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 : [email protected]
    @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)