Bug 131214 - PNG images without alpha channel appear blurry in LibreOffice
Summary: PNG images without alpha channel appear blurry in LibreOffice
Status: RESOLVED WORKSFORME
Alias: None
Product: LibreOffice
Classification: Unclassified
Component: LibreOffice (show other bugs)
Version:
(earliest affected)
6.4.1.1 rc
Hardware: x86-64 (AMD64) Linux (All)
: medium normal
Assignee: Not Assigned
URL:
Whiteboard:
Keywords:
Depends on:
Blocks:
 
Reported: 2020-03-07 23:32 UTC by jh_lobugs
Modified: 2022-05-18 09:26 UTC (History)
1 user (show)

See Also:
Crash report or crash signature:


Attachments
sample document (90.48 KB, application/vnd.oasis.opendocument.presentation)
2020-03-07 23:39 UTC, jh_lobugs
Details
PNG image with alpha channel (39.35 KB, image/png)
2020-03-07 23:40 UTC, jh_lobugs
Details
PNG image without alpha channel (36.80 KB, image/png)
2020-03-07 23:41 UTC, jh_lobugs
Details
screenshot in LO (323.71 KB, image/png)
2020-03-07 23:41 UTC, jh_lobugs
Details
screenshot in MS Office (627.25 KB, image/png)
2020-03-07 23:42 UTC, jh_lobugs
Details
exported PDF (63.93 KB, application/pdf)
2020-03-07 23:43 UTC, jh_lobugs
Details
screenshot of PDF (224.99 KB, image/png)
2020-03-07 23:43 UTC, jh_lobugs
Details

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Description jh_lobugs 2020-03-07 23:32:35 UTC
Description:
If a PNG image is inserted to a LO document after removing its alpha channel (e.g. by ImageMagick convert -alpha remove), it will appear blurrier.

This seems to be limited to displaying the document in LO only. In the exported PDF, the image is clear as expected. When the LO document is directly opened in Microsoft Office, the image is clear too. I first noticed this in Impress but Writer seems to be affected too.

Steps to Reproduce:
1. Insert a PNG image without alpha channel into a LibreOffice document.


Actual Results:
It appears blurry.

Expected Results:
It should be clear.


Reproducible: Always


User Profile Reset: Yes



Additional Info:
LibreOffice
Version: 6.4.1.1
Build ID: 40(Build:1)
CPU threads: 4; OS: Linux 5.5; UI render: default; VCL: gtk3; 
Locale: en-US (en_US.UTF-8); UI-Language: en-US
Calc: threaded
Comment 1 jh_lobugs 2020-03-07 23:39:03 UTC
Created attachment 158480 [details]
sample document
Comment 2 jh_lobugs 2020-03-07 23:40:03 UTC
Created attachment 158481 [details]
PNG image with alpha channel

produced by matplotlib
Comment 3 jh_lobugs 2020-03-07 23:41:02 UTC
Created attachment 158482 [details]
PNG image without alpha channel

produced by ImageMagick: convert image_alpha.png -alpha remove image_noalpha.png
Comment 4 jh_lobugs 2020-03-07 23:41:42 UTC
Created attachment 158483 [details]
screenshot in LO
Comment 5 jh_lobugs 2020-03-07 23:42:31 UTC
Created attachment 158484 [details]
screenshot in MS Office
Comment 6 jh_lobugs 2020-03-07 23:43:15 UTC
Created attachment 158485 [details]
exported PDF
Comment 7 jh_lobugs 2020-03-07 23:43:40 UTC
Created attachment 158486 [details]
screenshot of PDF
Comment 8 Xisco Faulí 2020-05-11 14:57:15 UTC
I can't reproduce it in

Version: 7.0.0.0.alpha1+
Build ID: 86bc13248c1d9f63b10aac304bdf0361d1dcc47f
CPU threads: 4; OS: Linux 4.19; UI render: default; VCL: gtk3; 
Locale: en-US (en_US.UTF-8); UI: en-US
Calc: threaded

or at least I can't see any difference.
Could you please try to reproduce it with a master build from http://dev-builds.libreoffice.org/daily/master/ ?
You can install it alongside the standard version.
I have set the bug's status to 'NEEDINFO'. Please change it back to 'UNCONFIRMED' if the bug is still present in the master build
Comment 9 jh_lobugs 2020-05-14 06:55:27 UTC
I can't reproduce with latest 7.0.0.0.alpha1+ build. It looks like this is fixed.
Comment 10 QA Administrators 2020-05-15 03:47:30 UTC Comment hidden (obsolete)
Comment 11 Timur 2020-06-04 21:20:15 UTC
(In reply to jh_lobugs from comment #9)
> I can't reproduce with latest 7.0.0.0.alpha1+ build. It looks like this is
> fixed.

I reproduced this before in Windows with OpenGL. Please test with and without. 
Now I don't repro with Skia.
Comment 12 QA Administrators 2020-12-08 04:25:34 UTC Comment hidden (obsolete)
Comment 13 QA Administrators 2021-01-08 04:20:32 UTC Comment hidden (obsolete)
Comment 14 Timur 2022-05-18 09:26:21 UTC
This is not INSUFFICIENTDATA but WFM as OpenGL problem is no more.