save("file.pdf") generates JPEG image in PDF container

[apparebit]

Prework

• [x] Read and agree to the code of conduct and contributing guidelines.
• [x] If there is already a relevant issue, whether open or closed, comment on the existing thread instead of posting a new issue.

Description

When generating a PDF document with GT, I end up with a PDF container wrapping a pixel-based JPEG image and not a vector-based PDF. That effectively defeats the purpose of using PDF. Furthermore, at 1:1 pixel sizing, the image compression is strong enough to produce visible artifacts that make text look slightly soft and blurry. Just to be sure, I inspected the generated PDF file with a PDF debugger.

Reproducible example

from great_tables import GT
from great_tables.data import exibble
GT(exibble).save("exibble.pdf")

• [x] Post a minimal reproducible example (MRE) so the maintainer can troubleshoot the problems you identify. A reproducible example is:
  • [x] Runnable: post enough code and data so any onlooker can create the error on their own computer.
  • [x] Minimal: reduce runtime wherever possible and remove complicated details that are irrelevant to the issue at hand.
  • [x] Readable: format your code according to the Style Guide for Python Code.

Expected result

I expect a PDF document of a textual table to contain vector-outlines not pixels.

Development environment

• Operating System: macOS
• great_tables Version: 0.18.0