OpenCV cv2.putText实现字符串换行'\n'

OpenCV cv2.putText实现字符串换行'\n'

OpenCV显示字符串时，可以调用cv2.putText直接进行显示方法，但该函数是不支持换行符"\n"的

要想实现自动换行，需要自己编程计算字符宽度，下移动宽度等操作

这里提供自己实现draw_text_line()函数，可以直接支持换行符的显示

代码实现：

  

   

    

     

    
    

     

      # -*-coding: utf-8 -*-
     
    
   

    

     

    
    

     

      """
     
    
   

    

     

    
    

     

       @Project: Demo
     
    
   

    

     

    
    

     

       @Author : panjq
     
    
   

    

     

    
    

     

       @E-mail : pan_jinquan@163.com
     
    
   

    

     

    
    

     

       @Date : 2019-12-11 19:43:34
     
    
   

    

     

    
    

     

      """
     
    
   

    

     

    
    

     

      import cv2
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      def draw_text(img, point, text, drawType="custom"):
     
    
   

    

     

    
    

     
    
      '''
     
    
   

    

     

    
    

     

       :param img:
     
    
   

    

     

    
    

     

       :param point:
     
    
   

    

     

    
    

     

       :param text:
     
    
   

    

     

    
    

     

       :param drawType: custom or custom
     
    
   

    

     

    
    

     

       :return:
     
    
   

    

     

    
    

     

       '''
     
    
   

    

     

    
    

     

          fontScale = 
      0.4
     
    
   

    

     

    
    

     

          thickness = 
      5
     
    
   

    

     

    
    

     

          text_thickness = 
      1
     
    
   

    

     

    
    

     

          bg_color = (
      255, 
      0, 
      0)
     
    
   

    

     

    
    

     

          fontFace = cv2.FONT_HERSHEY_SIMPLEX
     
    
   

    

     

    
    

     
    
      # fontFace=cv2.FONT_HERSHEY_SIMPLEX
     
    
   

    

     

    
    

     
    
      if drawType == 
      "custom":
     
    
   

    

     

    
    

     

              text_size, baseline = cv2.getTextSize(str(text), fontFace, fontScale, thickness)
     
    
   

    

     

    
    

     

              text_loc = (point[
      0], point[
      1] + text_size[
      1])
     
    
   

    

     

    
    

     

              cv2.rectangle(img, (text_loc[
      0] - 
      2 // 
      2, text_loc[
      1] - 
      2 - baseline),
     
    
   

    

     

    
    

     

                            (text_loc[
      0] + text_size[
      0], text_loc[
      1] + text_size[
      1]), bg_color, 
      -1)
     
    
   

    

     

    
    

     
        
      # draw score value
     
    
   

    

     

    
    

     

              cv2.putText(img, str(text), (text_loc[
      0], text_loc[
      1] + baseline), fontFace, fontScale,
     
    
   

    

     

    
    

     

                          (
      255, 
      255, 
      255), text_thickness, 
      8)
     
    
   

    

     

    
    

     
    
      elif drawType == 
      "simple":
     
    
   

    

     

    
    

     

              cv2.putText(img, 
      '%d' % (text), point, fontFace, 
      0.5, (
      255, 
      0, 
      0))
     
    
   

    

     

    
    

     
    
      return img
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      def draw_text_line(img, point, text_line: str, drawType="custom"):
     
    
   

    

     

    
    

     
    
      '''
     
    
   

    

     

    
    

     

       :param img:
     
    
   

    

     

    
    

     

       :param point:
     
    
   

    

     

    
    

     

       :param text:
     
    
   

    

     

    
    

     

       :param drawType: custom or custom
     
    
   

    

     

    
    

     

       :return:
     
    
   

    

     

    
    

     

       '''
     
    
   

    

     

    
    

     

          fontScale = 
      0.4
     
    
   

    

     

    
    

     

          thickness = 
      5
     
    
   

    

     

    
    

     

          fontFace = cv2.FONT_HERSHEY_SIMPLEX
     
    
   

    

     

    
    

     
    
      # fontFace=cv2.FONT_HERSHEY_SIMPLEX
     
    
   

    

     

    
    

     

          text_line = text_line.split(
      "\n")
     
    
   

    

     

    
    

     
    
      # text_size, baseline = cv2.getTextSize(str(text_line), fontFace, fontScale, thickness)
     
    
   

    

     

    
    

     

          text_size, baseline = cv2.getTextSize(str(text_line), fontFace, fontScale, thickness)
     
    
   

    

     

    
    

     
    
      for i, text 
      in enumerate(text_line):
     
    
   

    

     

    
    

     
        
      if text:
     
    
   

    

     

    
    

     

                  draw_point = [point[
      0], point[
      1] + (text_size[
      1] + 
      2 + baseline) * i]
     
    
   

    

     

    
    

     

                  img = draw_text(img, draw_point, text, drawType)
     
    
   

    

     

    
    

     
    
      return img
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      if __name__ == 
      "__main__":
     
    
   

    

     

    
    

     
    
      import copy
     
    
   

    

     

    
    

     

          image_path = 
      "./data/test/test01.jpg"
     
    
   

    

     

    
    

     

          image = cv2.imread(image_path)
     
    
   

    

     

    
    

     

          point = (
      10, 
      10)
     
    
   

    

     

    
    

     

          text_line = 
      "AAAA\nBBBB\nCCCC\n"
     
    
   

    

     

    
    

     

          image1 = draw_text(copy.copy(image), point, text_line, drawType=
      "custom")
     
    
   

    

     

    
    

     

          cv2.imshow(
      "draw_text", image1)
     
    
   

    

     

    
    

     

          image2 = draw_text_line(copy.copy(image), point, text_line)
     
    
   

    

     

    
    

     

          cv2.imshow(
      "draw_text_line", image2)
     
    
   

    

     

    
    

     

          cv2.waitKey(
      0)
     
    
   

    

     

    
    

     

          cv2.waitKey(
      0)