DD5.1 384K to AAC5.1 384K ?

[P.J]

Hi !
I wanna encode a MPEG2 720p 59.94fps w/ DD 5.1 audio track for fixing the pitch (NTSC to PAL 104%), but premiere pro cs4 doesn't encode the audio track to DD5.1 (just 2.0) xD
But I can use H.264 + AAC 5.1. So I wanna know is it good to encode DD5.1 384K to AAC5.1 384K ? :confused:

Thanks !

[Snowknight26]

It's always a bad idea to transcode from one lossy format to another.

[madshi]

If you want to adjust the playback speed, you do have to reencode audio. No way around it, unless you want to use the MKV built in slowdown/speedup options. Now if you have to reencode, anyway, encoding to AAC 5.1 is just fine, as long as your playback system can handle it.

[P.J]

ok, i use mkvmerge to speed up the audio track (100/104). No sync problem, but it doesn't shift the pitch xD
It seems it stretch the video track :(

[madshi]

I've never used this specific mkv functionality, so I don't know how it works exactly. If all else fails, you can still reencode the audio track. E.g. you can do:

eac3to source.ac3 dest.ac3 -speedup [-bitrate]
eac3to source.ac3 dest.aac -speedup

Doing this, the pitch will go higher. If you don't want the pitch to be changed, you need to use a different algorithm, one which includes pitch correction.

[P.J]

yes, i wanna shift the pitch not the speed !

[madshi]

yes, i wanna shift the pitch not the speed !
That directly contradicts your original post where you said:

"I wanna [...] for increasing the playback speed"

[P.J]

Yes, you're right xD

[P.J]

I've never used this specific mkv functionality, so I don't know how it works exactly. If all else fails, you can still reencode the audio track. E.g. you can do:

eac3to source.ac3 dest.ac3 -speedup [-bitrate]
eac3to source.ac3 dest.aac -speedup

Doing this, the pitch will go higher. If you don't want the pitch to be changed, you need to use a different algorithm, one which includes pitch correction.

My file is MPG. Should I export its audio track (ac3) ?
How can I use eac3to GUI to convert it (too many settings) ?

[P.J]

Sorry, I'm newbie xD
Would you explain more ?

[madshi]

Nobody can help you, unless you explain what you want without contradicting yourself.

[P.J]

It seems my file has been converted from PAL to NTSC. so it has pitch problem and its audio track format is DD5.1.
I think it's enough :(

[madshi]

Well, then comment #5 in this thread should do the trick.

[P.J]

Yes, I know, but it seems I should export the audio track first to *.ac3. so is there anyway?

eac3to source.ac3 dest.ac3 -speedup [-bitrate]

Is it correct: eac3to source.ac3 dest.ac3 -speedup 104/100 -bitrate 384

(The difference of speed between PAL and NTSC is 4%)

[tebasuna51]

If
eac3to source.mpg

EVO, 1 video track, 1 audio track, 0:00:24
1: MPEG2, 576i50 (16:9)
2: AC3, 2.0 channels, 384kbps, 48khz, dialnorm: -27dB, -18ms

You can use:
eac3to source.mpg 2: dest.ac3 -speedup -384

without '104/100' and 'bitrate'