On Fri, 2011-06-10 at 20:18 +0200, Philipp Ãberbacher wrote: > Excerpts from Ralf Mardorf's message of 2011-06-10 19:24:54 +0200: > > On Fri, 2011-06-10 at 18:57 +0200, Renato wrote: > > > On Fri, 10 Jun 2011 17:58:46 +0200 > > > Philipp <hollunder@xxxxxxxxxxx> wrote: > > > > > > > Hi, > > > > sorry for abusing this list for a mostly video editing question, but I > > > > didn't find a proper list and knew that we have some video people on > > > > this list. > > > > > > > > I'd like to fix some videos that have partially out of sync video and > > > > audio, meaning that beginning at a certain point in the video the > > > > audio is suddenly out of sync by a couple of seconds. There's no > > > > constant change, the delay seems fixed once it's there. > > > > > > > > I wonder how to fix such a thing. The files are xvid encoded videos > > > > and vbr mp3 audio inside avi containers. I thought it should be > > > > reasonably easy to cut and move the audio (re-encode if unavoidable, > > > > but I know it's in principle possible without) and put it back in a > > > > container, but I didn't manage. > > > > > > > > Can someone recommend a program/workflow that would allow this? > > > > > > > > I tried: > > > > - Avidemux: seems like actual editing is not what this program was > > > > written for, couldn't figure it out, but it seems close > > > > > > > > - openshot: couldn't figure out how to separate video/audio > > > > > > > > - kino: seems to only work with DV-files, apparently takes ages to > > > > decode the file, doesn't seem to be what I need > > > > > > > > - openmovieeditor: I figured it might work by dragging the file to > > > > both a video and an audio track, but I got extremely garbled audio > > > > output, no idea what's wrong > > > > > > > > - cinelerra-cv: Doesn't start. No error message, it simply shows no > > > > window, nothing. Well, it does something with the screen, but it > > > > shows nothing. > > > > > > > > - pitivi: Doesn't seem like it can play back the video. I can drag the > > > > video to the tracks and it starts to draw a waveform, I guess no > > > > video thumbnails because of: gst.ElementNotFoundError: pngenc > > > > Doesn't seem to be able to play the video. > > > > > > > > - kdenlive: would require me to install 30 additional packages, total > > > > about 200MB, no thanks. > > > > > > > > I thought it would be a simple task, really nothing fancy. Seems like > > > > I was wrong. > > > > > > > > Regards, > > > > Philipp > > > > > > > > > > Hi, unfortunately can't give you a full solution, but only a hint: in > > > mplayer with "-" and "+" you can adjust audio/video syncronization by > > > multiples of 100ms (maybe you cand do finer, but I'm not sure). > > > > > > maybe you could then somehow record the output to a new file? > > Thanks Renato, I've played with that already and know the approximate > offsets, but that doesn't help much. I'm not sure screen recorders > typically can pause and resume, and even then it would be less than > optimal anyway due to the transcoding of both audio and video. > > Also, to clarify, those offsets are constant but only appear beginning > at a certain point in the file, imaginary example: after 97 Minutes the > offset is suddenly approximately -9600ms. Hence shifting the offset of > the whole file doesn't help. > > > I don't think so, assumed you can display the video without side effects > > in a way, that you could 'record your desktop', than you only would be > > able to record video, but AFAIK not audio. > > An app like Cinelerra can separate the container's audio and video, but > > using video apps on Linux can become a PITA ... > > > > 21.9 Improving performance > > > > For the moment GNU/Linux is not an excellent desktop. It is more > > of a server. Most of what you will find on modern GNU/Linux > > distributions are faceless, network-only programs strategically > > designed to counteract one Microsoft server feature or another > > and not to perform very well at user interaction. There are a > > number of parameters on GNU/Linux, which ordinary people can > > adjust to make it behave more like a thoroughbred in desktop > > usage. > > 21.9.1 Disabling swap space > > 21.9.2 Enlarging sound buffers > > 21.9.3 Freeing more shared memory > > 21.9.4 Speeding up the hard drive > > 21.9.5 Disabling cron > > 21.9.6 Reducing USB mouse sensitivity > > 21.9.7 Assorted X tweeks > > 21.9.8 Speeding up the file system > > http://cinelerra.org/docs/cinelerra_cv_manual_en.html > > > > ... if the app after editing should make a container again, it can > > happen that the old man became a voice like Mickey Mouse or the > > beautiful woman is transformed to a Conehead. After 12 hours using all > > resources of your computer you will know if the video is ok or not. I > > nearly have forgotten to mention, that it also can happen that audio and > > video get out of sync during this process ;). YMMV. > > > > On my machine Cinelerra always 'worked' OOTB! On Philipp's it doesn't > > run. > > > > Regards, > > > > Ralf > > Thanks Ralf, > I had looked at the typical problems but they all mention error messages > while I get none: > > ----- > > $ cinelerra > Cinelerra 2.1.5CV GIT::01dc4375a0fb65d10dd95151473d0e195239175f (C) > 2010 Heroine Virtual Ltd. > External ffmpeg > Compiled on Mon Mar 28 20:17:50 UTC 2011 > > Cinelerra is free software, covered by the GNU General Public License, > and you are welcome to change it and/or distribute copies of it under > certain conditions. There is absolutely no warranty for Cinelerra. > > ----- > > That's it, nothing else happens in the console and no visible window > appears, though an invisible does appear (I can tell from the reaction > of my window manager, it tiles the invisible window but nothing is > painted there). > > I thought cutting and aligning audio/video on a timeline would be a > basic operation and possible in every NLVE... IIRC Quentin Harley http://www.64studio.com/team is an experienced Cinelerra user, but my memory might be wrong. I know him as very helpful. Daniel James also is very helpful and author of a book about Linux multimedia. I guess Robin, who is described to this list could tell you, if they be free to give information. It might be that they are too busy at the moment, I don't know, I don't have contact, since the 64 Studio lists are ghost towns at the moment. AFAIK Windows currently should be a little bit better than Linux (I don't know, it's just hearsay), regarding to video editing. Only Macs with professional video equipment seems to be a pleasure (during my jobs I've seen working gear a long time ago, Sony Betacam + Apple etc.) :(. But I'm sure with some hints from someone who is experienced with Linux video, the task you wish to do can be done with Linux. I guess for video it's similar as for audio, an usual default install won't do it. Did you test a live CD of a multimedia distro? I'm sure some people, perhaps Quentin, use Linux successful without expensive, professional gear for video editing. Regards, Ralf _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/listinfo/linux-audio-user
