tifffaxdecoder.java

源码包含生成 PDF 和 HTML 的类库

        232,    232,    232,    232,    232,    232,    232,    232,
        // 984 - 991
        232,    232,    232,    232,    232,    232,    232,    232,
        // 992 - 999
        232,    232,    232,    232,    232,    232,    232,    232,
        // 1000 - 1007
        232,    232,    232,    232,    232,    232,    232,    232,
        // 1008 - 1015
        232,    232,    232,    232,    232,    232,    232,    232,
        // 1016 - 1023
        232,    232,    232,    232,    232,    232,    232,    232,
    };
    
    // Additional make up codes for both White and Black runs
    static short additionalMakeup[] = {
        28679,  28679,  31752,  (short)32777,
        (short)33801,  (short)34825,  (short)35849,  (short)36873,
        (short)29703,  (short)29703,  (short)30727,  (short)30727,
        (short)37897,  (short)38921,  (short)39945,  (short)40969
    };
    
    // Initial black run look up table, uses the first 4 bits of a code
    static short initBlack[] = {
        // 0 - 7
        3226,  6412,    200,    168,    38,     38,    134,    134,
        // 8 - 15
        100,    100,    100,    100,    68,     68,     68,     68
    };
    
    //
    static short twoBitBlack[] = {292, 260, 226, 226};   // 0 - 3
    
    // Main black run table, using the last 9 bits of possible 13 bit code
    static short black[] = {
        // 0 - 7
        62,     62,     30,     30,     0,      0,      0,      0,
        // 8 - 15
        0,      0,      0,      0,      0,      0,      0,      0,
        // 16 - 23
        0,      0,      0,      0,      0,      0,      0,      0,
        // 24 - 31
        0,      0,      0,      0,      0,      0,      0,      0,
        // 32 - 39
        3225,   3225,   3225,   3225,   3225,   3225,   3225,   3225,
        // 40 - 47
        3225,   3225,   3225,   3225,   3225,   3225,   3225,   3225,
        // 48 - 55
        3225,   3225,   3225,   3225,   3225,   3225,   3225,   3225,
        // 56 - 63
        3225,   3225,   3225,   3225,   3225,   3225,   3225,   3225,
        // 64 - 71
        588,    588,    588,    588,    588,    588,    588,    588,
        // 72 - 79
        1680,   1680,  20499,  22547,  24595,  26643,   1776,   1776,
        // 80 - 87
        1808,   1808, -24557, -22509, -20461, -18413,   1904,   1904,
        // 88 - 95
        1936,   1936, -16365, -14317,    782,    782,    782,    782,
        // 96 - 103
        814,    814,    814,    814, -12269, -10221,  10257,  10257,
        // 104 - 111
        12305,  12305,  14353,  14353,  16403,  18451,   1712,   1712,
        // 112 - 119
        1744,   1744,  28691,  30739, -32749, -30701, -28653, -26605,
        // 120 - 127
        2061,   2061,   2061,   2061,   2061,   2061,   2061,   2061,
        // 128 - 135
        424,    424,    424,    424,    424,    424,    424,    424,
        // 136 - 143
        424,    424,    424,    424,    424,    424,    424,    424,
        // 144 - 151
        424,    424,    424,    424,    424,    424,    424,    424,
        // 152 - 159
        424,    424,    424,    424,    424,    424,    424,    424,
        // 160 - 167
        750,    750,    750,    750,   1616,   1616,   1648,   1648,
        // 168 - 175
        1424,   1424,   1456,   1456,   1488,   1488,   1520,   1520,
        // 176 - 183
        1840,   1840,   1872,   1872,   1968,   1968,   8209,   8209,
        // 184 - 191
        524,    524,    524,    524,    524,    524,    524,    524,
        // 192 - 199
        556,    556,    556,    556,    556,    556,    556,    556,
        // 200 - 207
        1552,   1552,   1584,   1584,   2000,   2000,   2032,   2032,
        // 208 - 215
        976,    976,   1008,   1008,   1040,   1040,   1072,   1072,
        // 216 - 223
        1296,   1296,   1328,   1328,    718,    718,    718,    718,
        // 224 - 231
        456,    456,    456,    456,    456,    456,    456,    456,
        // 232 - 239
        456,    456,    456,    456,    456,    456,    456,    456,
        // 240 - 247
        456,    456,    456,    456,    456,    456,    456,    456,
        // 248 - 255
        456,    456,    456,    456,    456,    456,    456,    456,
        // 256 - 263
        326,    326,    326,    326,    326,    326,    326,    326,
        // 264 - 271
        326,    326,    326,    326,    326,    326,    326,    326,
        // 272 - 279
        326,    326,    326,    326,    326,    326,    326,    326,
        // 280 - 287
        326,    326,    326,    326,    326,    326,    326,    326,
        // 288 - 295
        326,    326,    326,    326,    326,    326,    326,    326,
        // 296 - 303
        326,    326,    326,    326,    326,    326,    326,    326,
        // 304 - 311
        326,    326,    326,    326,    326,    326,    326,    326,
        // 312 - 319
        326,    326,    326,    326,    326,    326,    326,    326,
        // 320 - 327
        358,    358,    358,    358,    358,    358,    358,    358,
        // 328 - 335
        358,    358,    358,    358,    358,    358,    358,    358,
        // 336 - 343
        358,    358,    358,    358,    358,    358,    358,    358,
        // 344 - 351
        358,    358,    358,    358,    358,    358,    358,    358,
        // 352 - 359
        358,    358,    358,    358,    358,    358,    358,    358,
        // 360 - 367
        358,    358,    358,    358,    358,    358,    358,    358,
        // 368 - 375
        358,    358,    358,    358,    358,    358,    358,    358,
        // 376 - 383
        358,    358,    358,    358,    358,    358,    358,    358,
        // 384 - 391
        490,    490,    490,    490,    490,    490,    490,    490,
        // 392 - 399
        490,    490,    490,    490,    490,    490,    490,    490,
        // 400 - 407
        4113,   4113,   6161,   6161,    848,    848,    880,    880,
        // 408 - 415
        912,    912,    944,    944,    622,    622,    622,    622,
        // 416 - 423
        654,    654,    654,    654,   1104,   1104,   1136,   1136,
        // 424 - 431
        1168,   1168,   1200,   1200,   1232,   1232,   1264,   1264,
        // 432 - 439
        686,    686,    686,    686,   1360,   1360,   1392,   1392,
        // 440 - 447
        12,     12,     12,     12,     12,     12,     12,     12,
        // 448 - 455
        390,    390,    390,    390,    390,    390,    390,    390,
        // 456 - 463
        390,    390,    390,    390,    390,    390,    390,    390,
        // 464 - 471
        390,    390,    390,    390,    390,    390,    390,    390,
        // 472 - 479
        390,    390,    390,    390,    390,    390,    390,    390,
        // 480 - 487
        390,    390,    390,    390,    390,    390,    390,    390,
        // 488 - 495
        390,    390,    390,    390,    390,    390,    390,    390,
        // 496 - 503
        390,    390,    390,    390,    390,    390,    390,    390,
        // 504 - 511
        390,    390,    390,    390,    390,    390,    390,    390,
    };
    
