], [5, 128], [5, 8], [5, 8], [5, 8], [5, 8], [5, 8], [5, 8], [5, 8], [5, 8], [5, 8], [5, 8], [5, 8], [5, 8], [5, 8], [5, 8], [5, 8], [5, 8], [5, 9], [5, 9], [5, 9], [5, 9], [5, 9], [5, 9], [5, 9], [5, 9], [5, 9], [5, 9], [5, 9], [5, 9], [5, 9], [5, 9], [5, 9], [5, 9], [6, 16], [6, 16], [6, 16], [6, 16], [6, 16], [6, 16], [6, 16], [6, 16], [6, 17], [6, 17], [6, 17], [6, 17], [6, 17], [6, 17], [6, 17], [6, 17], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 4], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [4, 5], [6, 14], [6, 14], [6, 14], [6, 14], [6, 14], [6, 14], [6, 14], [6, 14], [6, 15], [6, 15], [6, 15], [6, 15], [6, 15], [6, 15], [6, 15], [6, 15], [5, 64], [5, 64], [5, 64], [5, 64], [5, 64], [5, 64], [5, 64], [5, 64], [5, 64], [5, 64], [5, 64], [5, 64], [5, 64], [5, 64], [5, 64], [5, 64], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 6], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7], [4, 7]];
const blackTable1 = [[-1, -1], [-1, -1], [12, ccittEOL], [12, ccittEOL], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [-1, -1], [11, 1792], [11, 1792], [11, 1792], [11, 1792], [12, 1984], [12, 1984], [12, 2048], [12, 2048], [12, 2112], [12, 2112], [12, 2176], [12, 2176], [12, 2240], [12, 2240], [12, 2304], [12, 2304], [11, 1856], [11, 1856], [11, 1856], [11, 1856], [11, 1920], [11, 1920], [11, 1920], [11, 1920], [12, 2368], [12, 2368], [12, 2432], [12, 2432], [12, 2496], [12, 2496], [12, 2560], [12, 2560], [10, 18], [10, 18], [10, 18], [10, 18], [10, 18], [10, 18], [10, 18], [10, 18], [12, 52], [12, 52], [13, 640], [13, 704], [13, 768], [13, 832], [12, 55], [12, 55], [12, 56], [12, 56], [13, 1280], [13, 1344], [13, 1408], [13, 1472], [12, 59], [12, 59], [12, 60], [12, 60], [13, 1536], [13, 1600], [11, 24], [11, 24], [11, 24], [11, 24], [11, 25], [11, 25], [11, 25], [11, 25], [13, 1664], [13, 1728], [12, 320], [12, 320], [12, 384], [12, 384], [12, 448], [12, 448], [13, 512], [13, 576], [12, 53], [12, 53], [12, 54], [12, 54], [13, 896], [13, 960], [13, 1024], [13, 1088], [13, 1152], [13, 1216], [10, 64], [10, 64], [10, 64], [10, 64], [10, 64], [10, 64], [10, 64], [10, 64]];
const blackTable2 = [[8, 13], [8, 13], [8, 13], [8, 13], [8, 13], [8, 13], [8, 13], [8, 13], [8, 13], [8, 13], [8, 13], [8, 13], [8, 13], [8, 13], [8, 13], [8, 13], [11, 23], [11, 23], [12, 50], [12, 51], [12, 44], [12, 45], [12, 46], [12, 47], [12, 57], [12, 58], [12, 61], [12, 256], [10, 16], [10, 16], [10, 16], [10, 16], [10, 17], [10, 17], [10, 17], [10, 17], [12, 48], [12, 49], [12, 62], [12, 63], [12, 30], [12, 31], [12, 32], [12, 33], [12, 40], [12, 41], [11, 22], [11, 22], [8, 14], [8, 14], [8, 14], [8, 14], [8, 14], [8, 14], [8, 14], [8, 14], [8, 14], [8, 14], [8, 14], [8, 14], [8, 14], [8, 14], [8, 14], [8, 14], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 10], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [7, 11], [9, 15], [9, 15], [9, 15], [9, 15], [9, 15], [9, 15], [9, 15], [9, 15], [12, 128], [12, 192], [12, 26], [12, 27], [12, 28], [12, 29], [11, 19], [11, 19], [11, 20], [11, 20], [12, 34], [12, 35], [12, 36], [12, 37], [12, 38], [12, 39], [11, 21], [11, 21], [12, 42], [12, 43], [10, 0], [10, 0], [10, 0], [10, 0], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12], [7, 12]];
const blackTable3 = [[-1, -1], [-1, -1], [-1, -1], [-1, -1], [6, 9], [6, 8], [5, 7], [5, 7], [4, 6], [4, 6], [4, 6], [4, 6], [4, 5], [4, 5], [4, 5], [4, 5], [3, 1], [3, 1], [3, 1], [3, 1], [3, 1], [3, 1], [3, 1], [3, 1], [3, 4], [3, 4], [3, 4], [3, 4], [3, 4], [3, 4], [3, 4], [3, 4], [2, 3], [2, 3], [2, 3], [2, 3], [2, 3], [2, 3], [2, 3], [2, 3], [2, 3], [2, 3], [2, 3], [2, 3], [2, 3], [2, 3], [2, 3], [2, 3], [2, 2], [2, 2], [2, 2], [2, 2], [2, 2], [2, 2], [2, 2], [2, 2], [2, 2], [2, 2], [2, 2], [2, 2], [2, 2], [2, 2], [2, 2], [2, 2]];

