2020-08-21

标题

图片裁剪

import cv2
 
img = cv2.imread("./data/cut/thor.jpg")
print(img.shape)
cropped = img[0:128, 0:512]  # 裁剪坐标为[x0:x1, y0:y1]
cv2.imwrite("./data/cut/cv_cut_thor.jpg", cropped) # 保存到本地相对位置

模板匹配

    src=cv.imread("C:\images\cv_cut_thor.jpg")#coins.jpg
    cv.imshow("image",src)
    dst=cv.GaussianBlur(src,(3,3),0)#高斯滤波
    gray=cv.cvtColor(dst,cv.COLOR_BGR2GRAY)#转换为灰度图
    #使用二值化
    #ret,binary=cv.threshold(gray,0,255,cv.THRESH_BINARY|cv.THRESH_OTSU)
    #cv.imshow("binary image",binary)
    #使用Canny
    edge_output=cv.Canny(gray,30,90)
    cv.imshow("Canny image",edge_output)
    cv.imwrite("C:\images\MobanCanny.jpg", edge_output)
    #寻找轮廓
    contours, heriachy = cv.findContours(edge_output, cv.RETR_EXTERNAL, cv.CHAIN_APPROX_SIMPLE)
    for i, contour in enumerate(contours):
        cv.drawContours(src, contours, i, (0, 255, 0), 1)#画轮廓 线宽2
        print(i)
    cv.imshow("detect contours", src)