Bug 410696

Summary: No thumbnails generated for cb7 comic book archives
Product: [Frameworks and Libraries] kio-extras Reporter: G_v_I <riddervancocagne>
Component: Thumbnails and previewsAssignee: Plasma Bugs List <plasma-bugs>
Status: RESOLVED FIXED    
Severity: wishlist CC: kde, nate
Priority: NOR    
Version: 19.07.80   
Target Milestone: ---   
Platform: Kubuntu   
OS: Linux   
See Also: https://bugs.kde.org/show_bug.cgi?id=419126
Latest Commit: https://commits.kde.org/kio-extras/c4b212d7211e79acbbe74c51226a1256fa6beac0 Version Fixed In: 19.12.0
Sentry Crash Report:
Attachments: A cb7 file for testing. The images and text that it contains are out of copyright.

Description G_v_I 2019-08-07 13:44:30 UTC 
SUMMARY
The thumbnailer used by Dolphin is capable of generating thumbnails for comic book archives that were compressed using the zip and rar algorithms, generally recognisable by the file extensions cbz and cbr. It cannot, however, generate thumbnails for comic book archives which were compressed using the 7zip algorithm, generally recognisable from their cb7 file extension, although cbz is also used.

An extension is available on Opendesktop.org/KDE Store which adds the ability to create thumbnails for cb7 files, yet it only works with KDE 4. See https://store.kde.org/p/1080707/. 

STEPS TO REPRODUCE
1. Enable previews in Dolphin.
2. Browse to a folder containing cb7 files.


OBSERVED RESULT
No thumbnails are generated.

EXPECTED RESULT
Thumbnails are generated.

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
Linux/KDE Plasma: 
(available in About System)
KDE Plasma Version: 5.16.4
KDE Frameworks Version: 5.60.0
Qt Version: 5.12.2

ADDITIONAL INFORMATION
Comment 1 Nate Graham 2019-08-07 19:29:07 UTC 
Can you attach one such file for testing purposes?
Comment 2 G_v_I 2019-08-07 23:23:17 UTC 
Created attachment 122002 [details]
A cb7 file for testing. The images and text that it contains are out of copyright.
Comment 3 G_v_I 2019-08-07 23:23:58 UTC 
(In reply to Nate Graham from comment #1)
> Can you attach one such file for testing purposes?

Done!
Comment 4 Kai Uwe Broulik 2019-08-08 07:01:06 UTC 
Given this is just an archive with sequentially numbered images inside [1], writing a thumbnailer should be pretty straightforward.
Bonus points if Okular also gained support for those (Evince has).

[1] https://en.wikipedia.org/wiki/Comic_book_archive
Comment 5 Kai Uwe Broulik 2019-08-08 14:00:10 UTC 
Git commit c4b212d7211e79acbbe74c51226a1256fa6beac0 by Kai Uwe Broulik.
Committed on 08/08/2019 at 13:59.
Pushed by broulik into branch 'master'.

[Comic Thumbnailer] Add support for 7zip-compressed comic books

Differential Revision: https://phabricator.kde.org/D23022

M  +1    -1    thumbnail/comicbookthumbnail.desktop
M  +6    -0    thumbnail/comiccreator.cpp
M  +2    -1    thumbnail/comiccreator.h

https://commits.kde.org/kio-extras/c4b212d7211e79acbbe74c51226a1256fa6beac0
Comment 6 Higa 2019-08-09 02:44:39 UTC 
I have submitted D23037 which adds cb7 comic book archives support for Okular, please feel free to test the patch:  https://phabricator.kde.org/D23037