Bug 23963 - Visible reduction in image quality
Summary: Visible reduction in image quality
Status: Pushed to stable
Alias: None
Product: Koha
Classification: Unclassified
Component: Tools (show other bugs)
Version: master
Hardware: All All
: P5 - low major (vote)
Assignee: Martin Renvoize
QA Contact: Martin Renvoize
Depends on: 21987
Blocks: 22988
  Show dependency treegraph
Reported: 2019-11-04 13:24 UTC by Martin Renvoize
Modified: 2019-11-15 10:14 UTC (History)
8 users (show)

See Also:
Change sponsored?: ---
Patch complexity: ---
Who signed the patch off:
Text to go in the release notes:
Version(s) released in:


Note You need to log in before you can comment on or make changes to this bug.
Description Martin Renvoize 2019-11-04 13:24:41 UTC
+++ This bug was initially created as a clone of Bug #22988 +++

RM NOTE: This bug is a placeholder to note that we are reverting bug 21987 whilst we work on the main issue for a longer term resolution to bug 22988 in that bug.

I have a library that is noticing a visible reduction in image and thumbnail quality after upgrading from 18.11.03 to 18.11.05. This could be a regression from bug 21987. 

They have a lot of scanned black and white covers. The largest text in the thumbnails used to be readable, but after the upgrade, it is not. Their scanning process has not changed, so the original image that they upload should be of the same quality as before. 

Old, good image:

New, not so good, image:

Did we reduce the quality a bit too much?
Comment 1 Martin Renvoize 2019-11-04 13:32:26 UTC
Revert pushed to master for 19.11
Comment 2 Fridolin SOMERS 2019-11-15 10:14:27 UTC
Pushed to 19.05.x for 19.05.05