验证码识别常用算法

1、验证码识别常用算法图像处理（验证码识别）程序中常用算法：灰度，二值化，去噪（1*1像素或者 3*3 像素等） 代码：view plaincopy to clipboardprint?/ 灰度private void btnGray_Click( object sender, EventArgs e) tryint Height = this .picBase.Image.Height;int Width = this .picBase.Image.Width; Bitmap newbitmap = newBitmap(Width, Height); Bitmap oldbitmap = (Bi

2、tmap)this .picBase.Image;Color pixel;for ( int x = 0; x Width; x+)for ( int y = 0; y Height; y+) pixel = oldbitmap.GetPixel(x, y);newbitmap.SetPixel(x, y, Gray(pixel); this .picBase.Image = newbitmap; catch (Exception err) MessageBox.Show( 灰度化失败 原因： + err.Message);/ 灰度化算法protected static Color Gray(

3、Color c)int rgb = Convert.ToInt32(double )(0.3 * c.R) + (0.59 * c.G) + (0.11 * c.B);return Color.FromArgb(rgb, rgb, rgb);/ 灰度private void btnGray_Click( object sender, EventArgs e) tryint Height = this .picBase.Image.Height; int Width = this .picBase.Image.Width;Bitmap newbitmap =newBitmap(Width, He

4、ight);Bitmap oldbitmap = (Bitmap)this .picBase.Image;Color pixel;for ( int x = 0; x Width; x+)for ( int y = 0; y Height; y+) pixel = oldbitmap.GetPixel(x, y);newbitmap.SetPixel(x, y, Gray(pixel);this .picBase.Image = newbitmap;catch (Exception err)MessageBox.Show( 灰度化失败 原因： + err.Message);/ 灰度化算法pro

5、tected static Color Gray(Color c)int rgb = Convert.ToInt32( double )(0.3 * c.R) + (0.59 * c.G) + (0.11 * c.B); return Color.FromArgb(rgb, rgb, rgb);图像二值化 效果图： 代码：view plaincopy to clipboardprint?/ 二值化private void btnDobleValue_Click( object sender, EventArgs e)this .picBase.Image = Binarizate(Bitmap

6、) this .picBase.Image);public static Bitmap Binarizate(Bitmap map)int tv = ComputeThresholdValue(map);int x = map.Width;int y = map.Height;for ( int i = 0; i x; i+)for ( int j = 0; j = tv) map.SetPixel(i, j, Color.FromArgb(0xff, 0xff, 0xff);else map.SetPixel(i, j, Color.FromArgb(0, 0, 0);return map;

7、/ 二值化 private void btnDobleValue_Click( object sender, EventArgs e)this .picBase.Image);this .picBase.Image = Binarizate(Bitmap)public static Bitmap Binarizate(Bitmap map) int tv = ComputeThresholdValue(map);int x = map.Width;int y = map.Height;for ( int i = 0; i x; i+)for ( int j = 0; j = tv)map.Se

8、tPixel(i, j, Color.FromArgb(0xff, 0xff, 0xff); elsemap.SetPixel(i, j, Color.FromArgb(0, 0, 0); return map;图像去噪( 1*1 像素) 效果图： 代码：view plaincopy to clipboardprint?private void btnClean11_Click( object sender, EventArgs e) this .picBase.Image = OperateBitmap.ClearNoise(Bitmap)this .picBase.Image,4);/1*

9、1 除噪public static Bitmap ClearNoise(Bitmap bitmap,int MaxNearPoints)Color piexl;int nearDots = 0;/int XSpan, YSpan, tmpX, tmpY;/ 逐点判断for ( int i = 0; i bitmap.Width; i+)for ( int j = 0; j bitmap.Height; j+)piexl = bitmap.GetPixel(i, j);if (piexl.R != 255)nearDots = 0;/ 判断周围 8个点是否全为空边框全去掉 bitmap.SetP

10、ixel(i, j, Color.FromArgb(255, 255, 255);elseif (bitmap.GetPixel(i - 1, j - 1).R != 255 ) nearDots+;if (bitmap.GetPixel(i, j - 1).R != 255) nearDots+; if (bitmap.GetPixel(i + 1, j - 1).R != 255) nearDots+; if (bitmap.GetPixel(i - 1, j).R != 255) nearDots+; if (bitmap.GetPixel(i + 1, j).R != 255) nea

11、rDots+; if (bitmap.GetPixel(i - 1, j + 1).R != 255) nearDots+; if (bitmap.GetPixel(i, j + 1).R != 255) nearDots+; if (bitmap.GetPixel(i + 1, j + 1).R != 255) nearDots+; if (nearDots 4)bitmap.SetPixel(i, j, Color.FromArgb(255, 255, 255); / 去掉单点 & 粗细小 3邻边点 else / 背景bitmap.SetPixel(i, j, Color.FromArgb

12、(255, 255, 255);return bitmap;private void btnClean11_Click( object sender, EventArgs e)this .picBase.Image = OperateBitmap.ClearNoise(Bitmap)this .picBase.Image,4);/1*1 除噪public static Bitmap ClearNoise(Bitmap bitmap,int MaxNearPoints)Color piexl;int nearDots = 0;/int XSpan, YSpan, tmpX, tmpY;/ 逐点判

13、断for ( int i = 0; i bitmap.Width; i+)for ( int j = 0; j bitmap.Height; j+)piexl = bitmap.GetPixel(i, j);if (piexl.R != 255)nearDots = 0;/ 判断周围 8个点是否全为空if (i = 0 | i = bitmap.Width - 1 | j = 0 | j = bitmap.Height - 1)/边框全去掉bitmap.SetPixel(i, j, Color.FromArgb(255, 255, 255);elseif (bitmap.GetPixel(i

14、- 1, j - 1).R != 255 ) nearDots+;if (bitmap.GetPixel(i, j - 1).R != 255) nearDots+;if (bitmap.GetPixel(i + 1, j - 1).R != 255) nearDots+;if (bitmap.GetPixel(i - 1, j).R != 255) nearDots+;if (bitmap.GetPixel(i + 1, j).R != 255) nearDots+;if (bitmap.GetPixel(i - 1, j + 1).R != 255) nearDots+;if (bitmap.GetPixel(i, j + 1).R != 255) nearDots+;if (bitmap.GetPixel(i + 1,