Python OpenCV cv2.copyMakeBorder()用法及代码示例

OpenCV-Python是旨在解决计算机视觉问题的Python绑定库。cv2.copyMakeBorder()方法用于在像相框一样的图像周围创建边框。

用法： cv2.copyMakeBorder(src, top, bottom, left, right, borderType, value)

参数：
src:它是源图像。
top:它是顶部方向上的像素数的边框宽度。
bottom:它是底部方向上的像素数的边框宽度。
left:它是左侧像素的边界宽度。
right:它是沿正确方向的像素数的边框宽度。
borderType:它描述了要添加哪种边框。它由cv2.BORDER_CONSTANT，cv2.BORDER_REFLECT等标志定义
value:这是一个可选参数，如果border type为，则描述边框的颜色cv2.BORDER_CONSTANT。

返回值：它返回一个图像。

borderType标志如下所述：

cv2.BORDER_CONSTANT: It adds a constant colored border. The value should be given as next argument.
cv2.BORDER_REFLECT: The border will be mirror reflection of the border elements. Suppose, if image contains letters “abcdefg” then output will be “gfedcba|abcdefg|gfedcba“.
cv2.BORDER_REFLECT_101 or cv2.BORDER_DEFAULT: It does the same works as cv2.BORDER_REFLECT but with slight change. Suppose, if image contains letters “abcdefgh” then output will be “gfedcb|abcdefgh|gfedcba“.
cv2.BORDER_REPLICATE: It replicates the last element. Suppose, if image contains letters “abcdefgh” then output will be “aaaaa|abcdefgh|hhhhh“.

用于以下所有示例的图像：

示例1:

# Python program to explain cv2.copyMakeBorder() method  
   
# importing cv2  
import cv2  
   
# path  
path = r'C:\Users\Rajnish\Desktop\geeksforgeeks\geeks.png'
   
# Reading an image in default mode 
image = cv2.imread(path) 
   
# Window name in which image is displayed 
window_name = 'Image'
  
# Using cv2.copyMakeBorder() method 
image = cv2.copyMakeBorder(image, 10, 10, 10, 10, cv2.BORDER_CONSTANT) 
  
# Displaying the image  
cv2.imshow(window_name, image)

输出：

示例2:

# Python program to explain cv2.copyMakeBorder() method  
   
# importing cv2  
import cv2  
   
# path  
path = r'C:\Users\Rajnish\Desktop\geeksforgeeks\geeks.png'
   
# Reading an image in default mode 
image = cv2.imread(path) 
   
# Window name in which image is displayed 
window_name = 'Image'
  
# Using cv2.copyMakeBorder() method 
image = cv2.copyMakeBorder(image, 100, 100, 50, 50, cv2.BORDER_REFLECT) 
  
# Displaying the image  
cv2.imshow(window_name, image)

输出：

相关用法

注：本文由纯净天空筛选整理自Rajnis09大神的英文原创作品 Python OpenCV | cv2.copyMakeBorder() method。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。