class CCITTFaxDecoder {
  constructor(source, options = {}) {
    if (!source || typeof source.next !== "function") {
      throw new Error('CCITTFaxDecoder - invalid "source" parameter.');
    }

    this.source = source;
    this.eof = false;
    this.encoding = options.K || 0;
    this.eoline = options.EndOfLine || false;
    this.byteAlign = options.EncodedByteAlign || false;
    this.columns = options.Columns || 1728;
    this.rows = options.Rows || 0;
    let eoblock = options.EndOfBlock;

    if (eoblock === null || eoblock === undefined) {
      eoblock = true;
    }

    this.eoblock = eoblock;
    this.black = options.BlackIs1 || false;
    this.codingLine = new Uint32Array(this.columns + 1);
    this.refLine = new Uint32Array(this.columns + 2);
    this.codingLine[0] = this.columns;
    this.codingPos = 0;
    this.row = 0;
    this.nextLine2D = this.encoding < 0;
    this.inputBits = 0;
    this.inputBuf = 0;
    this.outputBits = 0;
    this.rowsDone = false;
    let code1;

    while ((code1 = this._lookBits(12)) === 0) {
      this._eatBits(1);
    }

    if (code1 === 1) {
      this._eatBits(12);
    }

    if (this.encoding > 0) {
      this.nextLine2D = !this._lookBits(1);

      this._eatBits(1);
    }
  }

  readNextChar() {
    if (this.eof) {
      return -1;
    }

    const refLine = this.refLine;
    const codingLine = this.codingLine;
    const columns = this.columns;
    let refPos, blackPixels, bits, i;

    if (this.outputBits === 0) {
      if (this.rowsDone) {
        this.eof = true;
      }

      if (this.eof) {
        return -1;
      }

      this.err = false;
      let code1, code2, code3;

      if (this.nextLine2D) {
        for (i = 0; codingLine[i] < columns; ++i) {
          refLine[i] = codingLine[i];
        }

        refLine[i++] = columns;
        refLine[i] = columns;
        codingLine[0] = 0;
        this.codingPos = 0;
        refPos = 0;
        blackPixels = 0;

        while (codingLine[this.codingPos] < columns) {
          code1 = this._getTwoDimCode();

          switch (code1) {
            case twoDimPass:
              this._addPixels(refLine[refPos + 1], blackPixels);

              if (refLine[refPos + 1] < columns) {
                refPos += 2;
              }

              break;

            case twoDimHoriz:
              code1 = code2 = 0;

              if (blackPixels) {
                do {
                  code1 += code3 = this._getBlackCode();
                } while (code3 >= 64);

