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What is the method to quickly convert jpg to png and resize it in Python?

PHPz

May 27, 2023 pm 01:30 PM

python

Python jpg to png and resize

A very simple small program that can directly convert all .jpg in this folder to .png format. and customize the size.

Dependencies

Need to install pillow library:

pip install pillow

Code

# -*- coding:utf-8 -*-

# file name: jpg2png.py

import os
from PIL import Image

list = os.listdir()

for i in list:
    if i != &#39;jpg2png.py&#39;:
        print(i)
        Image.open(i).convert(&#39;RGBA&#39;).resize((512, 512)).save(i[:i.find(&#39;.&#39;)] + &#39;.png&#39;)

Pay attention to the file name, and the size needs to be bracketed.

Disadvantages

Cannot go to white background

Python batch converts jpg images to png images

# Convert python image format jpg to png (batch processing, unchanged size)

import os
import PIL.Image as Image
def changeJpgToPng(srcPath, dstPath):
    # 修改图像大小
    image = Image.open(srcPath)

    # 将jpg转换为png
    png_name = str(dstPath)[0:-len(&#39;.jpg&#39;)] + &#39;.png&#39;
    # image.save(png_name)
    # print(png_name)

    # image = image.convert(&#39;RGBA&#39;)
    image = image.convert(&#39;RGB&#39;)
    image.save(png_name)
    pass
 if __name__ == &#39;__main__&#39;:
    listPath = &#39;D:/BYLW666/deeplabv3-plus-pytorch-main/VOCdevkit/VOC2007/jpg/&#39;#jpg图片
    srcPath = &#39;D:/BYLW666/deeplabv3-plus-pytorch-main/VOCdevkit/VOC2007/src/&#39;#jpg图片
    dstPath = &#39;D:/BYLW666/deeplabv3-plus-pytorch-main/VOCdevkit/VOC2007/png/&#39;#png图片
    print("开始转换...")
    filename_list = os.listdir(listPath)
    for d in filename_list:
        if d.count(&#39;.jpg&#39;) > 0:
            changeJpgToPng(srcPath + d, dstPath + d)
        pass
    print("完成了...")

二、视频转图像或图像转视频
import cv2
import os


def video2image():
    cap = cv2.VideoCapture("video/01.mp4")
    count = 1
    while True:
        success, frame = cap.read()
        if success == False:
            break
        cv2.imwrite("images/%d.jpg" % count, frame)
        count += 1


def image2video():
    # 得到图像路径
    files = os.listdir("images/")
    # 对图像排序
    files.sort(key=lambda x: int(x.split(".")[0]))
    # 获取图像宽高
    h, w, _ = cv2.imread("images/" + files[0]).shape
    # 设置帧数
    fps = 30

    vid = []
    &#39;&#39;&#39;
    设置要保存的格式
    mp4:
        mp4v 
    avi:
        xvid
        i420
    &#39;&#39;&#39;

    # 保存视频路径和名称
    # save_path = "video/video.mp4"		# 保存视频路径和名称 MP4格式
    save_path = "video/video.avi"  # 保存视频路径和名称 av格式

    # 准备写入视频
    vid = cv2.VideoWriter(save_path, cv2.VideoWriter_fourcc(*&#39;mp4v&#39;), fps, (w, h))
    # vid = cv2.VideoWriter(save_path, cv2.VideoWriter_fourcc(*&#39;xvid&#39;), fps, (w, h))
    # vid = cv2.VideoWriter(save_path, cv2.VideoWriter_fourcc(*&#39;i420&#39;), fps, (w, h))

    # 写入
    for file in files:
        img = cv2.imread("images/" + file)
        vid.write(img)


if __name__ == &#39;__main__&#39;:
    print("start...")
    video2image()
    #image2video()
    print("OK!")

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