/// <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)
{
int width = sourceData.Width;
int height = sourceData.Height;
int pixelSize = System.Drawing.Image.GetPixelFormatSize(sourceData.PixelFormat) / 8;
int srcStride = sourceData.Stride;
int dstStride = destinationData.Stride;
int srcOffset = srcStride - width * pixelSize;
int dstOffset = dstStride - width * pixelSize;
byte *src = (byte *)sourceData.ImageData.ToPointer();
byte *dst = (byte *)destinationData.ImageData.ToPointer();
// TODO: Move or cache the creation of those filters
int[,] kernel = BestCS.Math.Matrix.Create(radius * 2 + 1, radius * 2 + 1, 1);
Convolution conv = new Convolution(kernel);
FastVariance fv = new FastVariance(radius);
// Mean filter
UnmanagedImage mean = conv.Apply(sourceData);
// Variance filter
UnmanagedImage var = fv.Apply(sourceData);
// do the processing job
if (sourceData.PixelFormat == PixelFormat.Format8bppIndexed)
{
byte *srcVar = (byte *)var.ImageData.ToPointer();
byte *srcMean = (byte *)mean.ImageData.ToPointer();
// Store maximum value from variance.
int maxV = Max(width, height, srcVar, srcOffset);
// Store minimum value from image.
int minG = Min(width, height, src, srcOffset);
for (int y = 0; y < height; y++)
{
for (int x = 0; x < width; x++, src++, srcMean++, srcVar++, dst++)
{
double mP = *srcMean;
double vP = *srcVar;
double threshold = (mP + k * ((Math.Sqrt(vP) / (double)maxV - 1.0) * (mP - (double)minG)));
*dst = (byte)(*src > threshold ? 255 : 0);
}
src += srcOffset;
srcMean += srcOffset;
srcVar += srcOffset;
dst += dstOffset;
}
}
}
/// <summary>
/// Process the filter on the specified image.
/// </summary>
///
/// <param name="sourceData">Source image data.</param>
/// <param name="destinationData">Destination image data.</param>
///
protected unsafe override void ProcessFilter(UnmanagedImage sourceData, UnmanagedImage destinationData)
{
int width = sourceData.Width;
int height = sourceData.Height;
PixelFormat format = sourceData.PixelFormat;
int pixelSize = System.Drawing.Bitmap.GetPixelFormatSize(format) / 8;
sourceData.Clone();
UnmanagedImage temp = UnmanagedImage.Create(width, height, format);
int lineWidth = width * pixelSize;
int srcStride = temp.Stride;
int srcOffset = srcStride - lineWidth;
int dstStride = destinationData.Stride;
int dstOffset = dstStride - lineWidth;
byte *srcStart = (byte *)temp.ImageData.ToPointer();
byte *dstStart = (byte *)destinationData.ImageData.ToPointer();
// first
Convolution c = new Convolution(masks[0]);
c.Apply(sourceData, destinationData);
// others
for (int i = 1; i < masks.Length; i++)
{
c.Kernel = masks[i];
c.Apply(sourceData, temp);
byte *src = srcStart;
byte *dst = dstStart;
for (int y = 0; y < height; y++)
{
for (int x = 0; x < lineWidth; x++, src++, dst++)
{
if (*src > *dst)
{
*dst = *src;
}
}
dst += dstOffset;
src += srcOffset;
}
}
}
