public FloatImage Convolve(FloatImage k)
{
var kw = k.Width;
var kh = k.Height;
var kxs = kw >> 1;
var kys = kh >> 1;
var r = new FloatImage(_Width, _Height);
float total = k.Sum();
for (var dy = 0; dy < _Height; dy++)
{
for (var dx = 0; dx < _Width; dx++)
{
var v = 0f;
var sum = 0f;
for (var ky = 0; ky < kh; ky++)
{
var sy = dy + ky - kys;
if (sy < 0 || _Height <= sy)
{
continue;
}
for (var kx = 0; kx < kh; kx++)
{
var sx = dx + kx - kxs;
if (sx < 0 || _Width <= sx)
{
continue;
}
var sv = this[sx, sy];
var kv = k[kx, ky];
v += sv * kv;
sum += kv;
}
}
r[dx, dy] = total == sum ? v : (v * total / sum);
}
}
return(r);
}
internal static FloatImage ConvolveSingle(T image, FloatImage kernel, int kernelWidth, int kernelHeight)
{
var kernelXRadius = kernel.Width >> 1;
var kernelYRadius = kernelHeight >> 1;
var r = new FloatImage(image.Width, image.Height);
float total = kernel.Sum();
for (var dy = 0; dy < image.Height; dy++)
{
for (var dx = 0; dx < image.Width; dx++)
{
var v = 0f;
var sum = 0f;
for (var ky = 0; ky < kernelHeight; ky++)
{
var sy = dy + ky - kernelYRadius;
if (sy < 0 || image.Height <= sy)
{
continue;
}
for (var kx = 0; kx < kernelWidth; kx++)
{
var sx = dx + kx - kernelXRadius;
if (sx < 0 || image.Width <= sx)
{
continue;
}
var sv = image[sx, sy];
var kv = kernel[kx, ky];
v += sv * kv;
sum += kv;
}
}
r[dx, dy] = total == sum ? v : (v * total / sum);
}
}
return(r);
}