Getting 5.1 audio from DVD to timeline

[Bauzi]

Hey there,

I would like to have 5.1 audio in my timeline. My source is DVD and I ripped it as usualy described in the guides and indexed them with DGIndex. I've let DGIndex export the .ac3 audio of the track and I managed to put it directly into the timeline (Final Cut Pro). I takes nice 6 audio layers for one ac3 file and I can have full controll over every layer. However there is only audio in two layers which actually is only stereo

Can somebody describe me how I get the real 5.1 audio from a dvd into my timeline? I honestly don't have a clue now

[Qyot27]

Does Final Cut recognize it if you use PCM instead of AC3? Let DGIndex decode the audio to WAV when you run it through there.

After everything's done and exported, then I'd recommend either using Aften to encode back to 5.1 AC3 (only if you've manipulated the audio in any way, of course; otherwise just use the original audio file) or use either oggenc or oggdropXP'd (through Wine) to handle encoding it to 5.1 Vorbis. I think Nero's AAC encoder supports 5.1 input/output, but I've never tried.

[Qyot27]

Does Final Cut recognize it if you use PCM instead of AC3? Let DGIndex decode the audio to WAV when you run it through there.

After everything's done and exported, then I'd recommend either using Aften to encode back to 5.1 AC3 (only if you've manipulated the audio in any way, of course; otherwise just use the original audio file) or use either oggenc or oggdropXP'd (through Wine) to handle encoding it to 5.1 Vorbis. I think Nero's AAC encoder supports 5.1 input/output, but I've never tried.

I suppose I should have asked this first, though - are you sure the particular AC3 you grabbed was the 5.1 track and not the stereo one?

Also, if Final Cut doesn't recognize WAV (I don't see why it wouldn't, but there is the whole issue it has with HuffYUV AVIs), then you'll need to take the WAV file and convert it over to Uncompressed AIFF. There shouldn't be any loss incurred, as the audio remains in PCM format - it's just changing containers.

[Bauzi]

Actually those tracks are 5.1 and once again FCP is playing stupid with only using 2 tracks. Of course my beloved Premiere Pro is using it properly

Well... DGIndex is playing stupid on me too. I check the Convert AC3 To WAV option, but nothing happens after indexing. No .wav files at all

How can I convert an 5.1 file to multiple PCM .wav files or one 5.1 PCM .wav file (or AIFF)?

[Qyot27]

I'd probably see if ffmpeg can do it. If you're okay with using the command line/Terminal, then

Code: Select all

ffmpeg -i "audio.ac3" -acodec pcm_s16le -f aiff "output.aiff"

works*. It'll output a 5.1-channel PCM AIFF file. If you want Wave instead, just change -f aiff to -f wav. If you convert to AIFF first and find it doesn't work, but want to simply change containers, still use -f wav but use -acodec copy instead of -acodec pcm_s16le.

If you're not comfortable with the CLI, then it's possible any of ffmpeg's frontends can allow you to interface with it more naturally. Whether they allow you to pass those specific options and don't downmix to stereo I don't know.

As for splitting them into 6 different files, I'm unsure of which app to use. I've never had to do that.




*That line assumes you're inside Windows. If you have the OS X command-line version of ffmpeg, it'll have ./ffmpeg at the beginning instead of ffmpeg only (at least, I had to put the ./ there in order to run it after I compiled ffmpeg on the Tiger setup I have access to). Or if you want to use the Windows version of ffmpeg with Crossover/Wine, it'll be wine ffmpeg at the beginning.

[Bauzi]

It worked with pcm_s16le. Thank you. The sad thing is that wav works much faster than AIFF for building up waveforms. Building up waveforms is so god damn slow. I better only turn them of from time to time

[Bauzi]

Mhm I think the ac3 tracks already worked too, but the audio for the scenes I zoomed in were only stereo

Either way I can't recommend to work with the ac3 tracks with a dual core (2x 2.22Ghz) Mac Book. The processing is just too slow. At least for me. I had the chance to edit a good part of the project on a quad core apple workstation. That worked pretty good with the converted .wav file.

[mirkosp]

Just like half an hour ago, a friend of mine casually linked me to this software: http://members.home.nl/thefilmmachine/.
It does make it easy to output 6 mono wav files, one for each channel, which should be reasonably easier and fast to work with. Not sure if you actually need it, since I think qyot's solution is a very good one, but perhaps it could do for a good alternative. I haven't tried it yet myself, but I'll likely have to (I'll have to do a slowdown of some pal audio and I'm not sure how eac3to's slowdown will be like, hopefully it'll pitch correct, but otherwise I'll try this program myself).