?? jpegfileformat.java
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for (int row = 0; row < 8; row++) { int rIndex = row * DCTSIZE; int tmp0 = dataUnit[rIndex] + dataUnit[rIndex + 7]; int tmp7 = dataUnit[rIndex] - dataUnit[rIndex + 7]; int tmp1 = dataUnit[rIndex + 1] + dataUnit[rIndex + 6]; int tmp6 = dataUnit[rIndex + 1] - dataUnit[rIndex + 6]; int tmp2 = dataUnit[rIndex + 2] + dataUnit[rIndex + 5]; int tmp5 = dataUnit[rIndex + 2] - dataUnit[rIndex + 5]; int tmp3 = dataUnit[rIndex + 3] + dataUnit[rIndex + 4]; int tmp4 = dataUnit[rIndex + 3] - dataUnit[rIndex + 4]; /** * Even part per LL&M figure 1 --- note that published figure * is faulty; rotator 'sqrt(2)*c1' should be 'sqrt(2)*c6'. */ int tmp10 = tmp0 + tmp3; int tmp13 = tmp0 - tmp3; int tmp11 = tmp1 + tmp2; int tmp12 = tmp1 - tmp2; dataUnit[rIndex] = (tmp10 + tmp11) * 4; dataUnit[rIndex + 4] = (tmp10 - tmp11) * 4; int z1 = (tmp12 + tmp13) * FIX_0_541196100; int scaleFactor1 = ExtendTest[11]; int scaleFactor2 = ExtendTest[12]; int n = z1 + (tmp13 * FIX_0_765366865) + scaleFactor1; dataUnit[rIndex + 2] = n / scaleFactor2; if ((n < 0) && (n % scaleFactor2 != 0)) dataUnit[rIndex + 2]--; n = z1 + (tmp12 * (0 - FIX_1_847759065)) + scaleFactor1; dataUnit[rIndex + 6] = n / scaleFactor2; if ((n < 0) && (n % scaleFactor2 != 0)) dataUnit[rIndex + 6]--; /** * Odd part per figure 8 --- note paper omits factor of sqrt(2). * cK represents cos(K*pi/16). * i0..i3 in the paper are tmp4..tmp7 here. */ z1 = tmp4 + tmp7; int z2 = tmp5 + tmp6; int z3 = tmp4 + tmp6; int z4 = tmp5 + tmp7; int z5 = (z3 + z4) * FIX_1_175875602; // sqrt(2) * c3 tmp4 = tmp4 * FIX_0_298631336; // sqrt(2) * (-c1+c3+c5-c7) tmp5 = tmp5 * FIX_2_053119869; // sqrt(2) * ( c1+c3-c5+c7) tmp6 = tmp6 * FIX_3_072711026; // sqrt(2) * ( c1+c3+c5-c7) tmp7 = tmp7 * FIX_1_501321110; // sqrt(2) * ( c1+c3-c5-c7) z1 = z1 * (0 - FIX_0_899976223); // sqrt(2) * (c7-c3) z2 = z2 * (0 - FIX_2_562915447); // sqrt(2) * (-c1-c3) z3 = z3 * (0 - FIX_1_961570560); // sqrt(2) * (-c3-c5) z4 = z4 * (0 - FIX_0_390180644); // sqrt(2) * (c5-c3) z3 = z3 + z5; z4 = z4 + z5; n = tmp4 + z1 + z3 + scaleFactor1; dataUnit[rIndex + 7] = n / scaleFactor2; if ((n < 0) && (n % scaleFactor2 != 0)) dataUnit[rIndex + 7]--; n = tmp5 + z2 + z4 + scaleFactor1; dataUnit[rIndex + 5] = n / scaleFactor2; if ((n < 0) && (n % scaleFactor2 != 0)) dataUnit[rIndex + 5]--; n = tmp6 + z2 + z3 + scaleFactor1; dataUnit[rIndex + 3] = n / scaleFactor2; if ((n < 0) && (n % scaleFactor2 != 0)) dataUnit[rIndex + 3]--; n = tmp7 + z1 + z4 + scaleFactor1; dataUnit[rIndex + 1] = n / scaleFactor2; if ((n < 0) && (n % scaleFactor2 != 0)) dataUnit[rIndex + 1]--; } /** * Pass 2: process columns. * Note that we must descale the results by a factor of 8 == 2**3, * and also undo the PASS1_BITS scaling. */ for (int col = 0; col < 8; col++) { int c0 = col; int c1 = col + 8; int c2 = col + 16; int c3 = col + 24; int c4 = col + 32; int c5 = col + 40; int c6 = col + 48; int c7 = col + 56; int tmp0 = dataUnit[c0] + dataUnit[c7]; int tmp7 = dataUnit[c0] - dataUnit[c7]; int tmp1 = dataUnit[c1] + dataUnit[c6]; int tmp6 = dataUnit[c1] - dataUnit[c6]; int tmp2 = dataUnit[c2] + dataUnit[c5]; int tmp5 = dataUnit[c2] - dataUnit[c5]; int tmp3 = dataUnit[c3] + dataUnit[c4]; int tmp4 = dataUnit[c3] - dataUnit[c4]; /** * Even part per LL&M figure 1 --- note that published figure * is faulty; rotator 'sqrt(2)*c1' should be 'sqrt(2)*c6'. */ int tmp10 = tmp0 + tmp3; int tmp13 = tmp0 - tmp3; int tmp11 = tmp1 + tmp2; int tmp12 = tmp1 - tmp2; int scaleFactor1 = ExtendTest[5]; int scaleFactor2 = ExtendTest[6]; int n = tmp10 + tmp11 + scaleFactor1; dataUnit[c0] = n / scaleFactor2; if ((n < 0) && (n % scaleFactor2 != 0)) dataUnit[c0]--; n = tmp10 - tmp11 + scaleFactor1; dataUnit[c4] = n / scaleFactor2; if ((n < 0) && (n % scaleFactor2 != 0)) dataUnit[c4]--; int z1 = (tmp12 + tmp13) * FIX_0_541196100; scaleFactor1 = ExtendTest[18]; scaleFactor2 = ExtendTest[19]; n = z1 + (tmp13 * FIX_0_765366865) + scaleFactor1; dataUnit[c2] = n / scaleFactor2; if ((n < 0) && (n % scaleFactor2 != 0)) dataUnit[c2]--; n = z1 + (tmp12 * (0 - FIX_1_847759065)) + scaleFactor1; dataUnit[c6] = n / scaleFactor2; if ((n < 0) && (n % scaleFactor2 != 0)) dataUnit[c6]--; /** * Odd part per figure 8 --- note paper omits factor of sqrt(2). * cK represents cos(K*pi/16). * i0..i3 in the paper are tmp4..tmp7 here. */ z1 = tmp4 + tmp7; int z2 = tmp5 + tmp6; int z3 = tmp4 + tmp6; int z4 = tmp5 + tmp7; int z5 = (z3 + z4) * FIX_1_175875602; // sqrt(2) * c3 tmp4 = tmp4 * FIX_0_298631336; // sqrt(2) * (-c1+c3+c5-c7) tmp5 = tmp5 * FIX_2_053119869; // sqrt(2) * ( c1+c3-c5+c7) tmp6 = tmp6 * FIX_3_072711026; // sqrt(2) * ( c1+c3+c5-c7) tmp7 = tmp7 * FIX_1_501321110; // sqrt(2) * ( c1+c3-c5-c7) z1 = z1 * (0 - FIX_0_899976223); // sqrt(2) * (c7-c3) z2 = z2 * (0 - FIX_2_562915447); // sqrt(2) * (-c1-c3) z3 = z3 * (0 - FIX_1_961570560); // sqrt(2) * (-c3-c5) z4 = z4 * (0 - FIX_0_390180644); // sqrt(2) * (c5-c3) z3 = z3 + z5; z4 = z4 + z5; n = tmp4 + z1 + z3 + scaleFactor1; dataUnit[c7] = n / scaleFactor2; if ((n < 0) && (n % scaleFactor2 != 0)) dataUnit[c7]--; n = tmp5 + z2 + z4 + scaleFactor1; dataUnit[c5] = n / scaleFactor2; if ((n < 0) && (n % scaleFactor2 != 0)) dataUnit[c5]--; n = tmp6 + z2 + z3 + scaleFactor1; dataUnit[c3] = n / scaleFactor2; if ((n < 0) && (n % scaleFactor2 != 0)) dataUnit[c3]--; n = tmp7 + z1 + z4 + scaleFactor1; dataUnit[c1] = n / scaleFactor2; if ((n < 0) && (n % scaleFactor2 != 0)) dataUnit[c1]--; }}void getAPP0() { JPEGAppn appn = new JPEGAppn(inputStream); if (!appn.verify()) { SWT.error(SWT.ERROR_INVALID_IMAGE); }}void getCOM() { new JPEGComment(inputStream);}void getDAC() { JPEGArithmeticConditioningTable dac = new JPEGArithmeticConditioningTable(inputStream); arithmeticTables = dac;}void getDHT() { JPEGHuffmanTable dht = new JPEGHuffmanTable(inputStream); if (!dht.verify()) { SWT.error(SWT.ERROR_INVALID_IMAGE); } if (acHuffmanTables == null) { acHuffmanTables = new JPEGHuffmanTable[4]; } if (dcHuffmanTables == null) { dcHuffmanTables = new JPEGHuffmanTable[4]; } JPEGHuffmanTable[] dhtTables = dht.getAllTables(); for (int i = 0; i < dhtTables.length; i++) { JPEGHuffmanTable dhtTable = dhtTables[i]; if (dhtTable.getTableClass() == 