public void KernelTest1()
{
double[,] expected =
{
{ 2.1693514414478006E-34, 2.4546349229561677E-22, -1.5279500064746295E-21 },
{ -0.00000069069240704724283, 0.9210609940028851, -0.00000012799017494227224 },
{ -7.7578659683414284E-22, -4.1079449607342235E-22, 3.2663608516186217E-34 }
};
double[,] actual = Gabor.Kernel2D(sigma: 0.1, theta: 0.2, lambda: 0.3, psi: 0.4, gamma: 0.5);
Assert.AreEqual(actual.GetLength(0), expected.GetLength(0));
Assert.AreEqual(actual.GetLength(1), expected.GetLength(1));
for (int i = 0; i < actual.GetLength(0); i++)
{
for (int j = 0; j < actual.GetLength(1); j++)
{
double e = expected[i, j];
double a = actual[i, j];
Assert.AreEqual(e, a, System.Math.Abs(e * 1e-10));
}
}
}
public void KernelTest2()
{
double[,] expected =
{
{ 1.42405394857622E-52, -1.55301965707389E-39, -5.91718738982049E-28, 6.74066784260594E-19, 9.45212732580885E-13, -1.54728187127383E-07, 1.35216035740648E-05 },
{ 2.44396261647309E-27, 6.22350869845861E-18, -2.53179283832159E-10, 4.71970195306204E-06, 0.01750857512698, -0.0562293027375883, -0.000676655483164679 },
{ -1.18923149745881E-11, 3.26086352470611E-05, -0.0380349460494781, -0.653643620863612, 0.0705347070196069, 1.49826805190377E-06, -8.02838283000017E-11 },
{ -0.00143882468734695, 0.0594224852404454, 0.00675479754684435, -2.97718145336781E-05, 8.09821092370491E-11, 1.01520928946922E-17, -3.06243455885214E-27 },
{ -2.89102012691001E-05, 2.93060843736615E-09, 4.32869511491687E-12, -4.97862860483868E-19, -4.04134720949385E-28, 4.26508052356691E-39, -1.65106988580208E-53 }
};
double[,] actual = Gabor.Kernel2D(sigma: 1, theta: 2, lambda: 3, psi: 4, gamma: 5);
Assert.AreEqual(actual.GetLength(0), expected.GetLength(0));
Assert.AreEqual(actual.GetLength(1), expected.GetLength(1));
for (int i = 0; i < actual.GetLength(0); i++)
{
for (int j = 0; j < actual.GetLength(1); j++)
{
double e = expected[i, j];
double a = actual[i, j];
Assert.AreEqual(e, a, System.Math.Abs(e * 1e-10));
}
}
}
/// <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)
{
// check image format
if ((sourceData.PixelFormat != PixelFormat.Format8bppIndexed) &&
(sourceData.PixelFormat != PixelFormat.Format24bppRgb))
{
throw new UnsupportedImageFormatException("Unsupported image format.");
}
if (sourceData.PixelFormat != PixelFormat.Format8bppIndexed)
{
sourceData = Grayscale.CommonAlgorithms.BT709.Apply(sourceData);
}
if (recompute)
{
recompute = false;
kernel = Gabor.Kernel2D(size: size,
lambda: lambda,
theta: theta,
psi: psi,
sigma: sigma,
gamma: gamma,
normalized: true,
function: GaborKernelKind.Imaginary);
}
int kernelHeight = kernel.GetLength(0);
int kernelWidth = kernel.GetLength(1);
int centerX = kernelHeight / 2;
int centerY = kernelWidth / 2;
int width = sourceData.Width;
int height = sourceData.Height;
int srcStride = sourceData.Stride;
int srcOffset = srcStride - width;
byte *src = (byte *)sourceData.ImageData.ToPointer();
int[,] response = new int[height, width];
int max = int.MinValue;
int min = int.MaxValue;
// for each image row
for (int y = 0; y < height; y++)
{
// for each pixel in the row
for (int x = 0; x < width; x++, src++)
{
double sum = 0;
// for each kernel row
for (int i = 0; i < kernelHeight; i++)
{
int ir = i - centerY;
int t = y + ir;
// skip row
if (t < 0)
{
continue;
}
// break
if (t >= height)
{
break;
}
int col = ir * srcStride;
// for each kernel value in the row
for (int j = 0; j < kernelWidth; j++)
{
int jr = j - centerX;
t = x + jr;
// skip column
if (t < 0)
{
continue;
}
if (t < width)
{
double k = kernel[i, j];
sum += k * src[col + jr];
}
}
int v = response[y, x] = (int)sum;
if (v > max)
{
max = v;
}
if (v < min)
{
min = v;
}
}
}
src += srcOffset;
}
byte *dst = (byte *)destinationData.ImageData.ToPointer();
int pixelSize = System.Drawing.Image.GetPixelFormatSize(destinationData.PixelFormat) / 8;
int dstStride = destinationData.Stride;
int dstOffset = dstStride - width * pixelSize;
if (destinationData.PixelFormat == PixelFormat.Format8bppIndexed)
{
// for each image row
for (int y = 0; y < height; y++)
{
// for each pixel in the row
for (int x = 0; x < width; x++, dst++)
{
*dst = (byte)((255 * (response[y, x] - min)) / (max - min));
}
dst += dstOffset;
}
}
else
{
// for each image row
for (int y = 0; y < height; y++)
{
// for each pixel in the row
for (int x = 0; x < width; x++, dst += pixelSize)
{
int v = response[y, x];
if (v > 0)
{
dst[RGB.R] = (byte)((255 * v) / max);
}
else // (v <= 0)
{
dst[RGB.B] = (byte)((255 * v) / min);
}
}
dst += dstOffset;
}
}
}