                do {
                  code2 += code3 = this._getWhiteCode();
                } while (code3 >= 64);
              } else {
                do {
                  code1 += code3 = this._getWhiteCode();
                } while (code3 >= 64);

                do {
                  code2 += code3 = this._getBlackCode();
                } while (code3 >= 64);
              }

              this._addPixels(codingLine[this.codingPos] + code1, blackPixels);

              if (codingLine[this.codingPos] < columns) {
                this._addPixels(codingLine[this.codingPos] + code2, blackPixels ^ 1);
              }

              while (refLine[refPos] <= codingLine[this.codingPos] && refLine[refPos] < columns) {
                refPos += 2;
              }

              break;

            case twoDimVertR3:
              this._addPixels(refLine[refPos] + 3, blackPixels);

              blackPixels ^= 1;

              if (codingLine[this.codingPos] < columns) {
                ++refPos;

                while (refLine[refPos] <= codingLine[this.codingPos] && refLine[refPos] < columns) {
                  refPos += 2;
                }
              }

              break;

            case twoDimVertR2:
              this._addPixels(refLine[refPos] + 2, blackPixels);

              blackPixels ^= 1;

              if (codingLine[this.codingPos] < columns) {
                ++refPos;

                while (refLine[refPos] <= codingLine[this.codingPos] && refLine[refPos] < columns) {
                  refPos += 2;
                }
              }

              break;

            case twoDimVertR1:
              this._addPixels(refLine[refPos] + 1, blackPixels);

              blackPixels ^= 1;

              if (codingLine[this.codingPos] < columns) {
                ++refPos;

                while (refLine[refPos] <= codingLine[this.codingPos] && refLine[refPos] < columns) {
                  refPos += 2;
                }
              }

              break;

            case twoDimVert0:
              this._addPixels(refLine[refPos], blackPixels);

              blackPixels ^= 1;

              if (codingLine[this.codingPos] < columns) {
                ++refPos;

                while (refLine[refPos] <= codingLine[this.codingPos] && refLine[refPos] < columns) {
                  refPos += 2;
                }
              }

              break;

            case twoDimVertL3:
              this._addPixelsNeg(refLine[refPos] - 3, blackPixels);

              blackPixels ^= 1;

              if (codingLine[this.codingPos] < columns) {
                if (refPos > 0) {
                  --refPos;
                } else {
                  ++refPos;
                }

                while (refLine[refPos] <= codingLine[this.codingPos] && refLine[refPos] < columns) {
                  refPos += 2;
                }
              }

              break;

            case twoDimVertL2:
              this._addPixelsNeg(refLine[refPos] - 2, blackPixels);

              blackPixels ^= 1;

              if (codingLine[this.codingPos] < columns) {
                if (refPos > 0) {
                  --refPos;
                } else {
                  ++refPos;
                }

                while (refLine[refPos] <= codingLine[this.codingPos] && refLine[refPos] < columns) {
                  refPos += 2;
                }
              }

              break;

            case twoDimVertL1:
              this._addPixelsNeg(refLine[refPos] - 1, blackPixels);

              blackPixels ^= 1;

              if (codingLine[this.codingPos] < columns) {
                if (refPos > 0) {
                  --refPos;
                } else {
                  ++refPos;
                }

                while (refLine[refPos] <= codingLine[this.codingPos] && refLine[refPos] < columns) {
                  refPos += 2;
                }
              }

              break;

            case ccittEOF:
              this._addPixels(columns, 0);

              this.eof = true;
              break;

            default:
              (0, _util.info)("bad 2d code");

              this._addPixels(columns, 0);

              this.err = true;
          }
        }
      } else {
        codingLine[0] = 0;
        this.codingPos = 0;
        blackPixels = 0;

        while (codingLine[this.codingPos] < columns) {
          code1 = 0;

          if (blackPixels) {
            do {
              code1 += code3 = this._getBlackCode();
            } while (code3 >= 64);
          } else {
            do {
              code1 += code3 = this._getWhiteCode();
            } while (code3 >= 64);
          }

          this._addPixels(codingLine[this.codingPos] + code1, blackPixels);

          blackPixels ^= 1;
        }
      }

      let gotEOL = false;

