C#验证码识别代码分享
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验证码识别了：
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
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 UnBitmap 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>privateint 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>publicvoid 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>publicvoid 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>publicvoid 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 =newint[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>publicvoid 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1if (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>publicvoid 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)returnnull;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>publicstring 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; } }
}