/// <summary>
/// Inverse DCT, de-quantization and level shift part of the JPEG decoding.
/// Input is expected in 64x1 macro blocks and output is expected to be in 8x8
/// macro blocks.
/// </summary>
/// <param name="src">Source image.</param>
/// <param name="dst">Destination image</param>
/// <param name="QuantInvTable">Inverse quantization tables for JPEG decoding created using QuantInvTableInit()</param>
/// <param name="oSizeRoi">Roi size (in macro blocks?).</param>
public static void DCTQuantInv8x8LS(NPPImage_16sC1 src, NPPImage_8uC1 dst, CudaDeviceVariable <ushort> QuantInvTable, NppiSize oSizeRoi)
{
NppStatus status;
status = NPPNativeMethods.NPPi.ImageCompression.nppiDCTQuantInv8x8LS_JPEG_16s8u_C1R(src.DevicePointer, src.Pitch, dst.DevicePointer, dst.Pitch, QuantInvTable.DevicePointer, oSizeRoi);
Debug.WriteLine(String.Format("{0:G}, {1}: {2}", DateTime.Now, "nppiDCTQuantInv8x8LS_JPEG_16s8u_C1R", status));
NPPException.CheckNppStatus(status, null);
}
/// <summary>
/// Huffman Encoding of the JPEG Encoding.<para/>
/// Input is expected to be 64x1 macro blocks and output is expected as byte stuffed huffman encoded JPEG scan.
/// </summary>
/// <param name="pSrc">Source image.</param>
/// <param name="restartInterval">Restart Interval, see JPEG standard.</param>
/// <param name="Ss">Start Coefficient, see JPEG standard.</param>
/// <param name="Se">End Coefficient, see JPEG standard.</param>
/// <param name="Ah">Bit Approximation High, see JPEG standard.</param>
/// <param name="Al">Bit Approximation Low, see JPEG standard.</param>
/// <param name="pDst">Byte-stuffed huffman encoded JPEG scan.</param>
/// <param name="nLength">Byte length of the huffman encoded JPEG scan.</param>
/// <param name="pHuffmanTableDC">DC Huffman table.</param>
/// <param name="pHuffmanTableAC">AC Huffman table.</param>
/// <param name="oSizeROI">ROI</param>
/// <param name="buffer">Scratch buffer</param>
public static void EncodeHuffmanScan(NPPImage_16sC1 pSrc, int restartInterval, int Ss, int Se, int Ah, int Al,
CudaDeviceVariable <byte> pDst, ref int nLength, NppiEncodeHuffmanSpec pHuffmanTableDC, NppiEncodeHuffmanSpec pHuffmanTableAC, NppiSize oSizeROI, CudaDeviceVariable <byte> buffer)
{
NppStatus status;
status = NPPNativeMethods.NPPi.CompressionDCT.nppiEncodeHuffmanScan_JPEG_8u16s_P1R(pSrc.DevicePointer, pSrc.Pitch, restartInterval, Ss, Se, Ah, Al, pDst.DevicePointer, ref nLength, pHuffmanTableDC, pHuffmanTableAC, oSizeROI, buffer.DevicePointer);
Debug.WriteLine(String.Format("{0:G}, {1}: {2}", DateTime.Now, "nppiEncodeHuffmanScan_JPEG_8u16s_P1R", status));
NPPException.CheckNppStatus(status, null);
}
/// <summary>
/// 32-bit unsigned to 16-bit signed conversion.
/// </summary>
/// <param name="dst">Destination image</param>
/// <param name="roundMode">Round mode</param>
/// <param name="scaleFactor">scaling factor</param>
public void Convert(NPPImage_16sC1 dst, NppRoundMode roundMode, int scaleFactor)
{
status = NPPNativeMethods.NPPi.BitDepthConversion.nppiConvert_32u16s_C1RSfs(_devPtrRoi, _pitch, dst.DevicePointerRoi, dst.Pitch, _sizeRoi, roundMode, scaleFactor);
Debug.WriteLine(String.Format("{0:G}, {1}: {2}", DateTime.Now, "nppiConvert_32u16s_C1RSfs", status));
NPPException.CheckNppStatus(status, this);
}
/// <summary>
/// Inverse DCT in WebP decoding. Input is the bitstream that contains the coefficients of 16x16 blocks.
