/// <summary>
/// Create unmanaged image from the specified managed image.
/// </summary>
///
/// <param name="imageData">Source locked image data.</param>
///
/// <returns>Returns new unmanaged image, which is a copy of source managed image.</returns>
///
/// <remarks><para>The method creates an exact copy of specified managed image, but allocated
/// in unmanaged memory. This means that managed image may be unlocked right after call to this
/// method.</para></remarks>
///
/// <exception cref="UnsupportedImageFormatException">Unsupported pixel format of source image.</exception>
///
public static UnmanagedImage FromManagedImage(BitmapData imageData)
{
PixelFormat pixelFormat = imageData.PixelFormat;
// check source pixel format
if (
(pixelFormat != PixelFormat.Format8bppIndexed) &&
(pixelFormat != PixelFormat.Format16bppGrayScale) &&
(pixelFormat != PixelFormat.Format24bppRgb) &&
(pixelFormat != PixelFormat.Format32bppRgb) &&
(pixelFormat != PixelFormat.Format32bppArgb) &&
(pixelFormat != PixelFormat.Format32bppPArgb) &&
(pixelFormat != PixelFormat.Format48bppRgb) &&
(pixelFormat != PixelFormat.Format64bppArgb) &&
(pixelFormat != PixelFormat.Format64bppPArgb))
{
throw new Exception("Unsupported pixel format of the source image.");
}
// allocate memory for the image
IntPtr dstImageData = System.Runtime.InteropServices.Marshal.AllocHGlobal(imageData.Stride * imageData.Height);
System.GC.AddMemoryPressure(imageData.Stride * imageData.Height);
UnmanagedImage image = new UnmanagedImage(dstImageData, imageData.Width, imageData.Height, imageData.Stride, pixelFormat);
SystemTools.CopyUnmanagedMemory(dstImageData, imageData.Scan0, imageData.Stride * imageData.Height);
image.mustBeDisposed = true;
return(image);
}
/// <summary>
/// Copy unmanaged image.
/// </summary>
///
/// <param name="destImage">Destination image to copy this image to.</param>
///
/// <remarks><para>The method copies current unmanaged image to the specified image.
/// Size and pixel format of the destination image must be exactly the same.</para></remarks>
///
/// <exception cref="InvalidImagePropertiesException">Destination image has different size or pixel format.</exception>
///
public void Copy(UnmanagedImage destImage)
{
if (
(width != destImage.width) || (height != destImage.height) ||
(pixelFormat != destImage.pixelFormat))
{
throw new Exception("Destination image has different size or pixel format.");
}
if (stride == destImage.stride)
{
// copy entire image
SystemTools.CopyUnmanagedMemory(destImage.imageData, imageData, stride * height);
}
else
{
unsafe
{
int dstStride = destImage.stride;
int copyLength = (stride < dstStride) ? stride : dstStride;
byte *src = (byte *)imageData.ToPointer();
byte *dst = (byte *)destImage.imageData.ToPointer();
// copy line by line
for (int i = 0; i < height; i++)
{
SystemTools.CopyUnmanagedMemory(dst, src, copyLength);
dst += dstStride;
src += stride;
}
}
}
}
/// <summary>
/// Clone the unmanaged images.
/// </summary>
///
/// <returns>Returns clone of the unmanaged image.</returns>
///
/// <remarks><para>The method does complete cloning of the object.</para></remarks>
///
public UnmanagedImage Clone()
{
// allocate memory for the image
IntPtr newImageData = System.Runtime.InteropServices.Marshal.AllocHGlobal(stride * height);
System.GC.AddMemoryPressure(stride * height);
UnmanagedImage newImage = new UnmanagedImage(newImageData, width, height, stride, pixelFormat);
newImage.mustBeDisposed = true;
SystemTools.CopyUnmanagedMemory(newImageData, imageData, stride * height);
return(newImage);
}
public static Bitmap Clone(BitmapData sourceData)
{
// get source image size
int width = sourceData.Width;
int height = sourceData.Height;
// create new image
Bitmap destination = new Bitmap(width, height, sourceData.PixelFormat);
// lock destination bitmap data
BitmapData destinationData = destination.LockBits(
new Rectangle(0, 0, width, height),
ImageLockMode.ReadWrite, destination.PixelFormat);
SystemTools.CopyUnmanagedMemory(destinationData.Scan0, sourceData.Scan0, height * sourceData.Stride);
// unlock destination image
destination.UnlockBits(destinationData);
return(destination);
}
/// <summary>
/// Process the filter on the specified image.
