OpenCV 输出文本

PutText() 输出文本

• OpenCV5 将支持中文字符的输出, 当前版本OpenCV4原生不支持, 可以使用Contrib包+FreeType方式实现, 不过比较麻烦.
• 为了省事, 也可以通过将Mat转成bitmap,然后使用GDI方式输出中文字符.

示例代码

/// <summary>/// OpenCV暂时不能支持中文字符输出,显示为??/// </summary>private void putTextTest(){string pngFile = @"D:\my_workspace\opencv\images\draw.png";var mat = Cv2.ImRead(pngFile, ImreadModes.Color);double fontScale = 1;int thinkness = 2;mat.PutText("Learn opencv中文", new OpenCvSharp.Point(100, 100), HersheyFonts.HersheyComplex,fontScale, Scalar.Red, thinkness, LineTypes.AntiAlias, false);fontScale = 2;mat.PutText("Learn opencv中文", new OpenCvSharp.Point(100, 150), HersheyFonts.HersheyComplex,fontScale, Scalar.Red, thinkness, LineTypes.AntiAlias, false);Cv2.ImShow("Learn opencv", mat);Cv2.WaitKey();}/// <summary>/// 使用GDI方式输出中文字符/// </summary>private void putChineseTest(){string pngFile = @"D:\my_workspace\opencv\images\draw.png";var mat = Cv2.ImRead(pngFile, ImreadModes.Color);var bmp = OpenCvSharp.Extensions.BitmapConverter.ToBitmap(mat);Graphics graphics = Graphics.FromImage(bmp);graphics.DrawString("Learn opencv中文", new Font("宋体", 20), new SolidBrush(Color.Red), 100, 200);var mat2 = OpenCvSharp.Extensions.BitmapConverter.ToMat(bmp);Cv2.ImShow("Learn opencv中文", mat2);Cv2.WaitKey();}

程序效果截图:

参考

• windows下编译OpenCV带opencv_contrib和freetype https://blog.csdn.net/Jay_Xio/article/details/115724624
• 听说putText()支持中文了？！ https://zhuanlan.zhihu.com/p/615815756