跟着我们一起学 Python 30天课程-第21天-脚本编写基础

import os
from PIL import Image

# fetch all the files from the source folder
dirname = 'images'
output_dirname = 'generated'
images_list = os.listdir(dirname)

# check if output folder exits otherwise create it
if not os.path.exists(output_dirname):
    os.makedirs(output_dirname)

for image in images_list:
    # split the filename to separate the format and name
    name, format = os.path.splitext(image)

    original = Image.open(f'{dirname}\{image}')

    # resize image to a standard size and to reduce file size
    size = 1000,1000
    # thumbnail maintains aspect ratio
    original.thumbnail(size) 


    # save image as png format
    original.save(f'{output_dirname}\{name}.png')

import os
from PIL import Image, ImageFilter

# fetch all the files from the source folder
dirname = 'images'
output_dirname = 'greyscale'
images_list = os.listdir(dirname)

# check if output folder exits otherwise create it
if not os.path.exists(output_dirname):
    os.makedirs(output_dirname)

for image in images_list:
    # split the filename to separate the format and name
    name, format = os.path.splitext(image)

    original = Image.open(f'{dirname}\{image}')

    # resize image to a standard size and to reduce file size
    size = 1000, 1000
    # thumbnail maintains aspect ratio
    original.thumbnail(size)

    # convert the image to greyscale
    grayscale_image = original.convert('L')  # L mode means greyscale
    grayscale_image.save(f'{output_dirname}\{image}')

import os
from PIL import Image, ImageFilter

# fetch all the files from the source folder
dirname = 'images'
output_dirname = 'branded'
images_list = os.listdir(dirname)
logo = Image.open('logo.png')

# check if output folder exits otherwise create it
if not os.path.exists(output_dirname):
    os.makedirs(output_dirname)

for image in images_list:
    # split the filename to separate the format and name
    name, format = os.path.splitext(image)

    original = Image.open(f'{dirname}\{image}')

    # resize image to a standard size and to reduce file size
    size = 1000, 1000
    # thumbnail maintains aspect ratio
    original.thumbnail(size)

    # create a copy of the image
    image_copy = original.copy()
    # obtain the position to place the logo

    position = ((image_copy.width - logo.width),
                (image_copy.height - logo.height))
    # The third parameter makes it transparent
    image_copy.paste(logo, position, logo)
    image_copy.save(f'{output_dirname}\{name}.png')

from PyPDF2 import PdfFileReader

def extract_information(pdf_path):
    with open(pdf_path, 'rb') as f:
        pdf = PdfFileReader(f)
        information = pdf.getDocumentInfo()
        number_of_pages = pdf.getNumPages()

    txt = f"""
    Information about {pdf_path}: 

    Author: {information.author}
    Creator: {information.creator}
    Producer: {information.producer}
    Subject: {information.subject}
    Title: {information.title}
    Number of pages: {number_of_pages}
    """

    print(txt)
    return information

if __name__ == '__main__':
    path = 'pdfs/sample1.pdf'
    extract_information(path)

from PyPDF2 import PdfFileWriter, PdfFileReader

def create_watermark(input_pdf, output, watermark):
    watermark_obj = PdfFileReader(watermark)
    watermark_page = watermark_obj.getPage(0)

    pdf_reader = PdfFileReader(input_pdf)
    pdf_writer = PdfFileWriter()

    # Watermark all the pages
    for page in range(pdf_reader.getNumPages()):
        page = pdf_reader.getPage(page)
        page.mergePage(watermark_page)
        pdf_writer.addPage(page)

    with open(output, 'wb') as out:
        pdf_writer.write(out)

if __name__ == '__main__':
    create_watermark(
        input_pdf='pdfs/sample1.pdf', 
        output='pdfs/watermarked_sample.pdf',
        watermark='pdfs/watermark.pdf')