验证码识别

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Text;

using System.Windows.Forms;

using System.IO;

using System.Web.UI.HtmlControls;

using mshtml;

using System.Drawing.Imaging;

namespace ReadImageCode

{

    public partial class Form1 : Form

    {

        public Form1()

        {

            InitializeComponent();

        }

        private string url_1 = "http://www.fjjj.gov.cn/chs/jf_main.asp?t=1";

        private string url_2 = "http://www.fjjj.gov.cn/article/getcode.asp";





        private void Form1_Load(object sender, EventArgs e)

        {

            this.webBrowser1.Navigate(url_1);

        }



        private void webBrowser1_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)

        {

            HTMLDocument doc = (HTMLDocument)this.webBrowser1.Document.DomDocument;

            IHTMLControlRange range = (IHTMLControlRange)((HTMLBody)doc.body).createControlRange();

            IHTMLControlElement codeimg = null;

            foreach (IHTMLImgElement img in doc.images)

            {

                if (img.src.ToLower().IndexOf(url_2.ToLower())!=-1)

                    codeimg = (IHTMLControlElement)img;

            }

            range.add(codeimg);

            range.execCommand("Copy", false, null);

            codeimg = null;

            range = null;

            doc = null;

            if (Clipboard.ContainsImage())

            {

                this.pictureBox1.Image = Clipboard.GetImage();

                MemoryStream ns = new MemoryStream();

                this.pictureBox1.Image.Save(ns, ImageFormat.Bmp);

                Bitmap sourcebm =  (Bitmap)(Bitmap.FromStream(ns));

                sourcebm=ConvertToGrayscale(sourcebm);

                sourcebm = ConvertToMonochrome(sourcebm);

                this.pictureBox1.Image = (Image)sourcebm;

                string codestr = this.GetCodeString(sourcebm);

                this.codeLabel.Text = this.GetCodeNumber(codestr);//数字验证码

                //this.textBox1.Text += codestr + System.Environment.NewLine + System.Environment.NewLine;

                ns = null;

                sourcebm = null;



            }

            else

            {

                MessageBox.Show("读取失败");

            }

            Clipboard.Clear();

        }



        private Bitmap ConvertToGrayscale(Bitmap sourcebm)

        {

            //将彩色转换为灰度

            for (int x = 0; x < sourcebm.Width; x++)

            {

                for (int y = 0; y < sourcebm.Height; y++)

                {

                    Color c = sourcebm.GetPixel(x, y);

                    int luma = (int)(c.R * 0.3 + c.G * 0.59 + c.B * 0.11);//转换灰度的算法

                    sourcebm.SetPixel(x, y, Color.FromArgb(luma, luma, luma));

                }

            }

            return sourcebm;

        }

        byte critical_value = 238;//灰色背景色



        private Bitmap ConvertToMonochrome(Bitmap sourcebm)

        {

            

            //去杂色，转换为黑白图片

            for (int x = 0; x < sourcebm.Width; x++)

            {

                for (int y = 0; y < sourcebm.Height; y++)

                {

                    Color c = sourcebm.GetPixel(x, y);

                    if (c.R == 238)

                        sourcebm.SetPixel(x, y, Color.FromArgb(255, 255, 255));

                    else

                        sourcebm.SetPixel(x, y, Color.FromArgb(0, 0, 0));

                }

            }

            return sourcebm;

        }



        private string GetCodeString(Bitmap sourcebm)

        {

            int[] widthStartX = new int[40];//图片宽40像素

            int[] widthEndX = new int[40];

            bool myColumn = true;

            bool charStart = true;

            int charNum = 0;

            for (int x = 0; x < sourcebm.Width; x++)

            {

                myColumn = true;

                for (int y = 0; y < sourcebm.Height; y++)

                {

                    Color c = sourcebm.GetPixel(x, y);

                    if (c.R == 0 && charStart == false)//第一次出现黑点

                    {

                        widthStartX[charNum] = x;

                        charStart = true;

                        break;

                    }

                    if (c.R == 0 && charStart == true)//后续出现黑点

                    {

                        myColumn = false;

                        break;

                    }

                }

                if (myColumn == true && charStart == true && widthStartX[charNum] < x)//如果当列没有黑点并且前面出现过黑点还没结束

                {

                    widthEndX[charNum] = x - 1;

                    charStart = false;

                    charNum++;

                }

                if (charStart == true && myColumn == false && x == (sourcebm.Width - 1))//如果开始出现黑点了,并且最后一列也有黑点

                {

                    widthEndX[charNum] = x;

                    charStart = false;

                    charNum++;

                }

            }

            string str = "";

            int sp = 0;

            for (int x = 0; x < sourcebm.Width; x++)

            {

                for (int y = 0; y < sourcebm.Height; y++)

                {

                    sp++;

                    Color c1 = sourcebm.GetPixel(x, y);

                    if (c1.R == 0)

                        str = str + "1";

                    else

                        str = str + "0";

                    if (sp == 100)

                    {

                        sp = 0;

                        str = str + "|";//由此可分析出数字组成部分，即numstr

                    }

                }

            }

            return str;            

        }



        private string GetCodeNumber(string str)

        {

            string[] num = str.Split('|');

            return GetNum(num[0]) + GetNum(num[1]) + GetNum(num[2]) + GetNum(num[3]);

        }



        private string GetNum(string str)

        {

            string ret = "0";

            for (int i = 0; i < numstr.Length; i++)

            {

                if (numstr[i] == str)

                {

                    ret =  i.ToString();

                    break;

                }

            }

            return ret;

        }



        private string[] numstr = {

            "0111111110100000000110000000011000000001100000000101111111100000000000000000000000000000000000000000",//0

            "0100000001010000000111111111110000000001000000000100000000000000000000000000000000000000000000000000",//1

            "0100000011100000010110000010011000010001100010000101110000010000000000000000000000000000000000000000",//2

            "0100000010100000000110001000011000100001100010000101110111100000000000000000000000000000000000000000",//3

            "0000011000000010100000110010000100001001111111111100000010010000000000000000000000000000000000000000",//4

            "1111100010100010000110001000011000100001100010000110000111100000000000000000000000000000000000000000",//5

            "0011111110010001000110001000011000100001100010000100000111100000000000000000000000000000000000000000",//6

            "1100000000100000001110000011001000110000101100000011000000000000000000000000000000000000000000000000",//7

            "0111011110100010000110001000011000100001100010000101110111100000000000000000000000000000000000000000",//8

            "0111100000100001000110000100011000010001100010001001111111000000000000000000000000000000000000000000" //9

        };



        private void button1_Click(object sender, EventArgs e)

        {

            string url = url_1;

            url = url + "&rnd=" + DateTime.Now.ToString();

            this.webBrowser1.Navigate(url);

        }

    }

}