/// These coefficients are based on a 4x4 sub-block unit, e.g.,
/// Coeffs in 0th 4x4 block, 1st 4x4 block 2nd 4x4 block, etc.
/// Output is the coefficients after inverse DCT transform.
/// The output is put in an image format (i.e. raster scan order), different from the input order.
/// </summary>
/// <param name="src">Source image.</param>
/// <param name="dst">Destination image</param>
/// <param name="oSizeRoi">Roi size (in pixels).</param>
public void DCTQuant16Fwd8x8LS(NPPImage_16sC1 src, NPPImage_16sC1 dst, NppiSize oSizeRoi)
{
status = NPPNativeMethods.NPPi.CompressionDCT.nppiDCTInv4x4_WebP_16s_C1R(src.DevicePointer, src.Pitch, dst.DevicePointer, dst.Pitch, oSizeRoi);
Debug.WriteLine(String.Format("{0:G}, {1}: {2}", DateTime.Now, "nppiDCTInv4x4_WebP_16s_C1R", status));
NPPException.CheckNppStatus(status, this);
}
/// <summary>
/// Inverse DCT, de-quantization and level shift part of the JPEG decoding, 16-bit short integer.
/// Input is expected in 64x1 macro blocks and output is expected to be in 8x8
/// macro blocks. The new version of the primitive takes the ROI in image pixel size and
/// works with DCT coefficients that are in zig-zag order.
/// </summary>
/// <param name="src">Source image.</param>
/// <param name="dst">Destination image</param>
/// <param name="pQuantizationTable">Quantization Table in zig-zag order.</param>
/// <param name="oSizeRoi">Roi size (in pixels).</param>
public void DCTQuant16Inv8x8LS(NPPImage_16sC1 src, NPPImage_8uC1 dst, NppiSize oSizeRoi, CudaDeviceVariable <ushort> pQuantizationTable)
{
status = NPPNativeMethods.NPPi.CompressionDCT.nppiDCTQuant16Inv8x8LS_JPEG_16s8u_C1R_NEW(src.DevicePointer, src.Pitch, dst.DevicePointer, dst.Pitch, pQuantizationTable.DevicePointer, oSizeRoi, _state);
Debug.WriteLine(String.Format("{0:G}, {1}: {2}", DateTime.Now, "nppiDCTQuant16Inv8x8LS_JPEG_16s8u_C1R_NEW", status));
NPPException.CheckNppStatus(status, this);
}
public static void SaveJpeg(string aFilename, int aQuality, Bitmap aImage)
{
if (aImage.PixelFormat != System.Drawing.Imaging.PixelFormat.Format24bppRgb)
{
throw new ArgumentException("Only three channel color images are supported.");
}
if (aImage.Width % 16 != 0 || aImage.Height % 16 != 0)
{
throw new ArgumentException("The provided bitmap must have a height and width of a multiple of 16.");
}
JPEGCompression compression = new JPEGCompression();
NPPImage_8uC3 src = new NPPImage_8uC3(aImage.Width, aImage.Height);
NPPImage_8uC1 srcY = new NPPImage_8uC1(aImage.Width, aImage.Height);
NPPImage_8uC1 srcCb = new NPPImage_8uC1(aImage.Width / 2, aImage.Height / 2);
NPPImage_8uC1 srcCr = new NPPImage_8uC1(aImage.Width / 2, aImage.Height / 2);
src.CopyToDevice(aImage);
//System.Drawing.Bitmap is ordered BGR not RGB
//The NPP routine BGR to YCbCR outputs the values in clamped range, following the YCbCr standard.
