c#实现识别图片上的验证码数字

posx1 = posx1 - leftSpan; if (posx2 + Span - leftSpan < bmpobj.Width)

posx2 = posx2 + Span - leftSpan; }

//复制新图 Rectangle cloneRect = new Rectangle(posx1, posy1, posx2 - posx1 + 1, posy2 - posy1 + 1);

bmpobj = bmpobj.Clone(cloneRect, bmpobj.PixelFormat); }

/// <summary>

/// 得到有效图形,图形为类变量 /// </summary>

/// <param name="dgGrayValue">灰度背景分界值</param> /// <param name="CharsCount">有效字符数</param>

/// <returns></returns> public void GetPicValidByValue(int dgGrayValue)

{ int posx1 = bmpobj.Width; int posy1 = bmpobj.Height;

int posx2 = 0; int posy2 = 0; for (int i = 0; i < bmpobj.Height; i++) //找有效区

{ for (int j = 0; j < bmpobj.Width; j++)

{ int pixelValue = bmpobj.GetPixel(j, i).R;

if (pixelValue < dgGrayValue) //根据灰度值 {

if (posx1 > j) posx1 = j; if (posy1 > i) posy1 = i;

if (posx2 < j) posx2 = j;

if (posy2 < i) posy2 = i; };

}; };

//复制新图 Rectangle cloneRect = new Rectangle(posx1, posy1, posx2 - posx1 + 1, posy2 - posy1 + 1);

bmpobj = bmpobj.Clone(cloneRect, bmpobj.PixelFormat); }

/// <summary>

/// 得到有效图形,图形由外面传入 /// </summary>

/// <param name="dgGrayValue">灰度背景分界值</param> /// <param name="CharsCount">有效字符数</param>

/// <returns></returns> public Bitmap GetPicValidByValue(Bitmap singlepic, int dgGrayValue)