内镜去黑边

对内境图片裁剪，去除黑边，效果如下图所示

原图

标出矩形框

结果

import cv2
import os

def main01():
    root = "C:\\Users\\liuminggui\\Desktop\\rename\\all\\"  # 图片来源路径
    save_path = "C:\\Users\\liuminggui\\Desktop\\rename\\save\\"  # 图片修改后的保存路径
    images = os.listdir(root)
    for i in images:
        path = root + i
        print(i)
        x,y,w,h=rect_crop(path) # 得到要裁剪的，左上角坐标(x,y)和宽度w,高度h

        image=cv2.imread(root+i)
        cv2.imwrite(save_path+i, image[y:y+h+1,x:x+w+1])  # 保存裁剪图片

def rect_crop(root=r'F:\Project\DenseBox\data\000001.jpg'):
    img = cv2.imread(root)
    # img = cv2.pyrDown(img)
    gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)  # 得到灰度图
    x_,y_ = gray.shape
    ret,thresh = cv2.threshold(gray,50,255,cv2.THRESH_BINARY)   # 测试得到50比较好
    # 注意opencv2和3这个函数可能有2个或者三个返回值
    img111,contours,hier = cv2.findContours(thresh,cv2.RETR_EXTERNAL,cv2.CHAIN_APPROX_SIMPLE)

    for c in contours:  # 遍历所有轮廓
        print(c)
        x,y,w,h = cv2.boundingRect(c)
        if w * h > x_ * y_ * 0.33:  # 轮廓大于整个面积的1/3，应该就是我们要找的
            cv2.rectangle(img,(x,y),(x+w,y+h),(0,255,0),2)
            print(x,y,w,h)
            cv2.imshow('img+rectangle',img)
            cv2.imshow('thresh', thresh)
            cv2.waitKey(0)
            return (x,y,w,h)
    return (0,0,0,0)  # 找不到大矩形轮廓，则返回默认值0



if __name__ == '__main__':
    # main1()
    # liuminggui()
    main01()

cover from YSH and sloan