Bug 439595

Summary:	Replacing Epub backends to mupdf
Product:	[Applications] okular	Reporter:	Nowshed H. Imran <now.im.627>
Component:	EPub backend	Assignee:	Okular developers <okular-devel>
Status:	REPORTED ---
Severity:	wishlist	CC:	alexander.galato, beavailable, davidkacerek, jon, kde.shieling, kde, luna, nate
Priority:	NOR
Version:	21.04.2
Target Milestone:	---
Platform:	Arch Linux
OS:	Linux
Latest Commit:		Version Fixed In:
Attachments:	Rendered by Okular Rendered by Mupdf

Description Nowshed H. Imran 2021-07-07 11:47:46 UTC

Created attachment 139919 [details]
Rendered by Okular

SUMMARY
The Ebook rendering of Okular is very bad(Specially Diagrams). If I am not wrong, it uses ebook-tools which has not been updated since 2010. Mupdf does this accurately, and it can be used to render Ebook files in Okular.

Ebook File
Used a very popular book called "Python for Everybody".

https://www.py4e.com/book

Comment 1 Nowshed H. Imran 2021-07-07 11:49:06 UTC

Created attachment 139920 [details]
Rendered by Mupdf

Comment 2 Nowshed H. Imran 2021-09-06 14:28:33 UTC

Not ideal.
But another possible backend.

https://github.com/futurepress/epub.js/

Comment 3 Nowshed H. Imran 2021-09-06 14:44:49 UTC

Python Backend:
https://github.com/aerkalov/ebooklib

Comment 4 Nowshed H. Imran 2021-09-06 15:01:24 UTC

Gnome Book backend:
https://gitlab.gnome.org/GNOME/libgepub

Comment 5 Simplissimus 2022-04-14 20:40:38 UTC

Totally agree with the other commentators. The presentation of books in EPub is horrendous, plus the function to change the background color, to cause less eye fatigue and dry eyes does not work.
I would like to add that I don't know what backend is using Calibre, but EPubs look great too. Maybe it could be another alternative to consider, and I don't know if it could be easier to include in Okular since Calibre is a QT app.

Comment 6 Sune Vuorela 2023-09-27 12:36:15 UTC

I do think that this is a bad bug report. 

The bug report should describe the problem. 

The problem is that okular misrenders certain epub files. 

The problem is not that okular does not use mupdf. 

Mupdf could be *one* solution to the problem, but there might also be others that would still solve the same.