    static byte twoDCodes[] = {
        // 0 - 7
        80,     88,     23,     71,     30,     30,     62,     62,
        // 8 - 15
        4,      4,      4,      4,      4,      4,      4,      4,
        // 16 - 23
        11,     11,     11,     11,     11,     11,     11,     11,
        // 24 - 31
        11,     11,     11,     11,     11,     11,     11,     11,
        // 32 - 39
        35,     35,     35,     35,     35,     35,     35,     35,
        // 40 - 47
        35,     35,     35,     35,     35,     35,     35,     35,
        // 48 - 55
        51,     51,     51,     51,     51,     51,     51,     51,
        // 56 - 63
        51,     51,     51,     51,     51,     51,     51,     51,
        // 64 - 71
        41,     41,     41,     41,     41,     41,     41,     41,
        // 72 - 79
        41,     41,     41,     41,     41,     41,     41,     41,
        // 80 - 87
        41,     41,     41,     41,     41,     41,     41,     41,
        // 88 - 95
        41,     41,     41,     41,     41,     41,     41,     41,
        // 96 - 103
        41,     41,     41,     41,     41,     41,     41,     41,
        // 104 - 111
        41,     41,     41,     41,     41,     41,     41,     41,
        // 112 - 119
        41,     41,     41,     41,     41,     41,     41,     41,
        // 120 - 127
        41,     41,     41,     41,     41,     41,     41,     41,
    };
    
    /**
     * @param fillOrder   The fill order of the compressed data bytes.
     * @param w
     * @param h
     */
    public TIFFFaxDecoder(int fillOrder, int w, int h) {
        this.fillOrder = fillOrder;
        this.w = w;
        this.h = h;
        
        this.bitPointer = 0;
        this.bytePointer = 0;
        this.prevChangingElems = new int[w];
        this.currChangingElems = new int[w];
    }
    
    /**
      * Reverses the bits in the array
      * @param b the bits to reverse
      *
      * @since 2.0.7
     */
    public static void reverseBits(byte[] b) {
        for (int k = 0; k < b.length; ++k)
            b[k] = flipTable[b[k] & 0xff];
    }