      if (this.byteAlign) {
        this.inputBits &= ~7;
      }

      if (!this.eoblock && this.row === this.rows - 1) {
        this.rowsDone = true;
      } else {
        code1 = this._lookBits(12);

        if (this.eoline) {
          while (code1 !== ccittEOF && code1 !== 1) {
            this._eatBits(1);

            code1 = this._lookBits(12);
          }
        } else {
          while (code1 === 0) {
            this._eatBits(1);

            code1 = this._lookBits(12);
          }
        }

        if (code1 === 1) {
          this._eatBits(12);

          gotEOL = true;
        } else if (code1 === ccittEOF) {
          this.eof = true;
        }
      }

      if (!this.eof && this.encoding > 0 && !this.rowsDone) {
        this.nextLine2D = !this._lookBits(1);

        this._eatBits(1);
      }

      if (this.eoblock && gotEOL && this.byteAlign) {
        code1 = this._lookBits(12);

        if (code1 === 1) {
          this._eatBits(12);

          if (this.encoding > 0) {
            this._lookBits(1);

            this._eatBits(1);
          }

          if (this.encoding >= 0) {
            for (i = 0; i < 4; ++i) {
              code1 = this._lookBits(12);

              if (code1 !== 1) {
                (0, _util.info)("bad rtc code: " + code1);
              }

              this._eatBits(12);

              if (this.encoding > 0) {
                this._lookBits(1);

                this._eatBits(1);
              }
            }
          }

          this.eof = true;
        }
      } else if (this.err && this.eoline) {
        while (true) {
          code1 = this._lookBits(13);

          if (code1 === ccittEOF) {
            this.eof = true;
            return -1;
          }

          if (code1 >> 1 === 1) {
            break;
          }

          this._eatBits(1);
        }

        this._eatBits(12);

        if (this.encoding > 0) {
          this._eatBits(1);

          this.nextLine2D = !(code1 & 1);
        }
      }

      if (codingLine[0] > 0) {
        this.outputBits = codingLine[this.codingPos = 0];
      } else {
        this.outputBits = codingLine[this.codingPos = 1];
      }

      this.row++;
    }

    let c;

    if (this.outputBits >= 8) {
      c = this.codingPos & 1 ? 0 : 0xff;
      this.outputBits -= 8;

      if (this.outputBits === 0 && codingLine[this.codingPos] < columns) {
        this.codingPos++;
        this.outputBits = codingLine[this.codingPos] - codingLine[this.codingPos - 1];
      }
    } else {
      bits = 8;
      c = 0;

      do {
        if (typeof this.outputBits !== "number") {
          throw new _util.FormatError('Invalid /CCITTFaxDecode data, "outputBits" must be a number.');
        }

        if (this.outputBits > bits) {
          c <<= bits;

          if (!(this.codingPos & 1)) {
            c |= 0xff >> 8 - bits;
          }

          this.outputBits -= bits;
          bits = 0;
        } else {
          c <<= this.outputBits;

          if (!(this.codingPos & 1)) {
            c |= 0xff >> 8 - this.outputBits;
          }

          bits -= this.outputBits;
          this.outputBits = 0;

          if (codingLine[this.codingPos] < columns) {
            this.codingPos++;
            this.outputBits = codingLine[this.codingPos] - codingLine[this.codingPos - 1];
          } else if (bits > 0) {
            c <<= bits;
            bits = 0;
          }
        }
      } while (bits);
    }

    if (this.black) {
      c ^= 0xff;
    }

    return c;
  }

  _addPixels(a1, blackPixels) {
    const codingLine = this.codingLine;
    let codingPos = this.codingPos;

    if (a1 > codingLine[codingPos]) {
      if (a1 > this.columns) {
        (0, _util.info)("row is wrong length");
        this.err = true;
        a1 = this.columns;
      }

      if (codingPos & 1 ^ blackPixels) {
        ++codingPos;
      }

      codingLine[codingPos] = a1;
    }

    this.codingPos = codingPos;
  }

  _addPixelsNeg(a1, blackPixels) {
    const codingLine = this.codingLine;
    let codingPos = this.codingPos;

