python图片格式转换脚本

目录

• 前言
• 1.cv2
• 1.1 导包
• 1.2 路径设置
• 1.3 改格式重新传
• 1.4 查看结果
• 2.pillow
• 2.1 导包
• 2.2 路径设置
• 2.3 写格式修改函数
• 2.4 开始转换
• 2.5 查看结果

前言

常见的图像任务通常需要把照片统一成相同的格式，所以此文章正是为了统一格式而生，常见的主要有cv2和PIL.Image的相关操作，照片格式是一串数字加上后缀名

1.cv2

pip install opencv-python之后就可以import cv2

1.1 导包

import os
import cv2
import sys
import numpy as np

1.2 路径设置

path = r\"C:\\\\Users\\\\86775\\\\PycharmProjects\\\\pythonProject2\\\\ResNet\\\\test_change\\\\\"
path2 = r\"C:\\\\Users\\\\86775\\\\PycharmProjects\\\\pythonProject2\\\\ResNet\\\\test_change2\\\\\"

1.3 改格式重新传

1.3.1 用os.path.splitext()来判断

images = os.listdir(path)
for i in os.listdir(path):
    print(os.path.splitext(i))  # (\'34474006827920603\', \'.png\')
    if os.path.splitext(i)[1] == \".jpeg\":
        img = cv2.imread(path + i)
        # print(img)
        new_imagename = i.replace(\".jpeg\", \".jpg\")
        cv2.imwrite(path2 + new_imagename, img)

    elif os.path.splitext(i)[1] == \".png\":
        img = cv2.imread(path + i)
        # print(img)
        new_imagename = i.replace(\".png\", \".jpg\")
        cv2.imwrite(path2 + new_imagename, img)

    elif os.path.splitext(i)[1] == \".JPG\":
        img = cv2.imread(path + i)
        # print(img)
        new_imagename = i.replace(\".JPG\", \".jpg\")
        cv2.imwrite(path2 + new_imagename, img)

    elif os.path.splitext(i)[1] == \".PNG\":
        img = cv2.imread(path + i)
        # print(img)
        new_imagename = i.replace(\".PNG\", \".jpg\")
        cv2.imwrite(path2 + new_imagename, img)

    elif os.path.splitext(i)[1] == \".jpg\":
        img = cv2.imread(path + i)
        # print(img)
        cv2.imwrite(path2 + i, img)

1.3.2 用split()来判断

images = os.listdir(path)
for i in os.listdir(path):
    print(i.split(\".\"))
    if i.split(\".\")[1] == \"jpeg\":
        img = cv2.imread(path + i)
        # print(img)
        new_imagename = i.replace(\".jpeg\", \".jpg\")
        cv2.imwrite(path2 + new_imagename, img)

    elif i.split(\".\")[1] == \"png\":
        img = cv2.imread(path + i)
        # print(img)
        new_imagename = i.replace(\".png\", \".jpg\")
        cv2.imwrite(path2 + new_imagename, img)

    elif i.split(\".\")[1] == \"JPG\":
        img = cv2.imread(path + i)
        # print(img)
        new_imagename = i.replace(\".JPG\", \".jpg\")
        cv2.imwrite(path2 + new_imagename, img)

    elif i.split(\".\")[1] == \"PNG\":
        img = cv2.imread(path + i)
        # print(img)
        new_imagename = i.replace(\".PNG\", \".jpg\")
        cv2.imwrite(path2 + new_imagename, img)

    elif i.split(\".\")[1] == \"jpg\":
        img = cv2.imread(path + i)
        # print(img)
        cv2.imwrite(path2 + i, img)

1.4 查看结果

2.pillow

pip install pillow之后就可以from PIL import Image

2.1 导包

import os
from PIL import Image

2.2 路径设置

path1 = r\"C:\\\\Users\\\\86775\\\\PycharmProjects\\\\pythonProject2\\\\ResNet\\\\test_change\\\\\"
path2 = r\"C:\\\\Users\\\\86775\\\\PycharmProjects\\\\pythonProject2\\\\ResNet\\\\test_change2\\\\\"

2.3 写格式修改函数

RGBA意思是红色，绿色，蓝色，Alpha的色彩空间，Alpha指透明度，而JPG不支持透明度。
所以其他格式不转jpg可以直接保存为.png格式，转jpg就需要丢弃Alpha
img = img.convert(“RGB”)，转换成RGB，保证和jpg格式的通道数相同，也算一种图片类型变换的防报错机制

def jpeg2jpg(path_in, path_out):
    img = Image.open(path_in)
    img = img.convert(\"RGB\")
    img.save(path_out, \"JPEG\", quality=80, optimize=True, progressive=True)


def png2jpg(path_in, path_out):
    img = Image.open(path_in)
    img = img.convert(\"RGB\")
    img.save(path_out, \"JPEG\", quality=80, optimize=True, progressive=True)


def JPG2jpg(path_in, path_out):
    img = Image.open(path_in)
    img = img.convert(\"RGB\")
    img.save(path_out, \"JPEG\", quality=80, optimize=True, progressive=True)


def PNG2jpg(path_in, path_out):
    img = Image.open(path_in)
    img = img.convert(\"RGB\")
    img.save(path_out, \"JPEG\", quality=80, optimize=True, progressive=True)


def jpg2jpg(path_in, path_out):
    img = Image.open(path_in)
    img = img.convert(\"RGB\")
    img.save(path_out, \"JPEG\", quality=80, optimize=True, progressive=True)

2.4 开始转换

images = os.listdir(path1)
for i in images:
    print(i)
    if os.path.splitext(i)[1] == \".jpeg\":
        source = path1 + \"\\\\\" + str(i.split(\".\")[0]) + \".jpeg\"
        target = path2 + \"\\\\\" + str(i.split(\".\")[0]) + \".jpg\"
        jpeg2jpg(source, target)
    elif os.path.splitext(i)[1] == \".png\":
        source = path1 + \"\\\\\" + str(i.split(\".\")[0]) + \".png\"
        target = path2 + \"\\\\\" + str(i.split(\".\")[0]) + \".jpg\"
        png2jpg(source, target)
    elif os.path.splitext(i)[1] == \".JPG\":
        source = path1 + \"\\\\\" + str(i.split(\".\")[0]) + \".JPG\"
        target = path2 + \"\\\\\" + str(i.split(\".\")[0]) + \".jpg\"
        JPG2jpg(source, target)
    elif os.path.splitext(i)[1] == \".PNG\":
        source = path1 + \"\\\\\" + str(i.split(\".\")[0]) + \".PNG\"
        target = path2 + \"\\\\\" + str(i.split(\".\")[0]) + \".jpg\"
        PNG2jpg(source, target)
    elif os.path.splitext(i)[1] == \".jpg\":
        source = path1 + \"\\\\\" + str(i.split(\".\")[0]) + \".jpg\"
        target = path2 + \"\\\\\" + str(i.split(\".\")[0]) + \".jpg\"
        jpg2jpg(source, target)

2.5 查看结果