c#實現識別圖片上的驗證碼數字

2019-10-29 21:36:27

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這篇文章主要介紹了c#實現識別圖片上的驗證碼數字的方法，本文給大家匯總了2種方法，有需要的小伙伴可以參考下。

public void imgdo(Bitmap img)

{

//去色

Bitmap btp = img;

Color c = new Color();

int rr, gg, bb;

for (int i = 0; i < btp.Width; i++)

{

for (int j = 0; j < btp.Height; j++)

{

//取圖片當前的像素點

c = btp.GetPixel(i, j);

rr = c.R; gg = c.G; bb = c.B;

//改變顏色

if (rr == 102 && gg == 0 && bb == 0)

{

//重新設置當前的像素點

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

}

if (rr == 153 && gg == 0 && bb == 0)

{

//重新設置當前的像素點

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

} if (rr == 153 && gg == 0 && bb == 51)

{

//重新設置當前的像素點

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

} if (rr == 153 && gg == 43 && bb == 51)

{

//重新設置當前的像素點

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

}

if (rr == 255 && gg == 255 && bb == 0)

{

//重新設置當前的像素點

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

}

if (rr == 255 && gg == 255 && bb == 51)

{

//重新設置當前的像素點

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

}

}

}

btp.Save("d://去除相關顏色.png");

pictureBox2.Image = Image.FromFile("d://去除相關顏色.png");

//灰度

Bitmap bmphd = btp;

for (int i = 0; i < bmphd.Width; i++)

{

for (int j = 0; j < bmphd.Height; j++)

{

//取圖片當前的像素點

var color = bmphd.GetPixel(i, j);

var gray = (int)(color.R * 0.001 + color.G * 0.700 + color.B * 0.250);

//重新設置當前的像素點

bmphd.SetPixel(i, j, Color.FromArgb(gray, gray, gray));

}

}

bmphd.Save("d://灰度.png");

pictureBox27.Image = Image.FromFile("d://灰度.png");

//二值化

Bitmap erzhi = bmphd;

Bitmap orcbmp;

int nn = 3;

int w = erzhi.Width;

int h = erzhi.Height;

BitmapData data = erzhi.LockBits(new Rectangle(0, 0, w, h), ImageLockMode.ReadOnly, PixelFormat.Format24bppRgb);

unsafe

{

byte* p = (byte*)data.Scan0;

byte[,] vSource = new byte[w, h];

int offset = data.Stride - w * nn;

for (int y = 0; y < h; y++)

{

for (int x = 0; x < w; x++)

{

vSource[x, y] = (byte)(((int)p[0] + (int)p[1] + (int)p[2]) / 3);

p += nn;

}

p += offset;

}

erzhi.UnlockBits(data);

Bitmap bmpDest = new Bitmap(w, h, PixelFormat.Format24bppRgb);

BitmapData dataDest = bmpDest.LockBits(new Rectangle(0, 0, w, h), ImageLockMode.WriteOnly, PixelFormat.Format24bppRgb);

p = (byte*)dataDest.Scan0;

offset = dataDest.Stride - w * nn;

for (int y = 0; y < h; y++)

{

for (int x = 0; x < w; x++)

{

p[0] = p[1] = p[2] = (int)vSource[x, y] > 161 ? (byte)255 : (byte)0;

//p[0] = p[1] = p[2] = (int)GetAverageColor(vSource, x, y, w, h) > 50 ? (byte)255 : (byte)0;

p += nn;

}

p += offset;

}

bmpDest.UnlockBits(dataDest);

orcbmp = bmpDest;

orcbmp.Save("d://二值化.png");

pictureBox29.Image = Image.FromFile("d://二值化.png");

}

//OCR的值

if (orcbmp != null)

{

string result = Ocr(orcbmp);

label32.Text = result.Replace("/n", "/r/n").Replace(" ", "");

}

}

C#識別驗證碼圖片通用類

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); //轉換為Format32bppRgb

}

/// <summary>

/// 根據RGB，計算灰度值

/// </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>

/// 灰度轉換,逐點方式

/// </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>

/// 去圖形邊框

/// </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>

/// 灰度轉換,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);

//對圖片進行處理

int GrayValue = 0;

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

{

GrayValue = GetGrayNumColor(Color.FromArgb(pixels));

pixels = (byte)(Color.FromArgb(GrayValue, GrayValue, GrayValue)).ToArgb(); //Color轉byte

}

bmpobj.UnlockBits(bmpData);

}

/// <summary>

/// 得到有效圖形并調整為可平均分割的大小

/// </summary>

/// <param name="dgGrayValue">灰度背景分界值</param>

/// <param name="CharsCount">有效字符數</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++) //找有效區

{

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

{

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

if (pixelValue < dgGrayValue) //根據灰度值

{

if (posx1 > j) posx1 = j;

if (posy1 > i) posy1 = i;

if (posx2 < j) posx2 = j;

if (posy2 < i) posy2 = i;

};

};

};

// 確保能整除

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

if (Span < CharsCount)

{

int leftSpan = Span / 2; //分配到左邊的空列，如span為單數,則右邊比左邊大1

if (posx1 > leftSpan)

posx1 = posx1 - leftSpan;

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

posx2 = posx2 + Span - leftSpan;

}

//復制新圖

Rectangle cloneRect = new Rectangle(posx1, posy1, posx2 - posx1 + 1, posy2 - posy1 + 1);

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

}

/// <summary>

/// 得到有效圖形,圖形為類變量

/// </summary>

/// <param name="dgGrayValue">灰度背景分界值</param>

/// <param name="CharsCount">有效字符數</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++) //找有效區

{

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

{

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

if (pixelValue < dgGrayValue) //根據灰度值

{

if (posx1 > j) posx1 = j;

if (posy1 > i) posy1 = i;

if (posx2 < j) posx2 = j;

if (posy2 < i) posy2 = i;

};

};

};

//復制新圖

Rectangle cloneRect = new Rectangle(posx1, posy1, posx2 - posx1 + 1, posy2 - posy1 + 1);

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

}

/// <summary>

/// 得到有效圖形,圖形由外面傳入

/// </summary>

/// <param name="dgGrayValue">灰度背景分界值</param>

/// <param name="CharsCount">有效字符數</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++) //找有效區

{

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

{

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

if (pixelValue < dgGrayValue) //根據灰度值

{

if (posx1 > j) posx1 = j;

if (posy1 > i) posy1 = i;

if (posx2 < j) posx2 = j;

if (posy2 < i) posy2 = i;

};

};

};

//復制新圖

Rectangle cloneRect = new Rectangle(posx1, posy1, posx2 - posx1 + 1, posy2 - posy1 + 1);

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

}

/// <summary>

/// 平均分割圖片

/// </summary>

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

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

/// <returns>分割好的圖片數組</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++) //找有效區

{

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);//復制小塊圖

}

}

return PicArray;

}

/// <summary>

/// 返回灰度圖片的點陣描述字串，1表示灰點，0表示背景

/// </summary>

/// <param name="singlepic">灰度圖</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;

}

}

}