/// <summary>
/// Decompress a JPEG image to an RGB, grayscale, or CMYK image into precreated unmanaged buffer
/// </summary>
/// <param name="jpegBuf">Pointer to a buffer containing the JPEG image to decompress. This buffer is not modified</param>
/// <param name="jpegBufSize">Size of the JPEG image (in bytes)</param>
/// <param name="outBuf">Pointer to output buffer where decompressed image will be put. Buffer must be created before call</param>
/// <param name="outBufSize">Size of output buffer (in bytes). It must be greater or equal than size of decompressed image</param>
/// <param name="destPixelFormat">Pixel format of the destination image (see <see cref="TJPixelFormats"/> "Pixel formats".)</param>
/// <param name="flags">The bitwise OR of one or more of the <see cref="TJFlags"/> "flags"</param>
/// <exception cref="TJException">Throws if underlying decompress function failed</exception>
/// <exception cref="ObjectDisposedException">Object is disposed and can not be used anymore</exception>
// ReSharper disable once ParameterOnlyUsedForPreconditionCheck.Global
public void Decompress(IntPtr jpegBuf, ulong jpegBufSize, IntPtr outBuf, int outBufSize, TJPixelFormats destPixelFormat, TJFlags flags)
{
GetImageInfo(jpegBuf, jpegBufSize, destPixelFormat, out var width, out var height, out var stride, out var bufSize);
if (outBufSize < bufSize)
{
throw new ArgumentOutOfRangeException("outBufSize");
}
var funcResult = TurboJpegImport.tjDecompress(
_decompressorHandle,
jpegBuf,
jpegBufSize,
outBuf,
width,
stride,
height,
(int)destPixelFormat,
(int)flags);
if (funcResult == -1)
{
TJUtils.GetErrorAndThrow();
}
}
public unsafe void Decompress(IntPtr jpegBuf, ulong jpegBufSize, IntPtr outBuf, int outBufSize, TJPixelFormats destPixelFormat, TJFlags flags, out int width, out int height, out int stride)
{
if (_isDisposed)
{
throw new ObjectDisposedException("this");
}
int subsampl;
int colorspace;
var funcResult = TurboJpegImport.tjDecompressHeader(_decompressorHandle, jpegBuf, jpegBufSize,
out width, out height, out subsampl, out colorspace);
if (funcResult == -1)
{
TJUtils.GetErrorAndThrow();
}
var targetFormat = destPixelFormat;
stride = TurboJpegImport.TJPAD(width * TurboJpegImport.PixelSizes[targetFormat]);
var bufSize = stride * height;
if (outBufSize < bufSize)
{
throw new ArgumentOutOfRangeException(nameof(outBufSize));
}
funcResult = TurboJpegImport.tjDecompress(
_decompressorHandle,
jpegBuf,
jpegBufSize,
outBuf,
width,
stride,
height,
(int)targetFormat,
(int)flags);
if (funcResult == -1)
{
TJUtils.GetErrorAndThrow();
}
}
/// <summary>
/// Decompress a JPEG image to an RGB, grayscale, or CMYK image.
/// </summary>
/// <param name="jpegBuf">Pointer to a buffer containing the JPEG image to decompress. This buffer is not modified</param>
/// <param name="jpegBufSize">Size of the JPEG image (in bytes)</param>
/// <param name="destPixelFormat">Pixel format of the destination image</param>
/// <param name="flags">The bitwise OR of one or more of the <see cref="TJFlags"/> "flags"</param>
/// <param name="width">Width of image in pixels</param>
/// <param name="height">Height of image in pixels</param>
/// <param name="stride">Bytes per line in the destination image</param>
/// <returns>Raw pixel data of specified format</returns>
/// <exception cref="TJException">Throws if underlying decompress function failed</exception>
/// <exception cref="ObjectDisposedException">Object is disposed and can not be used anymore</exception>
public unsafe byte[] Decompress(IntPtr jpegBuf, ulong jpegBufSize, TJPixelFormats destPixelFormat, TJFlags flags, out int width, out int height, out int stride)
{
if (_isDisposed)
{
throw new ObjectDisposedException("this");
}
var funcResult = TurboJpegImport.tjDecompressHeader(_decompressorHandle, jpegBuf, jpegBufSize,
out width, out height, out _, out _);
if (funcResult == -1)
{
TJUtils.GetErrorAndThrow();
}
var targetFormat = destPixelFormat;
stride = TurboJpegImport.TJPAD(width * TurboJpegImport.PixelSizes[targetFormat]);
var bufSize = stride * height;
var buf = new byte[bufSize];
fixed(byte *bufPtr = buf)
{
funcResult = TurboJpegImport.tjDecompress(
_decompressorHandle,
jpegBuf,
jpegBufSize,
(IntPtr)bufPtr,
width,
stride,
height,
(int)targetFormat,
(int)flags);
if (funcResult == -1)
{
TJUtils.GetErrorAndThrow();
}
return(buf);
}
}
