Bug 348985

Summary:	Clips with speed effect break if video properties altered
Product:	[Applications] kdenlive	Reporter:	Chris <chris>
Component:	Video Effects & Transitions	Assignee:	Vincent PINON <vpinon>
Status:	RESOLVED FIXED
Severity:	normal	CC:	qubodup, wegwerf-1-2-3
Priority:	NOR
Version First Reported In:	unspecified
Target Milestone:	---
Platform:	Arch Linux
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Chris 2015-06-10 14:58:59 UTC

As the title implies, a clip placed in a timeline can break (i.e. disappear) if the video of the clip has changed certain properties. These changes can be toggling on/off proxy clip for this video, or changing interlacing settings in the video properties. 


Reproducible: Always

Steps to Reproduce:
1) Load a video into kdenlive and create a proxy clip
2) Place the video in the timeline, crop a bit at the beginning and the end
3) Apply the speed effect to the clip and set it to > 100%
4) Save your project, reload kdenlive (not necessary but helps to reproduce)
5) Soon as you opened your project again, toggle off the proxy clip or change the interlace setting of the video (other video options work just as well). 

Actual Results:  
kdenlive will tell you that it was impossible to update the effect of the clip in your timeline. The preview monitor will also act as if the clip isn't there anymore. Soon as you save and re-open kdenlive again, the clip in your timeline is gone.

Expected Results:  
I would love to maintain the speed effect even when switching proxy clips on and off. Proxies improve the performance while the original clips help me to adjust the start and end of sped up clips greatly.

Comment 1 qubodup 2015-11-24 06:29:01 UTC

In recent git version of kdenlive..

I am not able to reproduce this issue by following your steps (2:45 the action begins):
https://youtu.be/nQVTUykn-UA

I used
https://archive.org/download/StockVideoGameVideo/TriggerRallyGeneralPurposeVideo.mp4 (MPEG4 download at https://archive.org/details/StockVideoGameVideo ) for testing.

Can you reproduce it in recent versions/with the video I used?

I have had issues with clips disappearing however but there might be additional factors required to reproduce the issue and/or it might be unrelated to the speed effect except that it favors the other factors playing a role...

Comment 2 Wegwerf 2016-07-30 11:01:16 UTC

Qubodup, as there have been changes to the underlaying speed effect producer, I would like to ask you if this problem still persists? Kdenlive has switched from the old speed effect to the new timewarp producer that also supports audio.

If your problem is fixed, I would like to ask you to close this report as fixed. Thank you very much for your cooperation!

Comment 3 Chris 2016-08-04 16:44:09 UTC

I can confirm that with the new Speed Effect (which I really like, Thank you :)) this problem is fixed. 

I did notice however in the new version that if you make a clip so slow that it would overlap another one on the same track, this clip seems to be pushed back upon reloading the project.
I need to investigate this more however and write up the exact steps to reproduce this. 

But this bug in particular is fixed.

Comment 4 Wegwerf 2016-08-04 16:56:21 UTC

Chris, if you can come up with a regression example and the steps to reproduce, this would surely be great! (I know how difficult this can be, so kudos for researching into this!) Just start a new bug report then.

Comment 5 Chris 2016-08-04 17:25:08 UTC

No problem. Already did that. :)
https://bugs.kde.org/show_bug.cgi?id=366416
I have also recorded a small video to demonstrate the bug (it's linked in the report).