0) { dcHuffmanTables[dhtTable.getTableIdentifier()] = dhtTable; } else { acHuffmanTables[dhtTable.getTableIdentifier()] = dhtTable; } }}void getDNL() { new JPEGRestartInterval(inputStream);}void getDQT() { JPEGQuantizationTable dqt = new JPEGQuantizationTable(inputStream); int[][] currentTables = quantizationTables; if (currentTables == null) { currentTables = new int[4][]; } int[] dqtTablesKeys = dqt.getQuantizationTablesKeys(); int[][] dqtTablesValues = dqt.getQuantizationTablesValues(); for (int i = 0; i < dqtTablesKeys.length; i++) { int index = dqtTablesKeys[i]; currentTables[index] = dqtTablesValues[i]; } quantizationTables = currentTables;}void getDRI() { JPEGRestartInterval dri = new JPEGRestartInterval(inputStream); if (!dri.verify()) { SWT.error(SWT.ERROR_INVALID_IMAGE); } restartInterval = dri.getRestartInterval();}static void initialize() { initializeRGBYCbCrTables(); initializeYCbCrRGBTables(); initializeBitCountTable();}static void initializeBitCountTable() { int nBits = 1; int power2 = 2; NBitsTable = new int[2048]; NBitsTable[0] = 0; for (int i = 1; i < NBitsTable.length; i++) { if (!(i < power2)) { nBits++; power2 *= 2; } NBitsTable[i] = nBits; }}static void initializeRGBYCbCrTables() { RYTable = new int[256]; GYTable = new int[256]; BYTable = new int[256]; RCbTable = new int[256]; GCbTable = new int[256]; BCbTable = new int[256]; RCrTable = BCbTable; GCrTable = new int[256]; BCrTable = new int[256]; for (int i = 0; i < 256; i++) { RYTable[i] = i * 19595; GYTable[i] = i * 38470; BYTable[i] = i * 7471 + 32768; RCbTable[i] = i * -11059; GCbTable[i] = i * -21709; BCbTable[i] = i * 32768 + 8388608; GCrTable[i] = i * -27439; BCrTable[i] = i * -5329; }}static void initializeYCbCrRGBTables() { CrRTable = new int[256]; CbBTable = new int[256]; CrGTable = new int[256]; CbGTable = new int[256]; for (int i = 0; i < 256; i++) { int x2 = 2 * i - 255; CrRTable[i] = (45941 * x2 + 32768) / 65536; CbBTable[i] = (58065 * x2 + 32768) / 65536; CrGTable[i] = -23401 * x2; CbGTable[i] = -11277 * x2 + 32768; }}void inverseDCT(int[] dataUnit) { for (int row = 0; row < 8; row++) { int rIndex = row * DCTSIZE; /** * Due to quantization, we will usually find that many of the input * coefficients are zero, especially the AC terms. We can exploit this * by short-circuiting the IDCT calculation for any row in which all * the AC terms are zero. In that case each output is equal to the * DC coefficient (with scale factor as needed). * With typical images and quantization tables, half or more of the * row DCT calculations can be simplified this way. */ if (isZeroInRow(dataUnit, rIndex)) { int dcVal = dataUnit[rIndex] * 4; for (int i = rIndex; i < rIndex + 8; i++) { dataUnit[i] = dcVal; } } else { /** * Even part: reverse the even part of the forward DCT. * The rotator is sqrt(2)*c(-6). */ int z2 = dataUnit[rIndex + 2]; int z3 = dataUnit[rIndex + 6]; int z1 = (z2 + z3) * FIX_0_541196100; int tmp2 = z1 + (z3 * (0 - FIX_1_847759065)); int tmp3 = z1 + (z2 * FIX_0_765366865); int tmp0 = (dataUnit[rIndex] + dataUnit[rIndex + 4]) * 8192; int tmp1 = (dataUnit[rIndex] - dataUnit[rIndex + 4]) * 8192; int tmp10 = tmp0 + tmp3; int tmp13 = tmp0 - tmp3; int tmp11 = tmp1 + tmp2; int tmp12 = tmp1 - tmp2; /** * Odd part per figure 8; the matrix is unitary and hence its * transpose is its inverse. i0..i3 are y7,y5,y3,y1 respectively. */ tmp0 = dataUnit[rIndex + 7]; tmp1 = dataUnit[rIndex + 5]; tmp2 = dataUnit[rIndex + 3]; tmp3 = dataUnit[rIndex + 1]; z1 = tmp0 + tmp3; z2 = tmp1 + tmp2; z3 = tmp0 + tmp2; int z4 = tmp1 + tmp3; int z5 = (z3 + z4)* FIX_1_175875602; /* sqrt(2) * c3 */ tmp0 = tmp0 * FIX_0_298631336; /* sqrt(2) * (-c1+c3+c5-c7) */ tmp1 = tmp1 * FIX_2_053119869; /* sqrt(2) * ( c1+c3-c5+c7) */ tmp2 = tmp2 * FIX_3_072711026; /* sqrt(2) * ( c1+c3+c5-c7) */ tmp3 = tmp3 * FIX_1_501321110; /* sqrt(2) * ( c1+c3-c5-c7) */ z1 = z1 * (0 - FIX_0_899976223); /* sqrt(2) * (c7-c3) */ z2 = z2 * (0 - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */ z3 = z3 * (0 - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */ z4 = z4 * (0 - FIX_0_390180644); /* sqrt(2) * (c5-c3) */ z3 = z3 + z5; z4 = z4 + z5; tmp0 = tmp0 + z1 + z3; tmp1 = tmp1 + z2 + z4; tmp2 = tmp2 + z2 + z3; tmp3 = tmp3 + z1 + z4; int descaleFactor1 = ExtendTest[11]; int descaleFactor2 = ExtendTest[12]; dataUnit[rIndex] = (tmp10 + tmp3 + descaleFactor1) / descaleFactor2; dataUnit[rIndex + 7] = (tmp10 - tmp3 + descaleFactor1) / descaleFactor2; dataUnit[rIndex + 1] = (tmp11 + tmp2 + descaleFactor1) / descaleFactor2; dataUnit[rIndex + 6] = (tmp11 - tmp2 + descaleFactor1) / descaleFactor2; dataUnit[rIndex + 2] = (tmp12 + tmp1 + descaleFactor1) / descaleFactor2; dataUnit[rIndex + 5] = (tmp12 - tmp1 + descaleFactor1) / descaleFactor2; dataUnit[rIndex + 3] = (tmp13 + tmp0 + descaleFactor1) / descaleFactor2; dataUnit[rIndex + 4] = (tmp13 - tmp0 + descaleFactor1) / descaleFactor2; } } /** * Pass 2: process columns. * Note that we must descale the results by a factor of 8 == 2**3, * and also undo the PASS1_BITS scaling. */ for (int col = 0; col < 8; col++) { int c0 = col; int c1 = col + 8; int c2 = col + 16; int c3 = col + 24; int c4 = col + 32; int c5 = col + 40; int c6 = col + 48; int c7 = col + 56; if (isZeroInColumn(dataUnit, col)) { int dcVal = (dataUnit[c0] + 16) / 32; dataUnit[c0] = dcVal; dataUnit[c1] = dcVal; dataUnit[c2] = dcVal; dataUnit[c3] = dcVal; dataUnit[c4] = dcVal; dataUnit[c5] = dcVal; dataUnit[c6] = dcVal; dataUnit[c7] = dcVal; } else { /** * Even part: reverse the even part of the forward DCT. * The rotator is sqrt(2)*c(-6). */ int z2 = dataUnit[c2]; int z3 = dataUnit[c6]; int z1 = (z2 + z3) * FIX_0_541196100; int tmp2 = z1 + (z3 * (0 - FIX_1_847759065)); int tmp3 = z1 + (z2 * FIX_0_765366865); int tmp0 = (dataUnit[c0] + dataUnit[c4]) * 8192; int tmp1 = (dataUnit[c0] - dataUnit[c4]) * 8192; int tmp10 = tmp0 + tmp3; int tmp13 = tmp0 - tmp3; int tmp11 = tmp1 + tmp2; int tmp12 = tmp1 - tmp2; /** * Odd part per figure 8; the matrix is unitary and hence its * transpose is its inverse. i0..i3 are y7,y5,y3,y1 respectively. */ tmp0 = dataUnit[c7]; tmp1 = dataUnit[c5]; tmp2 = dataUnit[c3]; tmp3 = dataUnit[c1]; z1 = tmp0 + tmp3; z2 = tmp1 + tmp2; z3 = tmp0 + tmp2; int z4 = tmp1 + tmp3; int z5 = (z3 + z4) * FIX_1_175875602; /* sqrt(2) * c3 */ tmp0 = tmp0 * FIX_0_298631336; /* sqrt(2) * (-c1+c3+c5-c7) */ tmp1 = tmp1 * FIX_2_053119869; /* sqrt(2) * ( c1+c3-c5+c7) */ tmp2 = tmp2 * FIX_3_072711026; /* sqrt(2) * ( c1+c3+c5-c7) */ tmp3 = tmp3 * FIX_1_501321110; /* sqrt(2) * ( c1+c3-c5-c7) */ z1 = z1 * (0 - FIX_0_899976223); /* sqrt(2) * (c7-c3) */ z2 = z2 * (0 - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */ z3 = z3 * (0 - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */ z4 = z4 * (0 - FIX_0_390180644); /* sqrt(2) * (c5-c3) */ z3 = z3 + z5; z4 = z4 + z5; tmp0 = tmp0 + z1 + z3; tmp1 = tmp1 + z2 + z4; tmp2 = tmp2 + z2 + z3; tmp3 = tmp3 + z1 + z4; /* Final output stage: inputs are tmp10..tmp13, tmp0..tmp3 */ int descaleFactor1 = ExtendTest[18]; int descaleFactor2 = ExtendTest[19]; dataUnit[c0] = (tmp10 + tmp3 + descaleFactor1) / descaleFactor2; dataUnit[c7] = (tmp10 - tmp3 + descaleFactor1) / descaleFactor2; dataUnit[c1] = (tmp11 + tmp2 + descaleFactor1) / descaleFactor2; dataUnit[c6] = (tmp11 - tmp2 + descaleFactor1) / descaleFactor2; dataUnit[c2] = (tmp12 + tmp1 + descaleFactor1) / descaleFactor2; dataUnit[c5] = (tmp12 - tmp1 + descaleFactor1) / descaleFactor2; dataUnit[c3] = (tmp13 + tmp0 + descaleFactor1) / descaleFactor2; dataUnit[c4] = (tmp13 - tmp0 + descaleFactor1) / descaleFactor2; } }}boolean isFileFormat(LEDataInputStream stream) { try { JPEGStartOfImage soi = new JPEGStartOfImage(stream); stream.unread(soi.reference); return soi.verify(); // we no longer check for appN } catch (Exception e) { return false; }}boolean isZeroInColumn(int[] dataUnit, int col) { return (dataUnit[col + 8] + dataUnit[col + 16] + dataUnit[col + 24] + dataUnit[col + 32] + dataUnit[col + 40] + dataUnit[col + 48] + dataUnit[col + 56]) == 0;}boolean isZeroInRow(int[] dataUnit, int rIndex) { return (dataUnit[rIndex + 1] + dataUnit[rIndex + 2] + dataUnit[rIndex + 3] + dataUnit[rIndex + 4] + dataUnit[rIndex + 5] + dataUnit[rIndex + 6] + dataUnit[rIndex + 7]) == 0;}ImageData[] loadFromByteStream() { JPEGStartOfImage soi = new JPEGStartOfImage(inputStream); if (!soi.verify()) SWT.error(SWT.ERROR_INVALID_IMAGE); restartInterval = 0; /* Process the tables preceding the frame header. */ processTables(); /* Start of Frame. */ frameHeader = new JPEGFrameHeader(inputStream); if (!frameHeader.verify()) SWT.error(SWT.ERROR_INVALID_IMAGE); imageWidth = frameHeader.getSamplesPerLine(); imageHeight = frameHeader.getNumberOfLines(); maxH = frameHeader.getMaxHFactor(); maxV = frameHeader.getMaxVFactor(); int mcuWidth = maxH * DCTSIZE; int mcuHeight = maxV * DCTSIZE; interleavedMcuCols = (imageWidth + mcuWidth - 1) / mcuWidth; interleavedMcuRows = (imageHeight + mcuHeight - 1) / mcuHeight; progressive = frameHeader.isProgressive(); samplePrecision = frameHeader.getSamplePrecision(); nComponents = frameHeader.getNumberOfImageComponents(); frameComponents = frameHeader.componentParameters; componentIds = frameHeader.componentIdentifiers; imageComponents = new byte[nComponents][]; if (progressive) {?? 快捷鍵說明
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