    if (a1 > codingLine[codingPos]) {
      if (a1 > this.columns) {
        (0, _util.info)("row is wrong length");
        this.err = true;
        a1 = this.columns;
      }

      if (codingPos & 1 ^ blackPixels) {
        ++codingPos;
      }

      codingLine[codingPos] = a1;
    } else if (a1 < codingLine[codingPos]) {
      if (a1 < 0) {
        (0, _util.info)("invalid code");
        this.err = true;
        a1 = 0;
      }

      while (codingPos > 0 && a1 < codingLine[codingPos - 1]) {
        --codingPos;
      }

      codingLine[codingPos] = a1;
    }

    this.codingPos = codingPos;
  }

  _findTableCode(start, end, table, limit) {
    const limitValue = limit || 0;

    for (let i = start; i <= end; ++i) {
      let code = this._lookBits(i);

      if (code === ccittEOF) {
        return [true, 1, false];
      }

      if (i < end) {
        code <<= end - i;
      }

      if (!limitValue || code >= limitValue) {
        const p = table[code - limitValue];

        if (p[0] === i) {
          this._eatBits(i);

          return [true, p[1], true];
        }
      }
    }

    return [false, 0, false];
  }

  _getTwoDimCode() {
    let code = 0;
    let p;

    if (this.eoblock) {
      code = this._lookBits(7);
      p = twoDimTable[code];

      if (p && p[0] > 0) {
        this._eatBits(p[0]);

        return p[1];
      }
    } else {
      const result = this._findTableCode(1, 7, twoDimTable);

      if (result[0] && result[2]) {
        return result[1];
      }
    }

    (0, _util.info)("Bad two dim code");
    return ccittEOF;
  }

  _getWhiteCode() {
    let code = 0;
    let p;

    if (this.eoblock) {
      code = this._lookBits(12);

      if (code === ccittEOF) {
        return 1;
      }

      if (code >> 5 === 0) {
        p = whiteTable1[code];
      } else {
        p = whiteTable2[code >> 3];
      }

      if (p[0] > 0) {
        this._eatBits(p[0]);

        return p[1];
      }
    } else {
      let result = this._findTableCode(1, 9, whiteTable2);

      if (result[0]) {
        return result[1];
      }

      result = this._findTableCode(11, 12, whiteTable1);

      if (result[0]) {
        return result[1];
      }
    }

    (0, _util.info)("bad white code");

    this._eatBits(1);

    return 1;
  }

  _getBlackCode() {
    let code, p;

    if (this.eoblock) {
      code = this._lookBits(13);

      if (code === ccittEOF) {
        return 1;
      }

      if (code >> 7 === 0) {
        p = blackTable1[code];
      } else if (code >> 9 === 0 && code >> 7 !== 0) {
        p = blackTable2[(code >> 1) - 64];
      } else {
        p = blackTable3[code >> 7];
      }

      if (p[0] > 0) {
        this._eatBits(p[0]);

        return p[1];
      }
    } else {
      let result = this._findTableCode(2, 6, blackTable3);

      if (result[0]) {
        return result[1];
      }

      result = this._findTableCode(7, 12, blackTable2, 64);

      if (result[0]) {
        return result[1];
      }

      result = this._findTableCode(10, 13, blackTable1);

      if (result[0]) {
        return result[1];
      }
    }

    (0, _util.info)("bad black code");

    this._eatBits(1);

    return 1;
  }

  _lookBits(n) {
    let c;

    while (this.inputBits < n) {
      if ((c = this.source.next()) === -1) {
        if (this.inputBits === 0) {
          return ccittEOF;
        }

        return this.inputBuf << n - this.inputBits & 0xffff >> 16 - n;
      }

      this.inputBuf = this.inputBuf << 8 | c;
      this.inputBits += 8;
    }

    return this.inputBuf >> this.inputBits - n & 0xffff >> 16 - n;
  }

  _eatBits(n) {
    if ((this.inputBits -= n) < 0) {
      this.inputBits = 0;
    }
  }

}

exports.CCITTFaxDecoder = CCITTFaxDecoder;