[LAU] state of multimedia
pshirkey at boosthardware.com
Wed May 6 00:58:52 EDT 2009
Robin Gareus wrote:
Thanks for your useful tips.
> yay: Unix spirit: one tool per task ;)
> I'm surprised that openmovieeditor failed. It works pretty stable here
> for doing simple editing. kino even more so.
dual core amd x86_64 with fedora 10 seems to be a bit of a problem for
> As for aligning and editing audio; I'd recommend ardour over audacity.
> You can see the video in sync with xjadeo. Ardour can read timecode from
> the broadcast-info in the audio-file's header and automatically align
> chunks/regions in a session.
I'm going to look into this combination this week too.
> Your final step of multiplexing and transcoding can be done on the
> commandline. eg. for a PAL-DVD with two audio-tracks:
> ffmpeg -target pal-dvd -b 9000k -bt 1000k -i film.avi -acodec mp2 -ab
> 192k -alang en -i bounce_stereo.wav -acodec ac3 -ab 384k -ac 6 -alang en
> - -newaudio -i bounce_cinema.ac3 -map 0:0 -map 1:0 -map 2:0
> /tmp/master.mpg -author xxx -title "Title" -year 2009
> The devede(1) GUI can build this command for you.
I did try to use ffmpeg but all of my results were unplayable.
>> What I am sorely missing is a video time stretch function as the final
>> edit is still badly out of sync.
> While some software-players support it, many video playback devices are
> limited to 24, 25, 29.97 or 30 fps. - Time-stetching film by non-integer
> multipliers is tricky. google for eg. telecine, pulldown.
> Usually you're better of editing, re-sampling or time-streching the
> audio. *hint* ardour's stretch/shrink region edit-mode.
>> At least now it starts in sync but the
>> drift sets in after about 5 seconds.
> What is the cause of this? Is the source material already out of sync
> (eg. indepenent audio and video recordings)? Does it happen when cutting
> the clips (in your case: after avidemux)? or is it a problem of the
> final rendering/mastering?
> A possible mistake could be that you simply specified a wrong framerate
> or samplerate for the target.. (eg. you use 24fps source instead of
> 25fps?! or supplied an 44100 SPS audio to a PAL-DVD which should be in
The original source was recorded out of sync. It's certainly possible
that the frame rate was wrongly specified when they rendered the track
with whatever app they were using to record with.
>> Maybe I could do it with liVES or
>> ffmpeg but I was surprised that none of the apps I tried offered
>> "Stretch" as a core feature/tool.
> mencoder is your friend. It includes pullup and filmdint (inverse
> telecine) filters; and it can do crude slow/fast motion via -fps , -ofps
> That being said: you better fix the audio than tempering with video
The audio is fine but as the video is completely out of sync it probably
points to a frame rate issue.
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