用于验证码图片识别的类（C#源码）

最近写了几个网站的验证码图片自动识别程序，尽管每个网站的验证码图片都不相同，识别的方法有所差别。但写得多了，也总结出不少相同之处。今天抽空封装出一个基础类来，发现可以很好地重复利用，编写不同的验证码识别程序，效率提高了不少。好东东不能独享，现放出来供大家共同研究，请网友们妥善用之。

封装后的类使用很简单，针对不同的验证码，相应继承修改某些方法，即可简单几句代码就可以实现图片识别了：

GrayByPixels(); //灰度处理

GetPicValidByValue(128, 4); //得到有效空间

Bitmap[] pics = GetSplitPics(4, 1); //分割

string code = GetSingleBmpCode(pics[i], 128); //得到代码串

具体使用，请参见我做的例子：

投票程序示例.exe 投票程序源码

（例子说明：使用进程投票，可自动清除Alert弹出窗口，可自动换IP，ADSL用户自行修改Restart.bat中第三行内容）


using System;


using System.Collections.Generic;


using System.Text;


using System.Collections;


using System.Drawing;


using System.Drawing.Imaging;


using System.Runtime.InteropServices;




namespace BallotAiying2


{


class UnCodebase


{


public Bitmap bmpobj;


public UnCodebase(Bitmap pic)


{


bmpobj = new Bitmap(pic); //转换为Format32bppRgb


}




/// <summary>


/// 根据RGB，计算灰度值


/// </summary>


/// <param name="posClr">Color值</param>


/// <returns>灰度值，整型</returns>


private int GetGrayNumColor(System.Drawing.Color posClr)


{


return (posClr.R * 19595 + posClr.G * 38469 + posClr.B * 7472) >> 16;


}




/// <summary>


/// 灰度转换,逐点方式


/// </summary>


public void GrayByPixels()


{


for (int i = 0; i < bmpobj.Height; i++)


{


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


{


int tmpValue = GetGrayNumColor(bmpobj.GetPixel(j, i));


bmpobj.SetPixel(j, i, Color.FromArgb(tmpValue, tmpValue, tmpValue));


}


}


}




/// <summary>


/// 去图形边框


/// </summary>


/// <param name="borderWidth"></param>


public void ClearPicBorder(int borderWidth)


{


for (int i = 0; i < bmpobj.Height; i++)


{


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


{


if (i < borderWidth || j < borderWidth || j > bmpobj.Width - 1 - borderWidth || i > bmpobj.Height - 1 - borderWidth)


bmpobj.SetPixel(j, i, Color.FromArgb(255, 255, 255));


}


}


}




/// <summary>


/// 灰度转换,逐行方式


/// </summary>


public void GrayByLine()


{


Rectangle rec = new Rectangle(0, 0, bmpobj.Width, bmpobj.Height);


BitmapData bmpData = bmpobj.LockBits(rec, ImageLockMode.ReadWrite, bmpobj.PixelFormat);// PixelFormat.Format32bppPArgb);


// bmpData.PixelFormat = PixelFormat.Format24bppRgb;


IntPtr scan0 = bmpData.Scan0;


int len = bmpobj.Width * bmpobj.Height;


int[] pixels = new int[len];


Marshal.Copy(scan0, pixels, 0, len);




//对图片进行处理


int GrayValue = 0;


for (int i = 0; i < len; i++)


{


GrayValue = GetGrayNumColor(Color.FromArgb(pixels[i]));


pixels[i] = (byte)(Color.FromArgb(GrayValue, GrayValue, GrayValue)).ToArgb(); //Color转byte


}




bmpobj.UnlockBits(bmpData);


}




/// <summary>


/// 得到有效图形并调整为可平均分割的大小


/// </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 CharsCount)


{


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;


};


};


};


// 确保能整除


int Span = CharsCount - (posx2 - posx1 + 1) % CharsCount; //可整除的差额数


if (Span < CharsCount)


{


int leftSpan = Span / 2; //分配到左边的空列 ，如span为单数,则右边比左边大1


if (posx1 > leftSpan)


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)


{


int posx1 = singlepic.Width; int posy1 = singlepic.Height;


int posx2 = 0; int posy2 = 0;


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


{


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


{


int pixelValue = singlepic.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);


return singlepic.Clone(cloneRect, singlepic.PixelFormat);


}




/// <summary>


/// 平均分割图片


/// </summary>


/// <param name="RowNum">水平上分割数</param>


/// <param name="ColNum">垂直上分割数</param>


/// <returns>分割好的图片数组</returns>


public Bitmap [] GetSplitPics(int RowNum,int ColNum)


{


if (RowNum == 0 || ColNum == 0)


return null;


int singW = bmpobj.Width / RowNum;


int singH = bmpobj.Height / ColNum;


Bitmap [] PicArray=new Bitmap[RowNum*ColNum];




Rectangle cloneRect;


for (int i = 0; i < ColNum; i++) //找有效区


{


for (int j = 0; j < RowNum; j++)


{


cloneRect = new Rectangle(j*singW, i*singH, singW , singH);


PicArray[i*RowNum+j]=bmpobj.Clone(cloneRect, bmpobj.PixelFormat);//复制小块图


}


}


return PicArray;


}




/// <summary>


/// 返回灰度图片的点阵描述字串，1表示灰点，0表示背景


/// </summary>


/// <param name="singlepic">灰度图</param>


/// <param name="dgGrayValue">背前景灰色界限</param>


/// <returns></returns>


public string GetSingleBmpCode(Bitmap singlepic, int dgGrayValue)


{


Color piexl;


string code = "";


for (int posy = 0; posy < singlepic.Height; posy++)


for (int posx = 0; posx < singlepic.Width; posx++)


{


piexl = singlepic.GetPixel(posx, posy);


if (piexl.R < dgGrayValue) // Color.Black )


code = code + "1";


else


code = code + "0";


}


return code;


}


}


}