//But JPEG uses unclamped values ranging all from [0..255], thus use our own color matrix:
float[,] BgrToYCbCr = new float[3, 4]
{
{ 0.114f, 0.587f, 0.299f, 0 },
{ 0.5f, -0.33126f, -0.16874f, 128 },
{ -0.08131f, -0.41869f, 0.5f, 128 }
};
src.ColorTwist(BgrToYCbCr);
//Reduce size of of Cb and Cr channel
src.Copy(srcY, 2);
srcY.Resize(srcCr, 0.5, 0.5, InterpolationMode.SuperSampling);
src.Copy(srcY, 1);
srcY.Resize(srcCb, 0.5, 0.5, InterpolationMode.SuperSampling);
src.Copy(srcY, 0);
FrameHeader oFrameHeader = new FrameHeader();
oFrameHeader.nComponents = 3;
oFrameHeader.nHeight = (ushort)aImage.Height;
oFrameHeader.nSamplePrecision = 8;
oFrameHeader.nWidth = (ushort)aImage.Width;
oFrameHeader.aComponentIdentifier = new byte[] { 1, 2, 3 };
oFrameHeader.aSamplingFactors = new byte[] { 34, 17, 17 }; //Y channel is twice the sice of Cb/Cr channel
oFrameHeader.aQuantizationTableSelector = new byte[] { 0, 1, 1 };
//Get quantization tables from JPEG standard with quality scaling
QuantizationTable[] aQuantizationTables = new QuantizationTable[2];
aQuantizationTables[0] = new QuantizationTable(QuantizationTable.QuantizationType.Luminance, aQuality);
aQuantizationTables[1] = new QuantizationTable(QuantizationTable.QuantizationType.Chroma, aQuality);
CudaDeviceVariable <byte>[] pdQuantizationTables = new CudaDeviceVariable <byte> [2];
pdQuantizationTables[0] = aQuantizationTables[0].aTable;
pdQuantizationTables[1] = aQuantizationTables[1].aTable;
//Get Huffman tables from JPEG standard
HuffmanTable[] aHuffmanTables = new HuffmanTable[4];
aHuffmanTables[0] = new HuffmanTable(HuffmanTable.HuffmanType.LuminanceDC);
aHuffmanTables[1] = new HuffmanTable(HuffmanTable.HuffmanType.ChromaDC);
aHuffmanTables[2] = new HuffmanTable(HuffmanTable.HuffmanType.LuminanceAC);
aHuffmanTables[3] = new HuffmanTable(HuffmanTable.HuffmanType.ChromaAC);
//Set header
ScanHeader oScanHeader = new ScanHeader();
oScanHeader.nA = 0;
oScanHeader.nComponents = 3;
oScanHeader.nSe = 63;
oScanHeader.nSs = 0;
oScanHeader.aComponentSelector = new byte[] { 1, 2, 3 };
oScanHeader.aHuffmanTablesSelector = new byte[] { 0, 17, 17 };
NPPImage_16sC1[] apdDCT = new NPPImage_16sC1[3];
NPPImage_8uC1[] apDstImage = new NPPImage_8uC1[3];
NppiSize[] aDstSize = new NppiSize[3];
aDstSize[0] = new NppiSize(srcY.Width, srcY.Height);
aDstSize[1] = new NppiSize(srcCb.Width, srcCb.Height);
aDstSize[2] = new NppiSize(srcCr.Width, srcCr.Height);
// Compute channel sizes as stored in the output JPEG (8x8 blocks & MCU block layout)
NppiSize oDstImageSize = new NppiSize();
float frameWidth = (float)Math.Floor((float)oFrameHeader.nWidth);
float frameHeight = (float)Math.Floor((float)oFrameHeader.nHeight);
oDstImageSize.width = (int)Math.Max(1.0f, frameWidth);
oDstImageSize.height = (int)Math.Max(1.0f, frameHeight);
//Console.WriteLine("Output Size: " + oDstImageSize.width + "x" + oDstImageSize.height + "x" + (int)(oFrameHeader.nComponents));
apDstImage[0] = srcY;
apDstImage[1] = srcCb;
apDstImage[2] = srcCr;
int nMCUBlocksH = 0;
int nMCUBlocksV = 0;
