Join Multiple WAV files with mplayer, mencoder, or ffmpeg?

[kastion]

I'm using mplayer, mencoder, and ffmpeg to convert videos on my server through a webpage. I need to join multiple videos together. After that i need to convert them to 3GP, that is fine - I'm already doing this. I'm joining all my video files, but I don't know how I can join all the .WAV files to then put the audio & video into the 3GP file.

Can anyone give me a hand? Is it possible to join .WAV's with any of the 3 programs I listed?

Thanks.

[celtic_druid]

None of them can join files as far as I know. Generally you would use cat to pipe or something like that. As for muxing to 3gp, you can use mp4box for that.

[kastion]

None of them can join files as far as I know. Generally you would use cat to pipe or something like that. As for muxing to 3gp, you can use mp4box for that.

Thanks for the reply. I'm not having a problem with the 3GP file, the only problem im having is concatenating multiple WAV files together before creating the 3GP. I'm using mencoder to join the video files.

Are there any windows command line tools that can combine wav files?

[redwudz]

Possibly, though I generally use the freeware Audacity for that. It works just like a word processor, you just cut and paste the WAVs end to end.

I'm not sure exactly what you are doing, but if you join the video files, then process them separately from the audio, then join the audio files, then process them, then mux it all back together, you may end up with some sync problems. That's a lot of joining of separate parts and if any of them have joining problems, you will have sync problems.

If the audio and video are interleaved to start with on your videos, can you just leave them that way and join them all first? Then convert the video, extract the audio and convert it and mux it back in? Several ways to do this, but as I mentioned, Audacity works fine for audio joining. It can output a WAV, or MP3 if you have Lame installed.

And welcome to our forums.

[celtic_druid]

I believe sox can do it. Using cat should also work, although I guess you need to remove the headers first.

[kastion]

I believe sox can do it. Using cat should also work, although I guess you need to remove the headers first.

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Thanks, SoX works great, I can join all my files together, but I can't get it into 3GP container. The video works but there's no sound. I know my method works because I do it with individual videos (not split/pieced together) the same way.

I do this to every video file to get the audio:

mplayer.exe -vo null -ao pcm:file=File.wav -af resample=8000,volume=+4db:sc J:\Storage\Temp\MyMovie.avi

Then I join the audio files created with mplayer with sox just doing a simple

sox.exe J:\Storage\3GP\INTRO.wav J:\Storage\3GP\INTRO2.wav J:\Storage\part1.wav

I do that 3 times to get all 4 audio files together in one.

There's two problems I'm getting at this point:
1) Theres speech in one of the clips, when joining them (the very first two files) the length of the sound increases, and the voice is all looowwww and slow

2) Where's the header? I think that's why I can't put the audio file into the container, from what I can tell the final WAV file has no header information.


Does anyone know what causes the slow down of certain sounds when joining WAV files with SoX?

Anyone know if I can write a PCM header with SoX to the file when it makes the final copy?
If not can you do it with mplayer or any other command line tool?

Thanks in advance, this had troubling me for days now.

[kastion]

Managed to find out the hands free method I wanted for doing this. I originally was doing this, take the 4 videos, strip the audio/video (mencoder/mplayer), piece all the video together (mencoder), piece all the audio together (sox) then put them in the 3GP container (ffmpeg).

What I'm doing now isn't any easier, in fact it's probably much harder, but it works.

Mencoder can join avi's as long as they have identical headers it seems, so I take my 4 videos, split the video/audio, and make 4 new avi files with the same codecs. Then I join those 4 files into 1, split that file (changing video/audio to a phone friendly format in the process) and put it in the 3GP container.

Yeah...woooo that seems like alot but it's really not. I'm sure I'm probably loosing quality along the way, but because it's for mobile, what ever the other stuff I'm doing could cause is negligible.

Thanks everyone for the help along the way. celtic_druic - SoX is a wicked program I just wish there was an easy way to write file headers.

And thanks redwudz glad to be here I've been reading this forums for a while but only recently joined.