Audio sync / rendering issues on Ubuntu 12.04

[Tony Whitmore]

Hi,

I recently upgraded to Ubuntu 12.04 from 11.10 and have noticed issues in exported videos, which manifest as audio sync or video rendering issues. For example, the audio might be 0.1s behind the video. The speed of the video will alter around an overlaid graphic (speeding up slightly), resulting in a similar audio sync issue.

I didn't encounter these issues on 11.10 and set up a VM to test. Using Openshot to render the same .osp file at the same settings with the same source files results in a video that does not exhibit the issues described above.

I am using openshot from the OpenShot Developers PPA in both cases (1.4.2) so I presume it's an issue with the graphics processing library.
---
ApportVersion: 2.0.1-0ubuntu11
Architecture: amd64
DistroRelease: Ubuntu 12.04
Package: openshot 1.4.2-1 [origin: LP-PPA-openshot.developers]
PackageArchitecture: all
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 3.2.0-26.41-generic 3.2.19
Tags: precise third-party-packages
Uname: Linux 3.2.0-26-generic x86_64
UnreportableReason: This is not an official Ubuntu package. Please remove any third party package and try again.
UpgradeStatus: Upgraded to precise on 2012-06-09 (46 days ago)
UserGroups: adm admin audio cdrom dialout dip floppy lpadmin plugdev scanner video

[Walter Garcia-Fontes (walter-garcia)]

Thanks for reporting this issue and trying to make Ubuntu better, and sorry for having taking some time to answer.

To give more information on your problem, you need to provide information about your system by executing the following command, as it will automatically gather debugging information, in a terminal:

apport-collect 1016209

When reporting bugs in the future please use apport by using 'ubuntu-bug' and the name of the package affected. You can learn more about this functionality at https://wiki.ubuntu.com/ReportingBugs.

[Tony Whitmore (tonywhitmore)]

apport information

[Tony Whitmore (tonywhitmore)]

Hi Walter, thanks for the response. I have run the command as instructed.

[Olivier Girard (eolinwen)]

Hi,
Effectively, this issue comes from MLT. The only solution that we have for the moment is to upgrade this one. And we are not lucky because the official version in Ubuntu (0.7.4 or 0.7.6, I don't remember exactly) is full of bugs.
What is your version of MLT ?
The only solution is to update this one following this FAQ : https://answers.launchpad.net/openshot/+faq/1861
Good Luck waiting our own library.

[Tony Whitmore (tonywhitmore)]

Thanks Cenwen. The problem is that the version of MLT in the Sunab repository conflicts with the requirements of the Openshot package in the Openshot PPA. So you can't have both installed at the same time. I can't even test if the problem is fixed in the versions in the Sunab PPA because of the problem.

For now I'll keep copying everything back to an 11.10 VM to render the final video, but it's a big PITA.

[Olivier Girard (eolinwen)]

Hum, I am using currently the last version of MLT unstable i.e. 0.8.1 on precise 12.04 without any problem. And it is without guarantee that your audio sync will be resolved. I have more hopes in our library.
Here the screenshot of my dependencies if it can help you. http://pix.toile-libre.org/?img=1346270147.png

[Tony Whitmore (tonywhitmore)]

With the following in my /etc/apt/sources.list:

# Openshot PPA
deb http://ppa.launchpad.net/openshot.developers/ppa/ubuntu precise main
# deb-src http://ppa.launchpad.net/openshot.developers/ppa/ubuntu precise main

# PPA for MLT
deb http://ppa.launchpad.net/sunab/kdenlive-release/ubuntu precise main
#deb-src http://ppa.launchpad.net/sunab/kdenlive-release/ubuntu precise main

When I upgrade, only two packages are upgraded:

$ sudo apt-get upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages have been kept back:
  libmlt++3 melt
The following packages will be upgraded:
  libmlt-data libmlt4
2 upgraded, 0 newly installed, 0 to remove and 2 not upgraded.

If I attempt to dist-upgrade:

$ sudo apt-get dist-upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
Calculating upgrade... Done
The following packages will be REMOVED
  libmlt4 openshot python-mlt3
The following NEW packages will be installed
  libmlt5
The following packages will be upgraded:
  libmlt++3 melt

I don't want to remove openshot, but can't upgrade to libmlt5 without removing it.

[Andy Finch (fincha)]

That is fixed in the next version which will be released soon (bug here: https://bugs.launchpad.net/openshot/+bug/1002675)

That is included in the Daily PPA, so you have the option of using that, but with the caveat that you could experience some bleeding edge type issues.

[Andy Finch (fincha)]

Actually, I'm not too sure about packaging bugs and the daily ppa, as the packaging stuff lives in a different branch. So my comment above may or may not be accurate :-)