Methods of image binarization (color to black and white) in C# digital image processing

//Define image binarization functionprivate static Bitmap PBinary(Bitmap src,int v)
{
 int w = ;
 int h = ;
 Bitmap dstBitmap = new Bitmap( , ,System .Drawing .Imaging .PixelFormat .Format24bppRgb );
  srcData = (new Rectangle(0, 0, w, h), , .Format24bppRgb);
  dstData = (new Rectangle(0, 0, w, h), , .Format24bppRgb);
 unsafe
 {
  byte* pIn = (byte*)srcData.();
  byte* pOut = (byte*)dstData.();
  byte* p;
  int stride = ;
  int r, g, b;
  for (int y = 0; y < h; y++)
  {
  for (int x = 0; x < w; x++)
  {
   p = pIn;
   r = p[2];
   g = p[1];
   b = p[0];
   pOut [0]=pOut [1]=pOut [2]=(byte)(((byte)(0.2125 * r + 0.7154 * g + 0.0721 * b) >= v)
   ? 255 : 0);
   pIn += 3;
   pOut += 3;
  }
  pIn +=  - w * 3;
  pOut +=  - w * 3;
  }
  (srcData );
  (dstData );
  return dstBitmap;
 }
}