// Compute channel sizes as stored in the JPEG (8x8 blocks & MCU block layout)
for (int i = 0; i < oFrameHeader.nComponents; ++i)
{
nMCUBlocksV = Math.Max(nMCUBlocksV, oFrameHeader.aSamplingFactors[i] >> 4);
nMCUBlocksH = Math.Max(nMCUBlocksH, oFrameHeader.aSamplingFactors[i] & 0x0f);
}
for (int i = 0; i < oFrameHeader.nComponents; ++i)
{
NppiSize oBlocks = new NppiSize();
NppiSize oBlocksPerMCU = new NppiSize(oFrameHeader.aSamplingFactors[i] & 0x0f, oFrameHeader.aSamplingFactors[i] >> 4);
oBlocks.width = (int)Math.Ceiling((oFrameHeader.nWidth + 7) / 8 *
(float)(oBlocksPerMCU.width) / nMCUBlocksH);
oBlocks.width = DivUp(oBlocks.width, oBlocksPerMCU.width) * oBlocksPerMCU.width;
oBlocks.height = (int)Math.Ceiling((oFrameHeader.nHeight + 7) / 8 *
(float)(oBlocksPerMCU.height) / nMCUBlocksV);
oBlocks.height = DivUp(oBlocks.height, oBlocksPerMCU.height) * oBlocksPerMCU.height;
// Allocate Memory
apdDCT[i] = new NPPImage_16sC1(oBlocks.width * 64, oBlocks.height);
}
/***************************
*
* Output
*
***************************/
// Forward DCT
for (int i = 0; i < 3; ++i)
{
compression.DCTQuantFwd8x8LS(apDstImage[i], apdDCT[i], aDstSize[i], pdQuantizationTables[oFrameHeader.aQuantizationTableSelector[i]]);
}
// Huffman Encoding
CudaDeviceVariable <byte> pdScan = new CudaDeviceVariable <byte>(BUFFER_SIZE);
int nScanLength = 0;
int nTempSize = JPEGCompression.EncodeHuffmanGetSize(aDstSize[0], 3);
CudaDeviceVariable <byte> pJpegEncoderTemp = new CudaDeviceVariable <byte>(nTempSize);
NppiEncodeHuffmanSpec[] apHuffmanDCTableEnc = new NppiEncodeHuffmanSpec[3];
NppiEncodeHuffmanSpec[] apHuffmanACTableEnc = new NppiEncodeHuffmanSpec[3];
for (int i = 0; i < 3; ++i)
{
apHuffmanDCTableEnc[i] = JPEGCompression.EncodeHuffmanSpecInitAlloc(aHuffmanTables[(oScanHeader.aHuffmanTablesSelector[i] >> 4)].aCodes, NppiHuffmanTableType.nppiDCTable);
apHuffmanACTableEnc[i] = JPEGCompression.EncodeHuffmanSpecInitAlloc(aHuffmanTables[(oScanHeader.aHuffmanTablesSelector[i] & 0x0f) + 2].aCodes, NppiHuffmanTableType.nppiACTable);
}
JPEGCompression.EncodeHuffmanScan(apdDCT, 0, oScanHeader.nSs, oScanHeader.nSe, oScanHeader.nA >> 4, oScanHeader.nA & 0x0f, pdScan, ref nScanLength, apHuffmanDCTableEnc, apHuffmanACTableEnc, aDstSize, pJpegEncoderTemp);
for (int i = 0; i < 3; ++i)
{
JPEGCompression.EncodeHuffmanSpecFree(apHuffmanDCTableEnc[i]);
JPEGCompression.EncodeHuffmanSpecFree(apHuffmanACTableEnc[i]);
}
// Write JPEG to byte array, as in original sample code
byte[] pDstOutput = new byte[BUFFER_SIZE];
int pos = 0;
oFrameHeader.nWidth = (ushort)oDstImageSize.width;
oFrameHeader.nHeight = (ushort)oDstImageSize.height;
writeMarker(0x0D8, pDstOutput, ref pos);
writeJFIFTag(pDstOutput, ref pos);
writeQuantizationTable(aQuantizationTables[0], pDstOutput, ref pos);
writeQuantizationTable(aQuantizationTables[1], pDstOutput, ref pos);
writeFrameHeader(oFrameHeader, pDstOutput, ref pos);
writeHuffmanTable(aHuffmanTables[0], pDstOutput, ref pos);
writeHuffmanTable(aHuffmanTables[1], pDstOutput, ref pos);
writeHuffmanTable(aHuffmanTables[2], pDstOutput, ref pos);
writeHuffmanTable(aHuffmanTables[3], pDstOutput, ref pos);
