如何使用给定的坐标和python opencv在图像中绘制点?
问题描述：
我有一张图像和一个坐标(X，Y).如何在此坐标上绘制点.我想使用Python OpenCV.
I have one image and one co-ordinate (X, Y). How to draw a point with this co-ordinate on the image. I want to use Python OpenCV.
答
我也在学习与OpenCV的Python绑定.这是一种方法:
I'm learning the Python bindings to OpenCV too. Here's one way:
#!/usr/local/bin/python3
import cv2
import numpy as np
w=40
h=20
# Make empty black image
image=np.zeros((h,w,3),np.uint8)
# Fill left half with yellow
image[:,0:int(w/2)]=(0,255,255)
# Fill right half with blue
image[:,int(w/2):w]=(255,0,0)
# Create a named colour
red = [0,0,255]
# Change one pixel
image[10,5]=red
# Save
cv2.imwrite("result.png",image)
这是结果-放大后可以看到它.
Here's the result - enlarged so you can see it.
这是非常简洁但有趣的答案:
Here's the very concise, but less fun, answer:
#!/usr/local/bin/python3
import cv2
import numpy as np
# Make empty black image
image=np.zeros((20,40,3),np.uint8)
# Make one pixel red
image[10,5]=[0,0,255]
# Save
cv2.imwrite("result.png",image)