View Issue Details Jump to Notes ] Issue History ] Print ]
IDProjectCategoryView StatusDate SubmittedLast Update
0000853KdenliveUser Interfacepublic2009-05-24 23:212009-06-02 17:19
Assigned Toddennedy 
PlatformOSOS Version
Product VersionRecent git 
Target VersionFixed in Version 
Summary0000853: Project monitor preview: Audio does not match result
DescriptionI was working with two tracks, an audio (.wav) and a video (.avi, xvid) track. The video clip had audio too. I wanted to match two events exactly and was first relying on the displayed wave form (which finally proved to be correct), but was then upset by the preview (project monitor) where the video's audio came much earlier (about 0.1 or 0.2 seconds) than it should have. So I corrected the position of the video clip until the audio matched.

After rendering the project I found out that it was wrong. So I completely relied on the wave form of both video and audio and rendered a small piece of the video (hey, this feature is really nice!). It was perfectly right. Checking Project Monitor output again -- still a gap of about 0.1 seconds.
Additional InformationUnfortunately I couldn't observe this in a short test project.
TagsNo tags attached.
Build/Install MethodManual build from SVN
Attached Files

- Relationships

-  Notes
Granjow (developer)
2009-05-25 21:38

Seems to be something about the beginning of the video. For another one 0.3 seconds have been cut off, again rendering showed a correct result.
ddennedy (developer)
2009-05-27 08:08

Is the audio going through PulseAudio?

It is quite difficult to measure and ensure a/v sync as it goes through X11 and ALSA - everyone's system is different, 2 distinct APIs, there is no single clock that drives the output of them.
Granjow (developer)
2009-05-29 19:40

KDE4 shows GStreamer, if that is a PulseAudio equivalent.
ddennedy (developer)
2009-05-29 22:57

Kdenlive does not use KDE4 Phonon. So, what you see in System Settings is meaningless. However, some distributions run a sound mixing daemon called PulseAudio and then configure things to go through it by default including the SDL library that MLT uses. Do you have a pavucontrol utility that you can run in konsole? If so, run it while kdenlive is playing and see if there a volume slider widget for the Kdenlive application.
Granjow (developer)
2009-06-02 14:36

No, pavucontrol is not installed here.
ddennedy (developer)
2009-06-02 17:19

I am seeing the audio behind a couple of hundred milliseconds or so myself now. So, I will see what I can do.

- Issue History
Date Modified Username Field Change
2009-05-24 23:21 Granjow New Issue
2009-05-24 23:21 Granjow Build/Install Method => Manual build from SVN
2009-05-25 21:38 Granjow Note Added: 0002910
2009-05-27 08:08 ddennedy Note Added: 0002936
2009-05-27 08:08 ddennedy Status new => feedback
2009-05-29 19:40 Granjow Note Added: 0002972
2009-05-29 22:57 ddennedy Note Added: 0002975
2009-06-02 14:36 Granjow Note Added: 0003028
2009-06-02 17:16 ddennedy Status feedback => assigned
2009-06-02 17:16 ddennedy Assigned To => ddennedy
2009-06-02 17:19 ddennedy Note Added: 0003030

Copyright © 2000 - 2016 MantisBT Team
Powered by Mantis Bugtracker