writeScanHeader(oScanHeader, pDstOutput, ref pos);
pdScan.CopyToHost(pDstOutput, 0, pos, nScanLength);
pos += nScanLength;
writeMarker(0x0D9, pDstOutput, ref pos);
FileStream fs = new FileStream(aFilename, FileMode.Create, FileAccess.Write);
fs.Write(pDstOutput, 0, pos);
fs.Close();
//cleanup:
fs.Dispose();
pJpegEncoderTemp.Dispose();
pdScan.Dispose();
apdDCT[2].Dispose();
apdDCT[1].Dispose();
apdDCT[0].Dispose();
pdQuantizationTables[1].Dispose();
pdQuantizationTables[0].Dispose();
srcCr.Dispose();
srcCb.Dispose();
srcY.Dispose();
src.Dispose();
compression.Dispose();
}
public static Bitmap LoadJpeg(string aFilename)
{
JPEGCompression compression = new JPEGCompression();
byte[] pJpegData = File.ReadAllBytes(aFilename);
int nInputLength = pJpegData.Length;
// Check if this is a valid JPEG file
int nPos = 0;
int nMarker = nextMarker(pJpegData, ref nPos, nInputLength);
if (nMarker != 0x0D8)
{
throw new ArgumentException(aFilename + " is not a JPEG file.");
}
nMarker = nextMarker(pJpegData, ref nPos, nInputLength);
// Parsing and Huffman Decoding (on host)
FrameHeader oFrameHeader = new FrameHeader();
oFrameHeader.aComponentIdentifier = new byte[3];
oFrameHeader.aSamplingFactors = new byte[3];
oFrameHeader.aQuantizationTableSelector = new byte[3];
QuantizationTable[] aQuantizationTables = new QuantizationTable[4];
aQuantizationTables[0] = new QuantizationTable();
aQuantizationTables[1] = new QuantizationTable();
aQuantizationTables[2] = new QuantizationTable();
aQuantizationTables[3] = new QuantizationTable();
CudaDeviceVariable <byte>[] pdQuantizationTables = new CudaDeviceVariable <byte> [4];
pdQuantizationTables[0] = new CudaDeviceVariable <byte>(64);
pdQuantizationTables[1] = new CudaDeviceVariable <byte>(64);
pdQuantizationTables[2] = new CudaDeviceVariable <byte>(64);
pdQuantizationTables[3] = new CudaDeviceVariable <byte>(64);
HuffmanTable[] aHuffmanTables = new HuffmanTable[4];
aHuffmanTables[0] = new HuffmanTable();
aHuffmanTables[1] = new HuffmanTable();
aHuffmanTables[2] = new HuffmanTable();
aHuffmanTables[3] = new HuffmanTable();
ScanHeader oScanHeader = new ScanHeader();
oScanHeader.aComponentSelector = new byte[3];
oScanHeader.aHuffmanTablesSelector = new byte[3];
int nMCUBlocksH = 0;
int nMCUBlocksV = 0;
int nRestartInterval = -1;
NppiSize[] aSrcSize = new NppiSize[3];
short[][] aphDCT = new short[3][];
NPPImage_16sC1[] apdDCT = new NPPImage_16sC1[3];
int[] aDCTStep = new int[3];
NPPImage_8uC1[] apSrcImage = new NPPImage_8uC1[3];
int[] aSrcImageStep = new int[3];
NPPImage_8uC1[] apDstImage = new NPPImage_8uC1[3];
int[] aDstImageStep = new int[3];
NppiSize[] aDstSize = new NppiSize[3];
//Same read routine as in NPP JPEG sample from Nvidia
while (nMarker != -1)
{
if (nMarker == 0x0D8)
{
// Embeded Thumbnail, skip it
int nNextMarker = nextMarker(pJpegData, ref nPos, nInputLength);
while (nNextMarker != -1 && nNextMarker != 0x0D9)
{
nNextMarker = nextMarker(pJpegData, ref nPos, nInputLength);
}
}
if (nMarker == 0x0DD)
{
readRestartInterval(pJpegData, ref nPos, ref nRestartInterval);
