public static Bitmap EdgeDetectQuick(Bitmap b)
{
ConvMatrix m = new ConvMatrix();
m.TopLeft = m.TopMid = m.TopRight = -1;
m.MidLeft = m.Pixel = m.MidRight = 0;
m.BottomLeft = m.BottomMid = m.BottomRight = 1;
m.Offset = 127;
return(BitmapFilter.Conv3x3(b, m));
}
public static Bitmap EdgeDetectConvolution(Bitmap b, EdgeDetectionMethod nType, byte nThreshold)
{
ConvMatrix m = new ConvMatrix();
// First we need to keep a copy of the original Bitmap.
using (Bitmap bTemp = (Bitmap)b.Clone())
{
try
{
switch (nType)
{
case EdgeDetectionMethod.Sobel:
m.SetAll(0);
m.TopLeft = m.BottomLeft = 1;
m.TopRight = m.BottomRight = -1;
m.MidLeft = 2;
m.MidRight = -2;
m.Offset = 0;
break;
case EdgeDetectionMethod.Prewitt:
m.SetAll(0);
m.TopLeft = m.MidLeft = m.BottomLeft = -1;
m.TopRight = m.MidRight = m.BottomRight = 1;
m.Offset = 0;
break;
case EdgeDetectionMethod.Kirsh:
m.SetAll(-3);
m.Pixel = 0;
m.TopLeft = m.MidLeft = m.BottomLeft = 5;
m.Offset = 0;
break;
}
BitmapFilter.Conv3x3(b, m);
switch (nType)
{
case EdgeDetectionMethod.Sobel:
m.SetAll(0);
m.TopLeft = m.TopRight = 1;
m.BottomLeft = m.BottomRight = -1;
m.TopMid = 2;
m.BottomMid = -2;
m.Offset = 0;
break;
case EdgeDetectionMethod.Prewitt:
m.SetAll(0);
m.BottomLeft = m.BottomMid = m.BottomRight = -1;
m.TopLeft = m.TopMid = m.TopRight = 1;
m.Offset = 0;
break;
case EdgeDetectionMethod.Kirsh:
m.SetAll(-3);
m.Pixel = 0;
m.BottomLeft = m.BottomMid = m.BottomRight = 5;
m.Offset = 0;
break;
}
BitmapFilter.Conv3x3(bTemp, m);
}
catch
{ throw; }
// GDI+ lies - return format is BGR, not RGB.
BitmapData bmpData = b.LockBits(new Rectangle(0, 0, b.Width, b.Height), ImageLockMode.ReadWrite, PixelFormat.Format24bppRgb);
BitmapData bmpData2 = bTemp.LockBits(new Rectangle(0, 0, b.Width, b.Height), ImageLockMode.ReadWrite, PixelFormat.Format24bppRgb);
try
{
int stride = bmpData.Stride;
unsafe
{
byte *p = (byte *)(void *)bmpData.Scan0;
byte *p2 = (byte *)(void *)bmpData2.Scan0;
int nOffset = stride - b.Width * 3;
int nWidth = b.Width * 3;
int nPixel = 0;
for (int y = 0; y < b.Height; ++y)
{
for (int x = 0; x < nWidth; ++x)
{
nPixel = (int)System.Math.Sqrt((p[0] * p[0]) + (p2[0] * p2[0]));
if (nPixel < nThreshold)
{
nPixel = nThreshold;
}
if (nPixel > 255)
{
nPixel = 255;
}
p[0] = (byte)nPixel;
++p;
++p2;
}
p += nOffset;
p2 += nOffset;
}
}
}
catch
{ throw; }
finally
{
b.UnlockBits(bmpData);
bTemp.UnlockBits(bmpData2);
}
}
return(b);
}
public static Bitmap Conv3x3(Bitmap b, ConvMatrix m)
{
// Avoid divide by zero errors.
