python编程快速上手之第17章实践项目参考答案(17.7.1)

#! python3
# resizeAndAddLogo.py - Resizes all images in current working directory to fit
# in a 300x300 square, and adds catlogo.png to the lower-right corner.

import os
from PIL import Image

os.chdir('C:\\Users\\Administrator\\Python35-32\\test\\kuaisu\\科幻')#设置文件路径
SQUARE_FIT_SIZE = 500 #设置图片修改大小
LOGO_SIZE=80     #设置LOGO大小，原图有800像素，太大了，设为80
LOGO_FILENAME = 'catlogo.png'

logoIm = Image.open(LOGO_FILENAME)
logoIm = logoIm.resize((LOGO_SIZE, LOGO_SIZE))
logoWidth, logoHeight = logoIm.size

os.makedirs('withLogo', exist_ok=True)
# Loop over all files in the working directory.
for filename in os.listdir('.'):
    if not (filename.endswith('.png') or filename.endswith('.jpg') \
            or filename.endswith('.PNG') or filename.endswith('.JPG')) \
       or filename == LOGO_FILENAME:
        continue # skip non-image files and the logo file itself
    
    im = Image.open(filename)
    im = im.convert('RGB')
    width, height = im.size

    # Check if image needs to be resized.
    if width > SQUARE_FIT_SIZE and height > SQUARE_FIT_SIZE:
        # Calculate the new width and height to resize to.
        if width > height:
            height = int((SQUARE_FIT_SIZE / width) * height)
            width = SQUARE_FIT_SIZE
        else:
            width = int((SQUARE_FIT_SIZE / height) * width)
            height = SQUARE_FIT_SIZE

        # Resize the image.
        print('Resizing %s...' % (filename))
        im = im.resize((width, height))

    # Add logo.
    if min(width, height) >= 2*int(LOGO_SIZE):       
      print('Adding logo to %s...' % (filename))
      im.paste(logoIm, (width - logoWidth, height - logoHeight),logoIm)

    # Save changes.
      im.save(os.path.join('withLogo', filename))