}
if ((nMarker == 0x0C0) | (nMarker == 0x0C2))
{
//Assert Baseline for this Sample
//Note: NPP does support progressive jpegs for both encode and decode
if (nMarker != 0x0C0)
{
pdQuantizationTables[0].Dispose();
pdQuantizationTables[1].Dispose();
pdQuantizationTables[2].Dispose();
pdQuantizationTables[3].Dispose();
throw new ArgumentException(aFilename + " is not a Baseline-JPEG file.");
}
// Baseline or Progressive Frame Header
readFrameHeader(pJpegData, ref nPos, ref oFrameHeader);
//Console.WriteLine("Image Size: " + oFrameHeader.nWidth + "x" + oFrameHeader.nHeight + "x" + (int)(oFrameHeader.nComponents));
//Assert 3-Channel Image for this Sample
if (oFrameHeader.nComponents != 3)
{
pdQuantizationTables[0].Dispose();
pdQuantizationTables[1].Dispose();
pdQuantizationTables[2].Dispose();
pdQuantizationTables[3].Dispose();
throw new ArgumentException(aFilename + " is not a three channel JPEG file.");
}
// Compute channel sizes as stored in the JPEG (8x8 blocks & MCU block layout)
for (int i = 0; i < oFrameHeader.nComponents; ++i)
{
nMCUBlocksV = Math.Max(nMCUBlocksV, oFrameHeader.aSamplingFactors[i] >> 4);
nMCUBlocksH = Math.Max(nMCUBlocksH, oFrameHeader.aSamplingFactors[i] & 0x0f);
}
for (int i = 0; i < oFrameHeader.nComponents; ++i)
{
NppiSize oBlocks = new NppiSize();
NppiSize oBlocksPerMCU = new NppiSize(oFrameHeader.aSamplingFactors[i] & 0x0f, oFrameHeader.aSamplingFactors[i] >> 4);
oBlocks.width = (int)Math.Ceiling((oFrameHeader.nWidth + 7) / 8 *
(float)(oBlocksPerMCU.width) / nMCUBlocksH);
oBlocks.width = DivUp(oBlocks.width, oBlocksPerMCU.width) * oBlocksPerMCU.width;
oBlocks.height = (int)Math.Ceiling((oFrameHeader.nHeight + 7) / 8 *
(float)(oBlocksPerMCU.height) / nMCUBlocksV);
oBlocks.height = DivUp(oBlocks.height, oBlocksPerMCU.height) * oBlocksPerMCU.height;
aSrcSize[i].width = oBlocks.width * 8;
aSrcSize[i].height = oBlocks.height * 8;
// Allocate Memory
apdDCT[i] = new NPPImage_16sC1(oBlocks.width * 64, oBlocks.height);
aDCTStep[i] = apdDCT[i].Pitch;
apSrcImage[i] = new NPPImage_8uC1(aSrcSize[i].width, aSrcSize[i].height);
aSrcImageStep[i] = apSrcImage[i].Pitch;
aphDCT[i] = new short[aDCTStep[i] * oBlocks.height];
}
}
if (nMarker == 0x0DB)
{
// Quantization Tables
readQuantizationTables(pJpegData, ref nPos, aQuantizationTables);
}
if (nMarker == 0x0C4)
{
// Huffman Tables
readHuffmanTables(pJpegData, ref nPos, aHuffmanTables);
}
if (nMarker == 0x0DA)
{
// Scan
readScanHeader(pJpegData, ref nPos, ref oScanHeader);
nPos += 6 + oScanHeader.nComponents * 2;
int nAfterNextMarkerPos = nPos;
int nAfterScanMarker = nextMarker(pJpegData, ref nAfterNextMarkerPos, nInputLength);
if (nRestartInterval > 0)
{
while (nAfterScanMarker >= 0x0D0 && nAfterScanMarker <= 0x0D7)
{
// This is a restart marker, go on
nAfterScanMarker = nextMarker(pJpegData, ref nAfterNextMarkerPos, nInputLength);
}
}
NppiDecodeHuffmanSpec[] apHuffmanDCTableDec = new NppiDecodeHuffmanSpec[3];
NppiDecodeHuffmanSpec[] apHuffmanACTableDec = new NppiDecodeHuffmanSpec[3];
for (int i = 0; i < 3; ++i)
{
