-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Patrick Shirkey wrote: > Hi, > > I have just spent the past few days working on a project to sync a badly > recorded a/v track. > > In the process I have had to do a crash course in Linux Multimedia apps. > > It's like going back 5 years compared to Linux Audio. I haven't had to > do this kind of compiling for quite some time with Linux Audio apps due > to the Fedora yum repository being upto date and the stability issues > for basic operations have been sorted. Most of the audio apps I use just > work on 64 bit for basic editing tasks. > > I have used several programs in my quest for a/v sync. > > Avidemux > openmovieeditor > kdenlive > LiVES > cinelerra-cv (community version) > kino > > I have also used > > ffmpeg > mencoder > mplayer > gmerlin > > I also would have liked to try out jahshaka /cinefx and cinelerra-4 but > I couldn't get either installed. I ended up using avidemux and > openmovieeditor. > > I had to install several apps from source due to various bugs that > happen on my dual core amd , fedora 10 x64 packaged versions. Many of > the apps have got Fedora 10 rpm builds but it took several hours of > searching google to find the links and details for installing them. Then > I had the headache of figuring out why libs that were compiling and > installing were not being found as deps. Why does Fedora not setup the > qt4 and pkgconfig paths by default? Has that been fixed in Fedora 11? > For a development install this seems like a prerequisite. > > In the end after 30 hours of trying to use the various apps above to > realign a single audio track the best I could do was to extract the > audio track from the original with mplayer -dumpaudio, cut the original > mpg with avidemux, render (export) the new track to disk, split off the > audio track with mplayer, import the original audio track to audacity, > cut it to the right start points, export it to wav, import the new > tracks to openmovieeditor, align them, export them to .mov. 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. 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. 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 would have preferred to use one app but none of them could do all of > the above or if they could they were buggy and kept crashing or couldn't > read the mp3 or couldn't export the file in a readable format, etc.... > Kdenlive looked like it would be almost perfect but it kept crashing, > openmovieeditor is also good but editing is limited and buggy, of them > all avidemux was definitely the most rock solid performer and the > interface was a pleasure to work with. LiVES has a nice clean interface > too but is not really an editor. The other apps left a lot to be desired > in the visual appeals dept. Why do multimedia devs insist on using the > gui libraries like sdl and tkinter? > > BTW, why the different jargon for audio (export) and video (render) > processing? I guess that's because historically they were coined and used by different departments. BTW. Audio-export is still often called "bounce" (analog tape-tracks). Rendered or bounced tracks are always processed-data. However an "Export" can also just be raw-data & edit-info. Modern Workflow has somewhat blurred the lines here. > 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 48kSPS). > 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 framerates. > Through all of this process I have been consistently amazed at the state > of Linux Multimedia apps. Maybe it's just my Fedora 10 64 bit system but > it seems to me that Linux Audio Apps are a good 5 years ahead of Linux > Multimedia. yes, if not 10-15 years. While most core features have been present for quite some time, there's a huge gap when it comes to interoperability, usability and proper front-ends. > However I was glad to see that most of the apps had JACK > support which made editing and listening a lot easier. > > I still had to close all the apps occasionally because the fedora > mplayer doesn't have jack support and pulseaudio jack support isn't > obvious to setup. have you tried `mplayer -ao jack <file>` "Could not open/initialize audio device" ? -> recompile mplayer ;) > If the multimedia devs can get jack support right why > can't the pulse audio team? > > I have a new level of respect for the amazing progress that Ardour > represents for Linux Audio and *cough*soon*cough* to be multimedia > (xjadeo). Ardour is without a doubt the most advanced and stable editing > system we have to work with. > > I can see now that Ardour could well become the defacto "multimedia" > editing suite for Linux if work continues and we continue to support the > developers. > > I would like to give cineFX (jahshaka) a shot too once I get the > openlibraries to install. > lumiera.org is on the horizon. > Cheers. > -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iEYEARECAAYFAkoApSMACgkQeVUk8U+VK0K+xgCgoeI0uS7fGT9rWRAW0juQjy5t FKYAnjhXZMbE/gSKX13tjt6wFaGWiiCl =978M -----END PGP SIGNATURE----- _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/mailman/listinfo/linux-audio-user