    // One-dimensional decoding methods
    
    public void decode1D(byte[] buffer, byte[] compData,
    int startX, int height) {
        this.data = compData;
        
        int lineOffset = 0;
        int scanlineStride = (w + 7)/8;
        
        bitPointer = 0;
        bytePointer = 0;
        
        for (int i = 0; i < height; i++) {
            decodeNextScanline(buffer, lineOffset, startX);
            lineOffset += scanlineStride;
        }
    }
    
    public void decodeNextScanline(byte[] buffer,
    int lineOffset, int bitOffset) {
        int bits = 0, code = 0, isT = 0;
        int current, entry, twoBits;
        boolean isWhite = true;
        
        // Initialize starting of the changing elements array
        changingElemSize = 0;
        
        // While scanline not complete
        while (bitOffset < w) {
            while (isWhite) {
                // White run
                current = nextNBits(10);
                entry = white[current];
                
                // Get the 3 fields from the entry
                isT = entry & 0x0001;
                bits = (entry >>> 1) & 0x0f;
                
                if (bits == 12) {          // Additional Make up code
                    // Get the next 2 bits
                    twoBits = nextLesserThan8Bits(2);
                    // Consolidate the 2 new bits and last 2 bits into 4 bits
                    current = ((current << 2) & 0x000c) | twoBits;
                    entry = additionalMakeup[current];
                    bits = (entry >>> 1) & 0x07;     // 3 bits 0000 0111
                    code  = (entry >>> 4) & 0x0fff;  // 12 bits
                    bitOffset += code; // Skip white run
                    
                    updatePointer(4 - bits);
                } else if (bits == 0) {     // ERROR
                    throw new RuntimeException("Invalid code encountered.");
                } else if (bits == 15) {    // EOL
                    throw new RuntimeException("EOL code word encountered in White run.");
                } else {
                    // 11 bits - 0000 0111 1111 1111 = 0x07ff
                    code = (entry >>> 5) & 0x07ff;
                    bitOffset += code;
                    
                    updatePointer(10 - bits);
                    if (isT == 0) {
                        isWhite = false;
                        currChangingElems[changingElemSize++] = bitOffset;
                    }
                }
            }
            
            // Check whether this run completed one width, if so
            // advance to next byte boundary for compression = 2.
            if (bitOffset == w) {
                if (compression == 2) {
                    advancePointer();
                }
                break;
            }
            
            while (!isWhite) {
                // Black run
                current = nextLesserThan8Bits(4);
                entry = initBlack[current];
                
                // Get the 3 fields from the entry
                isT = entry & 0x0001;
                bits = (entry >>> 1) & 0x000f;
                code = (entry >>> 5) & 0x07ff;
                
                if (code == 100) {
                    current = nextNBits(9);
                    entry = black[current];
                    
                    // Get the 3 fields from the entry
                    isT = entry & 0x0001;
                    bits = (entry >>> 1) & 0x000f;
                    code = (entry >>> 5) & 0x07ff;
                    
                    if (bits == 12) {
                        // Additional makeup codes
                        updatePointer(5);
                        current = nextLesserThan8Bits(4);
                        entry = additionalMakeup[current];
                        bits = (entry >>> 1) & 0x07;     // 3 bits 0000 0111
                        code  = (entry >>> 4) & 0x0fff;  // 12 bits
                        
                        setToBlack(buffer, lineOffset, bitOffset, code);
                        bitOffset += code;
                        
                        updatePointer(4 - bits);
                    } else if (bits == 15) {
                        // EOL code
                        throw new RuntimeException("EOL code word encountered in Black run.");
                    } else {
                        setToBlack(buffer, lineOffset, bitOffset, code);
                        bitOffset += code;
                        
                        updatePointer(9 - bits);
                        if (isT == 0) {
                            isWhite = true;
                            currChangingElems[changingElemSize++] = bitOffset;
                        }
                    }
                } else if (code == 200) {
                    // Is a Terminating code
                    current = nextLesserThan8Bits(2);
                    entry = twoBitBlack[current];
                    code = (entry >>> 5) & 0x07ff;
                    bits = (entry >>> 1) & 0x0f;
                    
                    setToBlack(buffer, lineOffset, bitOffset, code);
                    bitOffset += code;
                    
                    updatePointer(2 - bits);
                    isWhite = true;
                    currChangingElems[changingElemSize++] = bitOffset;
                } else {
                    // Is a Terminating code
                    setToBlack(buffer, lineOffset, bitOffset, code);
                    bitOffset += code;
                    
                    updatePointer(4 - bits);
                    isWhite = true;
                    currChangingElems[changingElemSize++] = bitOffset;
                }
            }
            
            // Check whether this run completed one width
            if (bitOffset == w) {
                if (compression == 2) {
                    advancePointer();
                }
                break;
            }
        }