/// </summary>
///
/// <param name="sourceData">Source image data.</param>
/// <param name="destinationData">Destination image data.</param>
///
protected override unsafe void ProcessFilter(UnmanagedImage sourceData, UnmanagedImage destinationData)
{
// validate rectangle
Rectangle srcRect = rect;
srcRect.Intersect(new Rectangle(0, 0, sourceData.Width, sourceData.Height));
int xmin = srcRect.Left;
int ymin = srcRect.Top;
int ymax = srcRect.Bottom - 1;
int copyWidth = srcRect.Width;
int srcStride = sourceData.Stride;
int dstStride = destinationData.Stride;
int pixelSize = Image.GetPixelFormatSize(sourceData.PixelFormat) / 8;
int copySize = copyWidth * pixelSize;
// do the job
byte *src = (byte *)sourceData.ImageData.ToPointer() + ymin * srcStride + xmin * pixelSize;
byte *dst = (byte *)destinationData.ImageData.ToPointer();
if (rect.Top < 0)
{
dst -= dstStride * rect.Top;
}
if (rect.Left < 0)
{
dst -= pixelSize * rect.Left;
}
// for each line
for (int y = ymin; y <= ymax; y++)
{
SystemTools.CopyUnmanagedMemory(dst, src, copySize);
src += srcStride;
dst += dstStride;
}
}
/// <summary>
/// Create managed image from the unmanaged.
/// </summary>
///
/// <param name="makeCopy">Make a copy of the unmanaged image or not.</param>
///
/// <returns>Returns managed copy of the unmanaged image.</returns>
///
/// <remarks><para>If the <paramref name="makeCopy"/> is set to <see langword="true"/>, then the method
/// creates a managed copy of the unmanaged image, so the managed image stays valid even when the unmanaged
/// image gets disposed. However, setting this parameter to <see langword="false"/> creates a managed image which is
/// just a wrapper around the unmanaged image. So if unmanaged image is disposed, the
/// managed image becomes no longer valid and accessing it will generate an exception.</para></remarks>
///
/// <exception cref="InvalidImagePropertiesException">The unmanaged image has some invalid properties, which results
/// in failure of converting it to managed image. This may happen if user used the
/// <see cref="UnmanagedImage(IntPtr, int, int, int, PixelFormat)"/> constructor specifying some
/// invalid parameters.</exception>
///
public Bitmap ToManagedImage(bool makeCopy)
{
Bitmap dstImage = null;
try
{
if (!makeCopy)
{
dstImage = new Bitmap(width, height, stride, pixelFormat, imageData);
if (pixelFormat == PixelFormat.Format8bppIndexed)
{
ImageHelper.SetGrayscalePalette(dstImage);
}
}
else
{
// create new image of required format
dstImage = (pixelFormat == PixelFormat.Format8bppIndexed) ?
ImageHelper.CreateGrayscaleImage(width, height) :
new Bitmap(width, height, pixelFormat);
// lock destination bitmap data
BitmapData dstData = dstImage.LockBits(
new Rectangle(0, 0, width, height),
ImageLockMode.ReadWrite, pixelFormat);
int dstStride = dstData.Stride;
int lineSize = Math.Min(stride, dstStride);
unsafe
{
byte *dst = (byte *)dstData.Scan0.ToPointer();
byte *src = (byte *)imageData.ToPointer();
if (stride != dstStride)
{
// copy image
for (int y = 0; y < height; y++)
{
SystemTools.CopyUnmanagedMemory(dst, src, lineSize);
dst += dstStride;
src += stride;
}
}
else
{
SystemTools.CopyUnmanagedMemory(dst, src, stride * height);
}
}
// unlock destination images
dstImage.UnlockBits(dstData);
}
return(dstImage);
}
catch (Exception)
{
if (dstImage != null)
{
dstImage.Dispose();
}
throw new Exception("The unmanaged image has some invalid properties, which results in failure of converting it to managed image.");
}
}