Python操作PDF文件之實現A3頁面轉A4

import fitz
import time
import os
import cv2
from fpdf import FPDF
from PIL import Image


# 將pdf分割為圖片，並建立一個images1文件夾保存之 傳入要拆解的pdf文件名
def to_image(file_name):
    dir1 = "images1"
    if not os.path.exists(dir1):
        os.mkdir(dir1)
    time_start = time.time()
    doc = fitz.open(file_name)
    rotate = int(0)
    zoom_x = 2.0
    zoom_y = 2.0
    trans = fitz.Matrix(zoom_x, zoom_y)
    print("%s開始轉換..." % file_name)

    pg = 0
    for page in doc:
        timep_start = time.time()
        pg += 1
        pm = page.get_pixmap(matrix=trans, alpha=False)
        new_full_name = dir1 + "/" + file_name.split(".")[0]
        filename1 = "{0:s}{1:0>3d}.jpg".format(new_full_name, pg)
        pm.save(filename1)
        timep_end = time.time()
        print('第 ' + str(pg) + ' 頁生成圖片累計用時：' + str(timep_end - timep_start))

    time_end = time.time()
    print('拆解累計用時：' + str(time_end - time_start))


# 將images1文件夾中的每個圖片，左右分割為兩張，並新建images2文件夾以保存文件
def cut_img():
    for img in os.listdir("images1"):
        image = cv2.imread("images1/" + img)
        x0 = int(image.shape[1]/2)
        dir2 = "images2"
        if not os.path.exists(dir2):
            os.mkdir(dir2)
        img1 = image[:, 0:x0]
        img2 = image[:, x0:]
        cv2.imwrite(dir2 + "/" + img[:-4] + '1.jpg', img1)
        cv2.imwrite(dir2 + "/" + img[:-4] + '2.jpg', img2)


# 將images2文件夾中的圖片合並成為一個pdf，按照文件名的順序 傳入輸出的pdf文件名
def makePdf(pdfFileName):
    listPages = ["images2/" + imgFileName for imgFileName in os.listdir('images2')]
    cover = Image.open(listPages[0])
    width, height = cover.size
    pdf = FPDF(unit="pt", format = [width, height])
    for page in listPages:
        pdf.add_page()
        pdf.image(page, 0, 0)
    pdf.output(pdfFileName, "F")


# 執行
if __name__ == "__main__":
    to_image("test.pdf")
    cut_img()
    makePdf("result.pdf")