C#图像处理之边缘检测(Sobel)的方法
本文实例讲述了C#图像处理之边缘检测(Sobel)的方法。分享给大家供大家参考。具体如下:
//定义sobel算子函数 private static Bitmap sobel(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, r1, r2, r3, r4, r5, r6, r7, r8; int g1, g2, g3, g4, g5, g6, g7, g8, g0; int b1, b2, b3, b4, b5, b6, b7, b8, b0; double vR, vG, vB; //左上 p = pIn - stride - 3; r1 = p[2]; g1 = p[1]; b1 = p[0]; //正上 p = pIn - stride; r2 = p[2]; g2 = p[1]; b2 = p[0]; //右上 p = pIn - stride + 3; r3 = p[2]; g3 = p[1]; b3 = p[0]; //左 p = pIn - 3; r4 = p[2]; g4 = p[1]; b4 = p[0]; //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]; // 右下 p = pIn + stride + 3; r8 = p[2]; g8 = p[1]; b8 = p[0]; //中心点 p = pIn; r0 = p[2]; g0 = p[1]; b0 = p[0]; //使用模板 vR = (double)(Math .Abs (r1+2*r4+r6-r3-2*r5-r8)+Math .Abs (r1+2*r2+r3-r6-2*r7-r8)); vG = (double)(Math .Abs (g1+2*g4+g6-g3-2*g5-g8)+Math .Abs (g1+2*g2+g3-g6-2*g7-g8)); vB = (double)(Math .Abs (b1+2*b4+b6-b3-2*b5-b8)+Math .Abs (b1+2*b2+b3-b6-2*b7-b8)); 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。
赞 (0)