if (m.Factor == 0)
{
throw new ArgumentException("Conversion matrix factor must be greater than zero.", "m");
}
Bitmap bmpDest = new Bitmap(b.Width, b.Height);
// GDI+ lies - the return format is BGR, not RGB (stupid little-endian)
BitmapData bitData = bmpDest.LockBits(new Rectangle(0, 0, bmpDest.Width, bmpDest.Height), ImageLockMode.ReadWrite, PixelFormat.Format24bppRgb);
BitmapData bitSrc = b.LockBits(new Rectangle(0, 0, b.Width, b.Height), ImageLockMode.ReadOnly, PixelFormat.Format24bppRgb);
try
{
int stride = bitSrc.Stride;
int stride2 = bitSrc.Stride * 2;
unsafe
{
for (int y = 0; y < b.Height - 2; y++)
{
byte *ptrSrc = (byte *)bitSrc.Scan0 + y * bitSrc.Stride;
byte *ptrDest = (byte *)bitSrc.Scan0 + y * bitData.Stride;
for (int x = 0; x < b.Width - 2; x++)
{
// Set R channel (remember, bytes are BGR, not RGB, thanks to little endian byte order).
int nPixelR = (((ptrSrc[x * 3 + 2] * m.TopLeft) + (ptrSrc[x * 3 + 5] * m.TopMid) + (ptrSrc[x * 3 + 8] * m.TopRight) +
(ptrSrc[x * 3 + 2 + stride] * m.MidLeft) + (ptrSrc[x * 3 + 5 + stride] * m.Pixel) + (ptrSrc[x * 3 + 8 + stride] * m.MidRight) +
(ptrSrc[x * 3 + 2 + stride2] * m.BottomLeft) + (ptrSrc[x * 3 + 5 + stride2] * m.BottomMid) + (ptrSrc[x * 3 + 8 + stride2] * m.BottomRight)) / m.Factor) + m.Offset;
nPixelR = (int)System.Math.Max(0, System.Math.Min(255, nPixelR));
ptrDest[5 + stride] = (byte)nPixelR;
// Set G channel.
int nPixelG = (((ptrSrc[x * 3 + 1] * m.TopLeft) + (ptrSrc[x * 3 + 4] * m.TopMid) + (ptrSrc[x * 3 + 7] * m.TopRight) +
(ptrSrc[x * 3 + 1 + stride] * m.MidLeft) + (ptrSrc[x * 3 + 4 + stride] * m.Pixel) + (ptrSrc[x * 3 + 7 + stride] * m.MidRight) +
(ptrSrc[x * 3 + 1 + stride2] * m.BottomLeft) + (ptrSrc[x * 3 + 4 + stride2] * m.BottomMid) + (ptrSrc[x * 3 + 7 + stride2] * m.BottomRight)) / m.Factor) + m.Offset;
nPixelG = (int)System.Math.Max(0, System.Math.Min(255, nPixelG));
ptrDest[4 + stride] = (byte)nPixelG;
// Set B channel.
int nPixelB = (((ptrSrc[x * 3 + 0] * m.TopLeft) + (ptrSrc[x * 3 + 3] * m.TopMid) + (ptrSrc[x * 3 + 6] * m.TopRight) +
(ptrSrc[x * 3 + 0 + stride] * m.MidLeft) + (ptrSrc[x * 3 + 3 + stride] * m.Pixel) + (ptrSrc[x * 3 + 6 + stride] * m.MidRight) +
(ptrSrc[x * 3 + 0 + stride2] * m.BottomLeft) + (ptrSrc[x * 3 + 3 + stride2] * m.BottomMid) + (ptrSrc[x * 3 + 6 + stride2] * m.BottomRight)) / m.Factor) + m.Offset;
nPixelB = (int)System.Math.Max(0, System.Math.Min(255, nPixelB));
ptrDest[3 + stride] = (byte)nPixelB;
}
}
}
}
catch
{
if (bmpDest != null)
{
bmpDest.Dispose();
}
throw;
}
finally
{
bmpDest.UnlockBits(bitData);
b.UnlockBits(bitSrc);
}
return(bmpDest);
}
public static Bitmap EdgeDetectQuick(Bitmap b)
{
ConvMatrix m = new ConvMatrix();
m.TopLeft = m.TopMid = m.TopRight = -1;
m.MidLeft = m.Pixel = m.MidRight = 0;
m.BottomLeft = m.BottomMid = m.BottomRight = 1;
m.Offset = 127;
return BitmapFilter.Conv3x3(b, m);
}
public static Bitmap EdgeDetectConvolution(Bitmap b, EdgeDetectionMethod nType, byte nThreshold)
{
ConvMatrix m = new ConvMatrix();
// First we need to keep a copy of the original Bitmap.
