Bug 497209

Summary: Subtitle Editor: improvements to semi-transparent outline boxes/preview
Product: [Applications] kdenlive Reporter: Bibido <bibidiboom>
Component: Title Clips & SubtitlesAssignee: Ron <kdenlive-bugs>
Status: RESOLVED DUPLICATE    
Severity: normal CC: fritzibaby
Priority: NOR Keywords: triaged
Version First Reported In: git-master   
Target Milestone: ---   
Platform: Microsoft Windows   
OS: Microsoft Windows   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: Two-line subtitle
YouTube example for multi-line subtitle with transparent background

Description Bibido 2024-12-08 17:09:49 UTC
Created attachment 176442 [details]
Two-line subtitle

SUMMARY

Kdenlive has made some very welcome changes to its subtitling feature. What you see in the image attached to this report are my suggestions for improving it further.

STEPS TO REPRODUCE
1. Create a subtitle
2. In Subtitle Style Editor, Background choose "Box as Outline"
3. Change Outline color to black with Alpha Channel setting at 150

OBSERVED RESULT
1. When using two or more lines of text with a semi-transparent background - "Box as outline" with Alpha Channel set to a value of 150 - what happens now is the box outlines of the subtitle are not uniform, but the part where they meet gets darker as the box above overlaps the one with text below. In the image attached on the right I have highlighted the dark line in yellow on Kdenlive's monitor.
2. In the Subtitle Style Editor when I click the "Show Preview" button, I only see the first line of my subtitle even though it contains two in this case.

EXPECTED RESULT
1. Make the outline color uniform if background color of the outline is semi-transparent and don't allow boxes to overlap if there is only one subtitle with two or more lines of text.
2. Preview multiple lines of text as in the subtitle.

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
(available in the Info Center app, or by running `kinfo` in a terminal window)
Linux/KDE Plasma: 
KDE Plasma Version: 
KDE Frameworks Version: 
Qt Version: 

ADDITIONAL INFORMATION
Comment 1 Bibido 2024-12-08 17:11:04 UTC
Created attachment 176443 [details]
YouTube example for multi-line subtitle with transparent background
Comment 2 emohr 2024-12-14 17:20:33 UTC
Thank you for the feedback.
The new subtitle editor comes with version 24.12.0. 
Let’s see what else we have to adjust.
I updated the bug title a bit.
Comment 3 Ron 2025-05-21 03:47:09 UTC
Please see the comments in https://bugs.kde.org/show_bug.cgi?id=461202
about the overlapping border issue and what can/can't be done about that.

Re the separate preview issue also reported here.  In the new code that should
be landing soon there is no longer any "show preview" needed for the style
editor - changes to any style immediately propagate to clips using it in the
timeline, so you can 'preview' any clip you like just by moving the timeline cursor
to it while editing a style.  So I won't split this report and keep it open just for
that since it's already 'fixed' in my dev tree and should land in an official release
Soon.

*** This bug has been marked as a duplicate of bug 461202 ***