[Python知识库]使用python实现将扣好的图重叠到背景图片上

之前把两张图片重叠起来做成头像，但是没有买PS软件，用windows自带的画图软件处理无背景图片会bug，网上找到的代码又不能达到我想要的效果，就自己写了一个

希望把这两张图片重叠起来：

我的代码如下：

import cv2
import numpy as np

def img_overlap(back,front,x_bais,y_bais,zoom):
    back = np.array(back)
    taget_shape = (int(back.shape[1]*zoom),int(back.shape[0]*zoom))
    front = cv2.resize(front,taget_shape)
    front = np.array(front)
    front = front[int((front.shape[0]-back.shape[0])/2):int((front.shape[0]-back.shape[0])/2+back.shape[0]),
            int((front.shape[1]-back.shape[1])/2):int((front.shape[1]-back.shape[1])/2+back.shape[1]),:]
    front2 = np.array(front)
    for a in range(front2.shape[0]):
        for b in range(front2.shape[1]):
            for c in range(front2.shape[2]):
                if front2[a][b][c] == 0:
                    front2[a][b][c] = 1
                else:
                    front2[a][b][c] = 0
	back[max(0,y_bais):min(back.shape[0],back.shape[0]+y_bais),max(0,x_bais):min(back.shape[1],back.shape[1]+x_bais),:] *= front2[max(0,-y_bais):min(back.shape[0],back.shape[0]-y_bais),
                                                         max(0,-x_bais):min(back.shape[1],back.shape[1]-x_bais),:]
    back[max(0,y_bais):min(back.shape[0],back.shape[0]+y_bais),max(0,x_bais):min(back.shape[1],back.shape[1]+x_bais),:] += front[max(0,-y_bais):min(back.shape[0],back.shape[0]-y_bais),
                                                           max(0,-x_bais) : min(back.shape[1],back.shape[1]-x_bais), :]
    return back


if __name__ == '__main__':
    back = cv2.imread('lgd.png')   #背景图片
    front = cv2.imread('tx.png')    #重叠图片
    x_bais = 0   #横向偏移量
    y_bais = 0  #纵向偏移量
    zoom = 1    #front图片放大倍数，需大于1
    result = img_overlap(back, front, x_bais, y_bais, zoom)
    cv2.imshow('result',result)
    cv2.waitKey(0)
    cv2.imwrite('result.png',result)    #保存图片

可以设置重叠图片在横向、纵向的偏移量已经重叠图片的放大倍数（此处只能放，没有写缩小，需要缩小可以手动在画图里拉大画布），此处我的背景图片和重叠图片的尺寸分别是300x300和1080x1080，设置初始参数得到的图片如下

为了达到目标效果，将y_bias设置为38，zoom设置为1.13即可得到目标图像