如何使用`cv2.putText`正确地在图像上绘制中文文本？(Python的+ OpenCV的)

Question

我使用python cv2(window10,python2.7)在图像中写入文本,当文本是英文时它可以工作,但是当我使用中文文本时它会在图像中写出乱码.

以下是我的代码:

# coding=utf-8
import cv2
import numpy as np

text = "Hello world"   # just work
# text = "??????"  # messy text in the image

cv2.putText(img, text,
            cord,
            font,
            fontScale,
            fontColor,
            lineType)

# Display the image
cv2.imshow("img", img)

cv2.waitKey(0)
cv2.destroyAllWindows()

当text = "Hello world" # just work下面是输出图像时:

当text = "??????" # Chinese text, draw messy text in the image下面是输出图像时:

怎么了？opencv putText不支持其他语言文本吗？

Answer 1

据cv2.putText我所知,不支持no-ascii char.Try to use PIL to draw NO-ASCII(such Chinese) on the image.

import numpy as np
from PIL import ImageFont, ImageDraw, Image
import cv2
import time

## Make canvas and set the color
img = np.zeros((200,400,3),np.uint8)
b,g,r,a = 0,255,0,0

## Use cv2.FONT_HERSHEY_XXX to write English.
text = time.strftime("%Y/%m/%d %H:%M:%S %Z", time.localtime()) 
cv2.putText(img,  text, (50,50), cv2.FONT_HERSHEY_SIMPLEX, 0.7, (b,g,r), 1, cv2.LINE_AA)


## Use simsum.ttc to write Chinese.
fontpath = "./simsun.ttc" # <== ??????? 
font = ImageFont.truetype(fontpath, 32)
img_pil = Image.fromarray(img)
draw = ImageDraw.Draw(img_pil)
draw.text((50, 80),  "??????????", font = font, fill = (b, g, r, a))
img = np.array(img_pil)

cv2.putText(img,  "--- by Silencer", (200,150), cv2.FONT_HERSHEY_SIMPLEX, 0.5, (b,g,r), 1, cv2.LINE_AA)


## Display 
cv2.imshow("res", img);cv2.waitKey();cv2.destroyAllWindows()
#cv2.imwrite("res.png", img)

请参阅我的另一个答案:

将TrueType字体加载到OpenCV

Answer 2

根据这个opencv论坛，putText只能支持一小部分ascii字符子集，不支持unicode字符，即其他符号，例如中文和阿拉伯字符。

但是，您可以尝试使用 PIL 代替，并按照此处发布的答案进行操作，看看它是否适合您。