Mission: Linux Video Editing

[VideoRoy]

I have been working for a couple weeks trying to move my video editing to Linux and find equivalent apps for what I do in Windows. I must say the current distros of linux Ubuntu 9.10 & Fedora 12 have come a long way and the video applications have as well.

I have found linux apps to do everything I want to do in but there a lot more steps to achieve what I want with free applications but that is okay because the quality is great if you take your time there is much better support in the community than at some (not all) of the commercial companies for windows apps.

I have settled on a couple apps for most of my work because they fit my work style. There lots of opinions but these work for me:

Cinelerra-CV for NLE
Kino for DV capture and light trimming
DeVeDe and DVDStyler for authoring DVD with menus (still looking at some others Qdvdauthor and Bombono)
Avidemux for conversion and light editing
Handbrake for coversion for iPod, Blackberry, etc.
VLC of course for playback

I will continue to try others but for now these meet my needs for Linux only.

So the reason for my post, is I have been successful editing and converting my AVI / DV and most MPEG with no problem. I also have some Beyond TV .TP (.TS transport stream) I am editing and I have just one little problem that is bugging me. Like many others have found TS typically have a audio delay which some call out of sync. However applications like VLC can play back my files no problem so I know the delay is constant and the info for the delay is in the file.

I have one example file (1920x1080 HD 90 min long) I have been using that I edited and converted with VideoReDo trial in Windows. Worked great and is a really good program by the way and I am going to purchase the new version when it comes out. The only problem is it is not available for Linux. :P

Through trial and error exporting a small couple minute clip with Avidemux, I determined my audio delay is almost 1 sec (-990 ms to be exact). I entered the delay and did a conversion and it is perfect for what I want (6 hrs later)!

So knowing the answer, I went off to find a program that could determine this automatically and give me the answer. NOTE: I do not want a converter that will fix it, I just want to know the delay offset to use in the converter of my choice which is currently Avidemux. I am trying to minimize conversions, steps and time. I have found programs that would convert and fix it but it adds significant time and steps.

I could not find a Linux app that could easily give me the answer (so far). I ran DGIndex in Wine and Windows on the file and analyzed it a couple of ways. Nice program but gave me the wrong answer of -450 ms to - 500 ms depending on what I analyzed and if I was on GOPs / I frame boundaries. I analyzed the whole files and it is always off by about half.

Sorry, for the long post but I thought some people might find it interesting. Anyone have a suggestion of some other Linux tools or Windows tools I could run in Wine to figure out this one little item.

Any help appreciated.

[filmboss80]

Follow this thread:

https://forum.videohelp.com/topic352155.html

[VideoRoy]

Thanks filmboss. I just found that thread after I posted and it is a good thread that I am going to keep an eye on. I am pretty excited about the VL Movie Creator since I am thinking it might automagiclly work with my TS files the way VLC does.

I also realized that maybe I posted my thread in the wrong forum

Right now I have tried just about all the popular editors (Kino, Kdenlinve, PiTiVi, etc.) but Cinelerra-CV is the only one that is stable on my system and was easy for me to pick up the work flow. I have been using Pinnacle Studio and other packages like that on Windows for about 7 years so the learning curve was less for me.

I have 2 basic needs besides for editing. Very simple editor for doing some light trimming and make a quick DVD and advanced editor for my big projects with has effects, transistions, full rendering control, etc.

[Mountain Man]

I don't know of an automated program to do what you are asking for, but I think I have a way that can make this more painless. Avidemux will let you export the audio of a movie you are editing to a separate file. From here you can open the audio track in audacity. Once you have both the audio and video files open for viewing, find something distinct on either track, and see when that same point happens on the other track. Dialog works well for this, but quick loud noises work even better.

To copy the audio track with Avidemux, set the audio codec to whatever format you want (so long as audacity can read it), and then select Audio/Save.

[ronnylov]

ProjectX can be used to fix some issues with MPEG-2 files like HDV. It is a java program and it works in Linux as well as other operating systems. Mostly the audio becomes in sync with video after demuxing the file with projectx.

[VideoRoy]

I don't know of an automated program to do what you are asking for, but I think I have a way that can make this more painless. Avidemux will let you export the audio of a movie you are editing to a separate file. From here you can open the audio track in audacity. Once you have both the audio and video files open for viewing, find something distinct on either track, and see when that same point happens on the other track. Dialog works well for this, but quick loud noises work even better.

To copy the audio track with Avidemux, set the audio codec to whatever format you want (so long as audacity can read it), and then select Audio/Save.

Thanks Mountain Man. I thought about that this but have not gone further on the thought yet. I can do it visually and a little trial and error by exporting a couple of seconds of with a couple of audio delay and just check it then repeat till I get it. Hoping for a little more automated.

Using your method might save me some time.

ProjectX can be used to fix some issues with MPEG-2 files like HDV. It is a java program and it works in Linux as well as other operating systems. Mostly the audio becomes in sync with video after demuxing the file with projectx.

Thanks ronnylov. I am hoping to not have to demux the whole thing but I could probably automate it with some scripting.

I appreciate the ideas.

[Mountain Man]

One more thought. I don't have a file like you are describing to test this on so I can't say if it will work, but you might see if the info you want is output by mplayer:

mplayer -frames 0 -identify videofile.avi

By the same token, you might see what ffmpeg has to say about it:

ffmpeg -i videofile.avi

I haven't seen such a field from either, but it is worth trying just in case it only shows up when there is an offset coded in the file. Mplayer reports a great deal of info with that command, so perhaps I've overlooked the specific field.

Another possibility would be to write a script to strip out the audio and video streams to separate files and compare the durations. My guess is the difference in length is pretty close to the offset needed. It wouldn't make sense to have an offset and then have extra audio which didn't belong. Then, you could create an audio file of silence to cover the exact gap, add that to the front of the original audio and recombine the audio with the video. All of what I just described could be done via command line tools in linux. If you are interested in this approach reply back and I'll look up the key commands.

[ronnylov]

There is a command line interface for projectX so it can be scripted if you need it. I always use projectx to fix my TS files and mostly all sync problems are fixed by demuxing with projectx and then remuxing it again with some other program, like AviDemux.

[Einix]

Thanks VideoRoy,
I try to do the very same thing and almost thought I would be the only one who had this kind of problem

For the demux of my *.ts files I am using PVAStrumento (http://www.offeryn.de/pvas_2_1.htm) with wine. I am very happy with this program since I am using it for years on Windows and also didn't find somethig like it for Linux. The nice thing is, that it can extract somehow the time shifts and exports them to files for Cuttermaran and MPEG2Schnitt.
Under Windows I used Cuttermaran for cutting and muxing. However, it needs much of the .Net Frameworks, so I was not able to run it with wine so far.

With your idea of using the time shift info in AviDemux ( which I also like pretty much, it is the only tool that I found so far, which is able to write *.ts files that I can play on my Dreambox) it could work. The MPEG2Schnitt time shift output of PVAStrumento is binary, however, the one for Cuttermaran is an XML file. So maybe I will have a closer look to that file tomorrow and check if I could feed it into AviDemux.