Opencv实现倾斜图片转正示例

box= cv2.minAreaRect(counter)
print(box)

# -*- coding: utf-8 -*-
# @Time : 2022/7/25 15:51
# @Author : guligedong
import cv2
import os
import numpy as np
 
base_folder = r'F:\mvtec_anomaly_detection\screw\test\good'
for i in os.listdir(base_folder):
    img_path = os.path.join(base_folder, i)
    if img_path.split('.')[-1] == 'db':
        continue
    print(img_path)
    img = cv2.imread(img_path)
    img = cv2.resize(img,(512,512))
    img_h,img_w = img.shape[:2]
    gray_img = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
    _,bi_img = cv2.threshold(gray_img,127,255,cv2.THRESH_BINARY_INV)
 
    counters,_ = cv2.findContours(bi_img,cv2.RETR_TREE,cv2.CHAIN_APPROX_SIMPLE)
    for index,counter in enumerate(counters):
        if cv2.contourArea(counter) > 10000 :
            cv2.drawContours(img,counters,index,(0,0,255),1)
            box= cv2.minAreaRect(counter)
            print(box)
            boxs= cv2.boxPoints(box)
            boxs = np.int0([boxs])
            print(boxs)
            cv2.polylines(img, boxs, isClosed=True, color=(255, 125, 125), thickness=1)
            cv2.imshow('img', img)
            # cv2.waitKey()
            center_x,center_y = int(box[0][0]),int(box[0][1])
            lenth1, lenth2 = int(box[1][0]), int(box[1][1])
            print(lenth1, lenth2)
            angle = box[2]
            print(angle)
            if lenth1 > lenth2:
                angle  = angle
            else:
                angle = -(90 - angle)
            rotate_matrix = cv2.getRotationMatrix2D(center=(center_x,center_y),angle=angle,scale=1)
            rotated_image = cv2.warpAffine(src=img, M=rotate_matrix, dsize=(img_w, img_h))
            cv2.imshow('Rotated image', rotated_image)
            y_start = center_y - min(lenth1, lenth2) // 2 if center_y - min(lenth1, lenth2) // 2 > 0 else 0
            y_end = center_y + min(lenth1, lenth2) // 2 if center_y + min(lenth1, lenth2) // 2 < img_h else img_h
            x_start = center_x - max(lenth1, lenth2) // 2 if center_x - max(lenth1, lenth2) // 2 >0 else 0
            x_end = center_x + max(lenth1, lenth2) // 2 if center_x + max(lenth1, lenth2) // 2 <img_w else img_w
            crop_image = rotated_image[y_start:y_end,x_start:x_end]
            cv2.imshow('crop_image', crop_image)
            cv2.waitKey()