python-批量letterbox_resize图片

import numpy as np
import cv2
import os

def letterbox_resize(img, new_width, new_height, interp=0):
    '''
    Letterbox resize. keep the original aspect ratio in the resized image.
    '''
    ori_height, ori_width = img.shape[:2]

    resize_ratio = min(new_width / ori_width, new_height / ori_height)

    resize_w = int(resize_ratio * ori_width)
    resize_h = int(resize_ratio * ori_height)

    img = cv2.resize(img, (resize_w, resize_h), interpolation=interp)
    image_padded = np.full((new_height, new_width, 3), 128, np.uint8)

    dw = int((new_width - resize_w) / 2)
    dh = int((new_height - resize_h) / 2)

    image_padded[dh: resize_h + dh, dw: resize_w + dw, :] = img

    return image_padded

path = ./Annotations/" 
filelist = os.listdir(path)
filelist.sort()

for file in filelist:
    print(file)
    
count=0
for file in filelist:
    img= cv2.imread("./Annotations/"+file)
    outimg=letterbox_resize(img,1920,1080,interp=0)
    path='./VOC2007/' + str(count) + '.jpg'
    cv2.imwrite(path, outimg)
    count+=1