MP3 to AC3 conversion using ffmpeggui

[=CrAzYG33K=]

Ok.. I separated the mp3 audio stream from my avi file into a *.wav file using vdubmod and now I converted it into *.ac3 using ffmpeggui.. but I see the sound volume has decreased.. Is the AC3 better than MP3? Is it actually 5.1 surround? In that case does the sound volume reduce??

[guns1inger]

Is AC3 better than MP3 ?

For quality, yes. MP3 destroys audio. For use in an AVI, it's not as generally playable and probably takes up more space.

Do you have 5.1 surround ?

No. You only had a muddy MP3 stereo track to begin with, so the best you could hope for is 2.0 without a lot of work on your part. ffmpeggui can only produce 2.0 AC3, although apparently the latest version of ffmpeg supports 5.1 encoding. Regardless, encoding as AC3 does not automatically give you 5.1

As for the volume change - too difficult to explain, but search for Dynamic Range Control and Normalising to get more details. Suffice to say, converting MP3 to AC3 will not improve your quality or give you 5.1 surround, and is a waste of time for an AVI. If you had an AC3 DVD sourced audio track, it would be worth it.

[celtic_druid]

By the way, ffmpeg/ffmpeggui can handle an avi with mp3 audio as input. No need to demux/decode first.

[=CrAzYG33K=]

Does the latest version of ffmpeg really provide 5.1 encoding?? I tried besweet with AC3enc (lame) I've got an AC3 O/p from MP3 file .. but how'd I check if it's actually 5.1 and not 2.1?? G-spot din't help

[celtic_druid]

Far as I know ffmpeg has supported 5.1 AC3 encoding for ages. Probably as long as it has supported AC3 encoding. You need a 5.1 source though. Same would go with BeSweet. I mean I guess you could tell either to encode 6 channels, but I would think that the other 4 would just be silence.

[=CrAzYG33K=]

Far as I know ffmpeg has supported 5.1 AC3 encoding for ages. Probably as long as it has supported AC3 encoding. You need a 5.1 source though. Same would go with BeSweet. I mean I guess you could tell either to encode 6 channels, but I would think that the other 4 would just be silence.

Oh thanx -- that was informative...
But how'd I get a 5.1 channel MP3!! That's damn foolish! Or am I wrong?

[ZippyP.]

Is the AC3 better than MP3?

Your AC3 file will not be any better than your source MP3, unless you do something to "improve" it. Changing it from one format to another does nothing to make it any better.

[celtic_druid]

Well there are surround mp3 implimentations. Not what I said anyway, I just said that you need a 5.1 source, not that you had one. If you really want 5.1 and only have a 2 channel source, then the way forward would be some kind of upmix. There are various guides around for upmixing from 2 to 5.1.

[=CrAzYG33K=]

Well there are surround mp3 implimentations. Not what I said anyway, I just said that you need a 5.1 source, not that you had one. If you really want 5.1 and only have a 2 channel source, then the way forward would be some kind of upmix. There are various guides around for upmixing from 2 to 5.1.

thanx for the info .. I'll use search now! 8)