apHuffmanDCTableDec[i] = JPEGCompression.DecodeHuffmanSpecInitAllocHost(aHuffmanTables[(oScanHeader.aHuffmanTablesSelector[i] >> 4)].aCodes, NppiHuffmanTableType.nppiDCTable);
apHuffmanACTableDec[i] = JPEGCompression.DecodeHuffmanSpecInitAllocHost(aHuffmanTables[(oScanHeader.aHuffmanTablesSelector[i] & 0x0f) + 2].aCodes, NppiHuffmanTableType.nppiACTable);
}
byte[] img = new byte[nAfterNextMarkerPos - nPos - 2];
Buffer.BlockCopy(pJpegData, nPos, img, 0, nAfterNextMarkerPos - nPos - 2);
JPEGCompression.DecodeHuffmanScanHost(img, nRestartInterval, oScanHeader.nSs, oScanHeader.nSe, oScanHeader.nA >> 4, oScanHeader.nA & 0x0f, aphDCT[0], aphDCT[1], aphDCT[2], aDCTStep, apHuffmanDCTableDec, apHuffmanACTableDec, aSrcSize);
for (int i = 0; i < 3; ++i)
{
JPEGCompression.DecodeHuffmanSpecFreeHost(apHuffmanDCTableDec[i]);
JPEGCompression.DecodeHuffmanSpecFreeHost(apHuffmanACTableDec[i]);
}
}
nMarker = nextMarker(pJpegData, ref nPos, nInputLength);
}
// Copy DCT coefficients and Quantization Tables from host to device
for (int i = 0; i < 4; ++i)
{
pdQuantizationTables[i].CopyToDevice(aQuantizationTables[i].aTable);
}
for (int i = 0; i < 3; ++i)
{
apdDCT[i].CopyToDevice(aphDCT[i], aDCTStep[i]);
}
// Inverse DCT
for (int i = 0; i < 3; ++i)
{
compression.DCTQuantInv8x8LS(apdDCT[i], apSrcImage[i], aSrcSize[i], pdQuantizationTables[oFrameHeader.aQuantizationTableSelector[i]]);
}
//Alloc final image
NPPImage_8uC3 res = new NPPImage_8uC3(apSrcImage[0].Width, apSrcImage[0].Height);
//Copy Y color plane to first channel
apSrcImage[0].Copy(res, 0);
//Cb anc Cr channel might be smaller
if ((oFrameHeader.aSamplingFactors[0] & 0x0f) == 1 && oFrameHeader.aSamplingFactors[0] >> 4 == 1)
{
//Color planes are of same size as Y channel
apSrcImage[1].Copy(res, 1);
apSrcImage[2].Copy(res, 2);
}
else
{
//rescale color planes to full size
double scaleX = oFrameHeader.aSamplingFactors[0] & 0x0f;
double scaleY = oFrameHeader.aSamplingFactors[0] >> 4;
apSrcImage[1].ResizeSqrPixel(apSrcImage[0], scaleX, scaleY, 0, 0, InterpolationMode.Lanczos);
apSrcImage[0].Copy(res, 1);
apSrcImage[2].ResizeSqrPixel(apSrcImage[0], scaleX, scaleY, 0, 0, InterpolationMode.Lanczos);
apSrcImage[0].Copy(res, 2);
}
//System.Drawing.Bitmap is ordered BGR not RGB
//The NPP routine YCbCR to BGR needs clampled input values, following the YCbCr standard.
//But JPEG uses unclamped values ranging all from [0..255], thus use our own color matrix:
float[,] YCbCrToBgr = new float[3, 4]
{
{ 1.0f, 1.772f, 0.0f, -226.816f },
{ 1.0f, -0.34414f, -0.71414f, 135.45984f },
{ 1.0f, 0.0f, 1.402f, -179.456f }
};
//Convert from YCbCr to BGR
res.ColorTwist(YCbCrToBgr);
Bitmap bmp = new Bitmap(apSrcImage[0].Width, apSrcImage[0].Height, System.Drawing.Imaging.PixelFormat.Format24bppRgb);
res.CopyToHost(bmp);
//Cleanup:
res.Dispose();
apSrcImage[2].Dispose();
apSrcImage[1].Dispose();
apSrcImage[0].Dispose();
apdDCT[2].Dispose();
apdDCT[1].Dispose();
apdDCT[0].Dispose();
pdQuantizationTables[0].Dispose();
pdQuantizationTables[1].Dispose();
pdQuantizationTables[2].Dispose();
pdQuantizationTables[3].Dispose();
compression.Dispose();
return(bmp);
}
