识别指定window窗口的文本

1. 简单需求

通过图文识别读取一个指定window窗口的文本。 获取窗口句柄，截图保存成bitmap ,调用图文识别库.

测试结果是对中文下的识别不是特别好。

需要注意的是，tessdata要下载指定目录页下。

2. 引用包

a. 引用 tesseract4.1  b.  Emgu.CV组件

3. 上代码

using System; using System.Drawing; using System.Drawing.Imaging; using System.Runtime.InteropServices; using Emgu.CV; using Emgu.CV.OCR; using Emgu.CV.Structure; using Tesseract; using System.Windows.Forms; using Pix = Tesseract.Pix; using PageSegMode = Tesseract.PageSegMode;  public class Program {     [DllImport("user32.dll", SetLastError = true)]     public static extern IntPtr FindWindow(string lpClassName, string lpWindowName);      [DllImport("user32.dll")]     public static extern IntPtr GetWindowDC(IntPtr hWnd);      [DllImport("user32.dll")]     public static extern bool ReleaseDC(IntPtr hWnd, IntPtr hDC);      [DllImport("gdi32.dll")]     public static extern uint GetPixel(IntPtr hdc, int nXPos, int nYPos);      [DllImport("user32.dll", SetLastError = true)]     public static extern bool GetWindowRect(IntPtr hwnd, out RECT lpRect);       [DllImport("user32.dll")]     public static extern bool SetForegroundWindow(IntPtr hWnd);      [StructLayout(LayoutKind.Sequential)]     public struct RECT     {         public int Left;         public int Top;         public int Right;         public int Bottom;     }       [DllImport("user32.dll", CharSet = CharSet.Auto, ExactSpelling = true, CallingConvention = CallingConvention.Winapi)]     public static extern void keybd_event(byte bVk, byte bScan, uint dwFlags, int dwExtraInfo);      private const int KEYEVENTF_EXTENDEDKEY = 0x0001;     private const int KEYEVENTF_KEYUP = 0x0002;      private const int VK_MENU = 0x12; // Alt     private const int VK_S = 0x53; // S key       public static Bitmap CaptureWindow(IntPtr hWnd)     {         RECT rect;         GetWindowRect(hWnd, out rect);          Bitmap bmp = new Bitmap(rect.Right - rect.Left, rect.Bottom - rect.Top, PixelFormat.Format32bppArgb);         Graphics g = Graphics.FromImage(bmp);         g.CopyFromScreen(rect.Left, rect.Top, 0, 0, bmp.Size, CopyPixelOperation.SourceCopy);          return bmp;     }      public static void Main()     {         string windowTitle = "*无标题 - 记事本";          //*无标题 - 记事本         IntPtr hWnd = FindWindow(null, windowTitle);          if (hWnd == IntPtr.Zero)         {             Console.WriteLine($"Could not find window with title '{windowTitle}'");             return;         }          SetForegroundWindow(hWnd);         //SendKeys.SendWait("%(s)"); //发送Alt+S事件           // Press Alt + S         //keybd_event(VK_MENU, 0x45, KEYEVENTF_EXTENDEDKEY | 0, 0);         //keybd_event(VK_S, 0x45, KEYEVENTF_EXTENDEDKEY | 0, 0);          //// Release Alt + S         //keybd_event(VK_S, 0x45, KEYEVENTF_EXTENDEDKEY | KEYEVENTF_KEYUP, 0);         //keybd_event(VK_MENU, 0x45, KEYEVENTF_EXTENDEDKEY | KEYEVENTF_KEYUP, 0);             //图文识别         Bitmap bmp = CaptureWindow(hWnd);          //tessdata/tessdata-4.1.0         TesseractEngine engine = new TesseractEngine(@"./tessdata", "eng", EngineMode.TesseractAndLstm);          using (Bitmap bmpImage = new Bitmap(bmp))         {             byte[] imageData = ImageToByte(bmpImage);             using (var image = Pix.LoadFromMemory(imageData))             {                 using (var page = engine.Process(image))                 {                     var text = page.GetText();                     Console.WriteLine("Text recognized from image: {0}", text);                 }             }         }      }      private static byte[] ImageToByte(Bitmap img)     {         ImageConverter converter = new ImageConverter();         return (byte[])converter.ConvertTo(img, typeof(byte[]));     } }

 上述代码使用的是net6.0 开发的。控制台程序模拟windows事件，尤其是键盘快捷键时，有点问题。暂未处理。

就这样吧，兴趣所致，就是玩玩。 天太冷了，不想写的太多。 纯粹凑字数。