/// <summary>
/// Retrieve information about a JPEG image without decompressing it.
/// </summary>
/// <param name="jpegBuf">
/// Pointer to a buffer containing a JPEG image. This buffer is not modified.
/// </param>
/// <param name="jpegBufSize">
/// Size of the JPEG image (in bytes)
/// </param>
/// <param name="destPixelFormat">
/// The pixel format of the uncompressed image.
/// </param>
/// <param name="width">
/// Pointer to an integer variable that will receive the width (in pixels) of the JPEG image
/// </param>
/// <param name="height">
/// Pointer to an integer variable that will receive the height (in pixels) of the JPEG image
/// </param>
/// <param name="stride">
/// Pointer to an integer variable that will receive the stride (in bytes) of the JPEG image.
/// </param>
/// <param name="bufSize">
/// The size of a buffer that can receive the uncompressed JPEG image.
/// </param>
public void GetImageInfo(IntPtr jpegBuf, ulong jpegBufSize, TJPixelFormats destPixelFormat, out int width, out int height, out int stride, out int bufSize)
{
int subsampl;
int colorspace;
var funcResult = TurboJpegImport.tjDecompressHeader(_decompressorHandle, jpegBuf, jpegBufSize,
out width, out height, out subsampl, out colorspace);
stride = TurboJpegImport.TJPAD(width * TurboJpegImport.PixelSizes[destPixelFormat]);
bufSize = stride * height;
}
/// <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="outBuf">The buffer into which to store the decompressed JPEG image.</param>
/// <param name="outBufSize">Size of <paramref name="outBuf"/> (in bytes).</param>
/// <param name="destPixelFormat">Pixel format of the destination image (see <see cref="PixelFormat"/> "Pixel formats".)</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>
public unsafe void Decompress(IntPtr jpegBuf, ulong jpegBufSize, IntPtr outBuf, int outBufSize, TJPixelFormat destPixelFormat, TJFlags flags, out int width, out int height, out int stride)
{
if (this.isDisposed)
{
throw new ObjectDisposedException("this");
}
int subsampl;
int colorspace;
var funcResult = TurboJpegImport.TjDecompressHeader(
this.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(
this.decompressorHandle,
jpegBuf,
jpegBufSize,
outBuf,
width,
stride,
height,
(int)targetFormat,
(int)flags);
if (funcResult == -1)
{
TJUtils.GetErrorAndThrow();
}
}
/// <summary>
/// Returns info about jpeg image without decompressing it
/// </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="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>
/// <param name="decompressedBufferSize">Size in bytes for buffer where decompressed image will be put</param>
/// <exception cref="TJException">Throws if underlying decompress function failed</exception>
/// <exception cref="ObjectDisposedException">Object is disposed and can not be used anymore</exception>
/// <returns></returns>
public void GetImageInfo(IntPtr jpegBuf, ulong jpegBufSize, TJPixelFormats destPixelFormat, out int width, out int height, out int stride, out int decompressedBufferSize)
{
if (_isDisposed)
{
throw new ObjectDisposedException("this");
}
var funcResult = TurboJpegImport.tjDecompressHeader(_decompressorHandle, jpegBuf, jpegBufSize,
out width, out height, out _, out _);
if (funcResult == -1)
{
TJUtils.GetErrorAndThrow();
}
stride = TurboJpegImport.TJPAD(width * TurboJpegImport.PixelSizes[destPixelFormat]);
decompressedBufferSize = stride * height;
}
/// <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);
}
}
/// <summary>
/// Given the size of an image, determines the size of a decompressed image.
/// </summary>
/// <param name="height">
/// The height of the image.
/// </param>
/// <param name="width">
/// The width of the image.
/// </param>
/// <param name="destPixelFormat">
/// The pixel format of the uncompressed image.
/// </param>
/// <returns>
/// The size of a buffer that can hold the uncompressed image.
/// </returns>
public int GetBufferSize(int height, int width, TJPixelFormats destPixelFormat)
{
int stride = TurboJpegImport.TJPAD(width * TurboJpegImport.PixelSizes[destPixelFormat]);
return(stride * height);
}