using (Bitmap bTemp = (Bitmap)b.Clone())
{
try
{
switch (nType)
{
case EdgeDetectionMethod.Sobel:
m.SetAll(0);
m.TopLeft = m.BottomLeft = 1;
m.TopRight = m.BottomRight = -1;
m.MidLeft = 2;
m.MidRight = -2;
m.Offset = 0;
break;
case EdgeDetectionMethod.Prewitt:
m.SetAll(0);
m.TopLeft = m.MidLeft = m.BottomLeft = -1;
m.TopRight = m.MidRight = m.BottomRight = 1;
m.Offset = 0;
break;
case EdgeDetectionMethod.Kirsh:
m.SetAll(-3);
m.Pixel = 0;
m.TopLeft = m.MidLeft = m.BottomLeft = 5;
m.Offset = 0;
break;
}
BitmapFilter.Conv3x3(b, m);
switch (nType)
{
case EdgeDetectionMethod.Sobel:
m.SetAll(0);
m.TopLeft = m.TopRight = 1;
m.BottomLeft = m.BottomRight = -1;
m.TopMid = 2;
m.BottomMid = -2;
m.Offset = 0;
break;
case EdgeDetectionMethod.Prewitt:
m.SetAll(0);
m.BottomLeft = m.BottomMid = m.BottomRight = -1;
m.TopLeft = m.TopMid = m.TopRight = 1;
m.Offset = 0;
break;
case EdgeDetectionMethod.Kirsh:
m.SetAll(-3);
m.Pixel = 0;
m.BottomLeft = m.BottomMid = m.BottomRight = 5;
m.Offset = 0;
break;
}
BitmapFilter.Conv3x3(bTemp, m);
}
catch
{ throw; }
// GDI+ lies - return format is BGR, not RGB.
BitmapData bmpData = b.LockBits(new Rectangle(0, 0, b.Width, b.Height), ImageLockMode.ReadWrite, PixelFormat.Format24bppRgb);
BitmapData bmpData2 = bTemp.LockBits(new Rectangle(0, 0, b.Width, b.Height), ImageLockMode.ReadWrite, PixelFormat.Format24bppRgb);
try
{
int stride = bmpData.Stride;
unsafe
{
byte* p = (byte*)(void*)bmpData.Scan0;
byte* p2 = (byte*)(void*)bmpData2.Scan0;
int nOffset = stride - b.Width * 3;
int nWidth = b.Width * 3;
int nPixel = 0;
for (int y = 0; y < b.Height; ++y)
{
for (int x = 0; x < nWidth; ++x)
{
nPixel = (int)System.Math.Sqrt((p[0] * p[0]) + (p2[0] * p2[0]));
if (nPixel < nThreshold) nPixel = nThreshold;
if (nPixel > 255) nPixel = 255;
p[0] = (byte)nPixel;
++p;
++p2;
}
p += nOffset;
p2 += nOffset;
}
}
}
catch
{ throw; }
finally
{
b.UnlockBits(bmpData);
bTemp.UnlockBits(bmpData2);
}
}
return b;
}
public static Bitmap EmbossLaplacian(Bitmap b)
{
ConvMatrix m = new ConvMatrix(-1);
m.TopMid = m.MidLeft = m.MidRight = m.BottomMid = 0;
m.Pixel = 4;
m.Offset = 127;
return BitmapFilter.Conv3x3(b, m);
}
public static Bitmap Sharpen(Bitmap b, int nWeight)
{
ConvMatrix m = new ConvMatrix(0);
m.Pixel = nWeight;
m.TopMid = m.MidLeft = m.MidRight = m.BottomMid = -2;
m.Factor = nWeight - 8;
return BitmapFilter.Conv3x3(b, m);
}
public static Bitmap MeanRemoval(Bitmap b, int nWeight)
{
ConvMatrix m = new ConvMatrix(-1);
m.Pixel = nWeight;
m.Factor = nWeight - 8;
return BitmapFilter.Conv3x3(b, m);
}
public static Bitmap Smooth(Bitmap b, int nWeight)
{
ConvMatrix m = new ConvMatrix(1);
m.Pixel = nWeight;
m.Factor = nWeight + 8;
return BitmapFilter.Conv3x3(b, m);
}
public static Bitmap Conv3x3(Bitmap b, ConvMatrix m)
{
// Avoid divide by zero errors.
