C#图像边缘检测（Roberts）的方法

本文实例讲述了c#图像边缘检测（roberts）的方法。分享给大家供大家参考。具体如下：

//定义roberts算子函数
private static bitmap robert(bitmap a)
{
 int w = a.width;
 int h = a.height;
 try
 {
  bitmap dstbitmap = new bitmap(w, h, system.drawing.imaging.pixelformat.format24bpprgb);
  system.drawing.imaging.bitmapdata srcdata = a.lockbits(new rectangle
   (0, 0, w, h), system.drawing.imaging.imagelockmode.readonly, system.drawing.imaging.pixelformat.format24bpprgb);
  system.drawing.imaging.bitmapdata dstdata = dstbitmap.lockbits(new rectangle
   (0, 0, w, h), system.drawing.imaging.imagelockmode.writeonly, system.drawing.imaging.pixelformat.format24bpprgb);
  unsafe
  {
   byte* pin = (byte*)srcdata.scan0.topointer();
   byte* pout = (byte*)dstdata.scan0.topointer();
   byte* p;
   int stride = srcdata.stride;
   for (int y = 0; y < h; y++)
   {
   for (int x = 0; x < w; x++)
   {
    //边缘八个点像素不变
    if (x == 0 || x == w - 1 || y == 0 || y == h - 1)
    {
    pout[0] = pin[0];
    pout[1] = pin[1];
    pout[2] = pin[2];
    }
    else
    {
    int r0, r5, r6, r7;
    int g5, g6, g7, g0;
    int b5, b6, b7, b0;
    double vr, vg, vb;
    //右
    p = pin + 3;
    r5 = p[2];
    g5 = p[1];
    b5 = p[0];
    //左下
    p = pin + stride - 3;
    r6 = p[2];
    g6 = p[1];
    b6 = p[0];
    //正下
    p = pin + stride;
    r7 = p[2];
    g7 = p[1];
    b7 = p[0];
    //中心点
    p = pin;
    r0 = p[2];
    g0 = p[1];
    b0 = p[0];
    vr = (double)(math .abs (r0-r5)+math .abs ( r5-r7));
    vg = (double)(math.abs(g0 - g5) + math.abs(g5 - g7));
    vb = (double)(math.abs(b0 - b5) + math.abs(b5 - b7));
    if (vr > 0)
    {
     vr = math.min(255, vr);
    }
    else
    {
     vr = math.max(0, vr);
    }
    if (vg > 0)
    {
     vg = math.min(255, vg);
    }
    else
    {
     vg = math.max(0, vg);
    }
    if (vb > 0)
    {
     vb = math.min(255, vb);
    }
    else
    {
     vb = math.max(0, vb);
    }
    pout[0] = (byte)vb;
    pout[1] = (byte)vg;
    pout[2] = (byte)vr;
    }
    pin += 3;
    pout += 3;
   }
   pin += srcdata.stride - w * 3;
   pout += srcdata.stride - w * 3;
   }
  }
  a.unlockbits(srcdata);
  dstbitmap.unlockbits(dstdata);
  return dstbitmap;
 }
 catch
 {
  return null;
 }
}

希望本文所述对大家的c#程序设计有所帮助。