Win8Metro(C#)数字图像处理--2.14Prewitt 边缘检测

原文:Win8Metro(C#)数字图像处理--2.14Prewitt 边缘检测



[函数名称]

图像Prewitt边缘检测函数PrewittEdgeProcess(WriteableBitmap
src)

[函数代码]

       ///<summary>

       ///
Smooth edge detection.

       ///</summary>

       ///<param
name="src">Source image.</param>

       ///<returns></returns>

       publicstaticWriteableBitmap
PrewittEdgeProcess(WriteableBitmap src)////14
Prewitt边缘检测

       {

           if(src!=null
)

           {

           int
w = src.PixelWidth;

           int
h = src.PixelHeight;

           WriteableBitmap
smoothImage =newWriteableBitmap(w,h);

           byte[]
temp = src.PixelBuffer.ToArray();

           byte[]
tempMask = (byte[])temp.Clone();

           int
b = 0, g = 0, r = 0;

           for
(int j = 1; j < h - 1; j++)

           {

               for
(int i = 4; i < w * 4 - 4; i += 4)

               {

                   if
(i == 0 || i == w - 4 || j == 0 || j == h - 1)

                   {

                       temp[i + j * w * 4] = (byte)0;

                       temp[i + 1 + j * w * 4] = (byte)0;

                       temp[i + 2 + j * w * 4] = (byte)0;

                   }

                   else

                   {

                       b =Math.Abs(tempMask[i
- 4 + (j - 1) * w * 4] + tempMask[i + (j - 1) * w * 4] + tempMask[i + 4 + (j - 1) * w * 4]

                           - tempMask[i - 4 + (j + 1) * w * 4] - tempMask[i + (j + 1) *
w * 4] - tempMask[i + 4 + (j + 1) * w * 4]) +

                           Math.Abs(tempMask[i
+ 4 + (j - 1) * w * 4] + tempMask[i + 4 + j * w * 4] + tempMask[i + 4 + (j + 1) * w * 4]

                           - tempMask[i - 4 + (j - 1) * w * 4] - tempMask[i - 4 + j * w
* 4] - tempMask[i - 4 + (j + 1) * w * 4]);

                       g =Math.Abs(tempMask[i
- 4 + 1 + (j - 1) * w * 4] + tempMask[i + 1 + (j - 1) * w * 4] + tempMask[i + 1 + 4 + (j - 1) * w * 4]

                           - tempMask[i - 4 + 1 + (j + 1) * w * 4] - tempMask[i + 1 + (j
+ 1) * w * 4] - tempMask[i + 1 + 4 + (j + 1) * w * 4]) +

                           Math.Abs(tempMask[i
+ 1 + 4 + (j - 1) * w * 4] + tempMask[i + 1 + 4 + j * w * 4] + tempMask[i + 1 + 4 + (j + 1) * w * 4]

                           - tempMask[i - 4 + 1 + (j - 1) * w * 4] - tempMask[i - 4 + 1
+ j * w * 4] - tempMask[i - 4 + 1 + (j + 1) * w * 4]);

                       r =Math.Abs(tempMask[i
- 4 + 2 + (j - 1) * w * 4] + tempMask[i + 2 + (j - 1) * w * 4] + tempMask[i + 4 + 2 + (j - 1) * w * 4]

                           - tempMask[i - 4 + 2 + (j + 1) * w * 4] - tempMask[i + 2 + (j
+ 1) * w * 4] - tempMask[i + 4 + 2 + (j + 1) * w * 4]) +

                           Math.Abs(tempMask[i
+ 4 + 2 + (j - 1) * w * 4] + tempMask[i + 4 + 2 + j * w * 4] + tempMask[i + 4 + 2 + (j + 1) * w * 4]

                           - tempMask[i - 4 + 2 + (j - 1) * w * 4] - tempMask[i - 4 + 2
+ j * w * 4] - tempMask[i - 4 + 2 + (j + 1) * w * 4]);

                       temp[i + j * w * 4] = (byte)(b
> 0 ? (b < 255 ? b : 255) : 0);

                       temp[i + 1 + j * w * 4] = (byte)(g
> 0 ? (g < 255 ? g : 255) : 0);

                       temp[i + 2 + j * w * 4] = (byte)(r
> 0 ? (r < 255 ? r : 255) : 0);

                   }

                   b = 0; g = 0; r = 0;

               }

           }

           Stream
sTemp = smoothImage.PixelBuffer.AsStream();

           sTemp.Seek(0,SeekOrigin.Begin);

           sTemp.Write(temp, 0, w * 4 * h);

           return
smoothImage;

           }

           else

           {

               returnnull;

           }  

       }