I did not find any libav 9.14 package for Ubuntu (any version), so I finally compiled it myself on Trusty, from mainstream source. After converting the source video with the same command-line, it outputs the attached webm file, which works correctly in Firefox.
In order to check that the issue did not come from the patches of Ubuntu (or the compilation options I used), I also compiled version 9.13 from source, and reproduced the issue in Firefox. So version 9.14 of libav solves the issue. It's certainly the same issue as in the libav bugtracker mentioned above : a bug in libav that makes it generate corrupt webm files. Would it be possible to upgrade libav to 9.14 in Trusty? ** Attachment added: "WebM file generated on Trusty with libav 9.14" https://bugs.launchpad.net/ubuntu/+source/libav/+bug/1323822/+attachment/4149877/+files/P5270914-trusty-avconv-9.14.webm -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1323822 Title: Firefox can not play some WebM videos generated by avconv on Trusty To manage notifications about this bug go to: https://bugs.launchpad.net/firefox/+bug/1323822/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
