Image background removal using OpenCV
In the field of image processing, it is often necessary to separate an object from the original image, and background removal is a basic method to achieve this goal. This article will introduce how to use the GrabCut algorithm in the OpenCV library to remove the image background, and provide the corresponding Python code.
The GrabCut algorithm is an interactive foreground extraction algorithm based on graph theory, which can automatically segment the target area according to the foreground and background areas given by the user. The advantage of this algorithm is that it can make full use of human intelligence to understand the image, and at the same time it can automatically adapt to the characteristics of the image, so it has a wide range of use value in practical applications.
We first need to import the OpenCV library and read the image file to be processed. Here we use a sample image called "input.jpg", you can replace it with other images as needed.
import cv2
# 读取图像文件
img = cv2.imread('input.jpg')
Next, we need to define the marked regions for the foreground and background. In this case, we can define these areas interactively with the mouse. Specifically, the user can use the left mouse button to draw the foreground area, the right mouse button to draw the background area, and then press the "Esc" key to exit the interactive mode. In order to achieve this functionality, we need to define a callback function.