public bool Filter(Bitmap b)
{
var m = new SharpMatrix();
return Conv3x3(b, m);
}
public static bool Conv3x3(Bitmap b, SharpMatrix m)
{
// Avoid divide by zero errors
if (0 == m.Factor)
return false; Bitmap
// GDI+ still lies to us - the return format is BGR, NOT RGB.
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;
System.IntPtr Scan0 = bmData.Scan0;
System.IntPtr SrcScan0 = bmSrc.Scan0;
unsafe
{
byte* p = (byte*)(void*)Scan0;
byte* pSrc = (byte*)(void*)SrcScan0;
int nOffset = stride - b.Width * 3;
int nWidth = b.Width - 2;
int nHeight = b.Height - 2;
int nPixel;
for (int y = 0; y < nHeight; ++y)
{
for (int x = 0; x < nWidth; ++x)
{
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);
if (nPixel < 0) nPixel = 0;
if (nPixel > 255) nPixel = 255;
p[5 + stride] = (byte)nPixel;
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);
if (nPixel < 0) nPixel = 0;
if (nPixel > 255) nPixel = 255;
p[4 + stride] = (byte)nPixel;
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);
if (nPixel < 0) nPixel = 0;
if (nPixel > 255) nPixel = 255;
p[3 + stride] = (byte)nPixel;
p += 3;
pSrc += 3;
}
p += nOffset;
pSrc += nOffset;
}
}
b.UnlockBits(bmData);
bSrc.UnlockBits(bmSrc);
return true;
}
