Bug 511128

Summary: Guide Multi-Export guide zone to end doesn't update properly
Product: [Applications] kdenlive Reporter: cromachina
Component: Rendering & ExportAssignee: Jean-Baptiste Mardelle <jb>
Status: RESOLVED FIXED    
Severity: normal CC: berndmj
Priority: NOR Keywords: triaged
Version First Reported In: 25.08.2   
Target Milestone: ---   
Platform: NixOS   
OS: Linux   
Latest Commit: https://invent.kde.org/multimedia/kdenlive/-/commit/53eeae20b7181e5a984745b5c8f561c63901a9fb Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: Guide Zone rendering dialog before
Guide Zone rendering dialog after

Description cromachina 2025-10-25 23:35:02 UTC 
SUMMARY
The calculated render time is for a Guide zone to "End" is not updated properly if the end position is changed.
If the guide flag before the end is moved around, then the render time is updated.

STEPS TO REPRODUCE
1. Add a clip to a timeline.
2. Set the zone extents to the clip size.
3. Add a Guide to the timeline, somewhere in the middle of the clip.
4. Go to Render.
5. Select Guide zone.
6. Select the From part to be the Guide that was previously created. The "End" should be selected by default.
7. Take note of the Render File Length time that is calculated.
8. Close the Render window.
9. Copy the clip in the timeline and paste it to the end of the previous clip.
10. Change the zone end by dragging it to the end of the new clip.
11. Go to Render.

OBSERVED RESULT
The render time observed in step 11 is the same as in step 7. This affects the output render time (too short, in this case).
If you also move the Guide from and back to it's original position, the render times are then updated.

EXPECTED RESULT
The render time observed in step 11 should be different (longer) than in step 7.
You shouldn't have to jiggle the Guide to coerce a time update.

SOFTWARE/OS VERSIONS
Operating System: NixOS 25.11
KDE Plasma Version: 6.4.5
KDE Frameworks Version: 6.19.0
Qt Version: 6.9.2
Kernel Version: 6.17.1-zen1 (64-bit)
Graphics Platform: X11
Processors: 24 × AMD Ryzen 9 3900X 12-Core Processor
Memory: 64 GiB of RAM (62.7 GiB usable)
Graphics Processor: AMD Radeon RX 7900 XTX
Comment 1 Bernd 2025-10-27 13:19:55 UTC 
This behavior is also present in 25.08.1 and 25.08.1 appimage on Pop!_OS
Comment 2 Jean-Baptiste Mardelle 2025-11-22 17:46:13 UTC 
Hmm, maybe I musunderstood but it looks like you mix 2 different things (maybe our UI is not clear). The render "Guide Zone" feature will render between guides. The "End" appearing in the list is the End of the project.

Resizing the timeline zone will not change the Guides rendering duration. It will only change the render duration if render is set to "Selected zone".

If I misunderstood, maybe a screenshot would help.
Comment 3 Bernd 2025-11-22 18:55:53 UTC 
Created attachment 187071 [details]
Guide Zone rendering dialog before

Following the steps from the OP
Comment 4 Bernd 2025-11-22 18:57:28 UTC 
Created attachment 187072 [details]
Guide Zone rendering dialog after

Following the steps of the OP.

Even though the timeline zone has changed, the render dialog shows the previous video length.
Comment 5 Bernd 2025-11-22 19:01:07 UTC 
(In reply to Jean-Baptiste Mardelle from comment #2)
> Resizing the timeline zone will not change the Guides rendering duration. It
> will only change the render duration if render is set to "Selected zone".

IMO, if the Guide Zone says from Beginning to End it should take the new end into consideration. Markers are clip-independent, right?
Comment 6 Jean-Baptiste Mardelle 2025-11-23 09:56:38 UTC 
Ok, understood. However as I said, the timeline zone is absolutely not related to render duration when "Marker zone" (previously named "Guide zone" is selected in the render widget.
Comment 7 Jean-Baptiste Mardelle 2025-11-23 09:58:33 UTC 
Git commit 53eeae20b7181e5a984745b5c8f561c63901a9fb by Jean-Baptiste Mardelle.
Committed on 23/11/2025 at 09:56.
Pushed by mardelle into branch 'release/25.12'.

Correctly update render duration when using marker zone rendering to the end of the project

M  +19   -5    src/dialogs/renderwidget.cpp

https://invent.kde.org/multimedia/kdenlive/-/commit/53eeae20b7181e5a984745b5c8f561c63901a9fb