if (m.Factor == 0)
throw new ArgumentException("Conversion matrix factor must be greater than zero.", "m");
Bitmap bmpDest = new Bitmap(b.Width, b.Height);
// GDI+ lies - the return format is BGR, not RGB (stupid little-endian)
BitmapData bitData = bmpDest.LockBits(new Rectangle(0, 0, bmpDest.Width, bmpDest.Height), ImageLockMode.ReadWrite, PixelFormat.Format24bppRgb);
BitmapData bitSrc = b.LockBits(new Rectangle(0, 0, b.Width, b.Height), ImageLockMode.ReadOnly, PixelFormat.Format24bppRgb);
try
{
int stride = bitSrc.Stride;
int stride2 = bitSrc.Stride * 2;
unsafe
{
for (int y = 0; y < b.Height - 2; y++)
{
byte* ptrSrc = (byte*)bitSrc.Scan0 + y * bitSrc.Stride;
byte* ptrDest = (byte*)bitSrc.Scan0 + y * bitData.Stride;
for (int x = 0; x < b.Width - 2; x++)
{
// Set R channel (remember, bytes are BGR, not RGB, thanks to little endian byte order).
int nPixelR = (((ptrSrc[x * 3 + 2] * m.TopLeft) + (ptrSrc[x * 3 + 5] * m.TopMid) + (ptrSrc[x * 3 + 8] * m.TopRight) +
(ptrSrc[x * 3 + 2 + stride] * m.MidLeft) + (ptrSrc[x * 3 + 5 + stride] * m.Pixel) + (ptrSrc[x * 3 + 8 + stride] * m.MidRight) +
(ptrSrc[x * 3 + 2 + stride2] * m.BottomLeft) + (ptrSrc[x * 3 + 5 + stride2] * m.BottomMid) + (ptrSrc[x * 3 + 8 + stride2] * m.BottomRight)) / m.Factor) + m.Offset;
nPixelR = (int)System.Math.Max(0, System.Math.Min(255, nPixelR));
ptrDest[5 + stride] = (byte)nPixelR;
// Set G channel.
int nPixelG = (((ptrSrc[x * 3 + 1] * m.TopLeft) + (ptrSrc[x * 3 + 4] * m.TopMid) + (ptrSrc[x * 3 + 7] * m.TopRight) +
(ptrSrc[x * 3 + 1 + stride] * m.MidLeft) + (ptrSrc[x * 3 + 4 + stride] * m.Pixel) + (ptrSrc[x * 3 + 7 + stride] * m.MidRight) +
(ptrSrc[x * 3 + 1 + stride2] * m.BottomLeft) + (ptrSrc[x * 3 + 4 + stride2] * m.BottomMid) + (ptrSrc[x * 3 + 7 + stride2] * m.BottomRight)) / m.Factor) + m.Offset;
nPixelG = (int)System.Math.Max(0, System.Math.Min(255, nPixelG));
ptrDest[4 + stride] = (byte)nPixelG;
// Set B channel.
int nPixelB = (((ptrSrc[x * 3 + 0] * m.TopLeft) + (ptrSrc[x * 3 + 3] * m.TopMid) + (ptrSrc[x * 3 + 6] * m.TopRight) +
(ptrSrc[x * 3 + 0 + stride] * m.MidLeft) + (ptrSrc[x * 3 + 3 + stride] * m.Pixel) + (ptrSrc[x * 3 + 6 + stride] * m.MidRight) +
(ptrSrc[x * 3 + 0 + stride2] * m.BottomLeft) + (ptrSrc[x * 3 + 3 + stride2] * m.BottomMid) + (ptrSrc[x * 3 + 6 + stride2] * m.BottomRight)) / m.Factor) + m.Offset;
nPixelB = (int)System.Math.Max(0, System.Math.Min(255, nPixelB));
ptrDest[3 + stride] = (byte)nPixelB;
}
}
}
}
catch
{
if (bmpDest != null)
bmpDest.Dispose();
throw;
}
finally
{
bmpDest.UnlockBits(bitData);
b.UnlockBits(bitSrc);
}
return bmpDest;
}
