public static void Conv3x3(Bitmap b, ConvMatrix m)
{
if (0 == m.Factor) return;
Bitmap bSrc = (Bitmap)b.Clone();
BitmapData bmData = b.LockBits(new Rectangle(0, 0, b.Width, b.Height), ImageLockMode.ReadWrite, PixelFormat.Format24bppRgb);
BitmapData bmSrc = bSrc.LockBits(new Rectangle(0, 0, bSrc.Width, bSrc.Height), ImageLockMode.ReadWrite, PixelFormat.Format24bppRgb);
int stride = bmData.Stride;
int stride2 = stride * 2;
unsafe
{
byte* pData = (byte*)bmData.Scan0;
byte* pSrc = (byte*)bmSrc.Scan0;
int nOffset = stride + 6 - b.Width * 3;
int nWidth = b.Width - 2;
int nHeight = b.Height - 2;
for (int y = 0; y < nHeight; ++y)
{
for (int x = 0; x < nWidth; ++x)
{
int nPixel = ((((pSrc[2] * m.TopLeft) + (pSrc[5] * m.TopMid) + (pSrc[8] * m.TopRight) +
(pSrc[2 + stride] * m.MidLeft) + (pSrc[5 + stride] * m.Pixel) + (pSrc[8 + stride] * m.MidRight) +
(pSrc[2 + stride2] * m.BottomLeft) + (pSrc[5 + stride2] * m.BottomMid) + (pSrc[8 + stride2] * m.BottomRight)) / m.Factor) + m.Offset);
pData[5 + stride] = (byte)Math.Max(0, Math.Min(nPixel, 255));
nPixel = ((((pSrc[1] * m.TopLeft) + (pSrc[4] * m.TopMid) + (pSrc[7] * m.TopRight) +
(pSrc[1 + stride] * m.MidLeft) + (pSrc[4 + stride] * m.Pixel) + (pSrc[7 + stride] * m.MidRight) +
(pSrc[1 + stride2] * m.BottomLeft) + (pSrc[4 + stride2] * m.BottomMid) + (pSrc[7 + stride2] * m.BottomRight)) / m.Factor) + m.Offset);
pData[4 + stride] = (byte)Math.Max(0, Math.Min(nPixel, 255));
nPixel = ((((pSrc[0] * m.TopLeft) + (pSrc[3] * m.TopMid) + (pSrc[6] * m.TopRight) +
(pSrc[0 + stride] * m.MidLeft) + (pSrc[3 + stride] * m.Pixel) + (pSrc[6 + stride] * m.MidRight) +
(pSrc[0 + stride2] * m.BottomLeft) + (pSrc[3 + stride2] * m.BottomMid) + (pSrc[6 + stride2] * m.BottomRight)) / m.Factor) + m.Offset);
pData[3 + stride] = (byte)Math.Max(0, Math.Min(nPixel, 255));
pData += 3;
pSrc += 3;
}
pData += nOffset;
pSrc += nOffset;
}
}
b.UnlockBits(bmData);
bSrc.UnlockBits(bmSrc);
}
public static void 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;
Conv3x3(b, m);
}
public static void Sharpen(Bitmap b, int nWeight /* default to 11*/ )
{
ConvMatrix m = new ConvMatrix();
m.SetAll(0);
m.Pixel = nWeight;
m.TopMid = m.MidLeft = m.MidRight = m.BottomMid = -2;
m.Factor = nWeight - 8;
Conv3x3(b, m);
}
public static void Smooth(Bitmap b, int nWeight /* default to 1 */)
{
ConvMatrix m = new ConvMatrix();
m.SetAll(1);
m.Pixel = nWeight;
m.Factor = nWeight + 8;
Conv3x3(b, m);
}
public static void GaussianBlur(Bitmap b, int nWeight /* default to 4*/)
{
ConvMatrix m = new ConvMatrix();
m.SetAll(1);
m.Pixel = nWeight;
m.TopMid = m.MidLeft = m.MidRight = m.BottomMid = 2;
m.Factor = nWeight + 12;
Conv3x3(b, m);
}
