background

In certain environments, drawing vector PDFs sometimes did not work. To avoid this problem, I want to convert and save as a rasterized PDF such as JPEG instead of vector.

Method

It was easily realized using Python3.

Advance preparation

Installing Pillow
Install pdf2image

code

`main.py`


import pdf2image as p
from PIL import Image
import sys

#Rasterized resolution
#The larger the value, the more beautiful it is, but it takes time (the beauty is better at a certain value)
DPI = 300

#Image height of final output PDF
HEIGHT = 1200

pdfpath = sys.argv[1]
images = p.convert_from_path(pdfpath, dpi=DPI)

def resize(image):
    r = HEIGHT / image.height
    width = int(image.width * r)
    return image.resize((width, HEIGHT), Image.LANCZOS)

images = list(map(resize, images))
images = list(map(lambda image: image.convert('RGB'), images))

images[0].save('output.pdf',save_all=True, append_images=images[1:])

Rasterize to a higher resolution first, and then reduce to the image with the desired resolution to improve the image quality.

How to use

Suppose the PDF file you want to convert (hoge.pdf) is in the execution folder.

$ python main.py hoge.pdf

When the above command is executed, ʻoutput.pdf` will be generated in the executed directory.

Complete

Rasterize PDF in Python