File size of preview images greater than original file

[hul51u]

Describe the bug For some jpeg files with high compression rate and resolution above 4k the generated jpeg's file size (max preview with 4K resolution) is greater than the original file's size.

To Reproduce Steps to reproduce the behavior:

1. Upload a high resolution jpeg file with high compression.
2. View the max preview jpeg and get its filesize
3. Filesize in some cases is greater than orignal jpeg (although resolution is less)

Expected behavior Max Preview should not be generated and served to client.

Desktop:

• Browser: Chrome 90

Server:

• Nextcloud 21.0.2 with up to date apps