AC3 Audio encoding problem...

[ElayZ]

First of all, i'm not a newb to all this stuff, i know what i'm doing.
I tried alot of things already and i can't seem to get this one right.

Here's the deal...

Normally when u want to convert avi to dvd...

(i know it isn't the best way, going from dvd to compression to dvd again, but i only have this one in avi xvid format)

So, normally u rip off the audio with virtualdub if its mp3 and make a wav of it (or 2 chan AC3 with ac3machine) to later mux again with the videofile (encoded separatly...)

For 5.1 chan audio u use vdubMOD > streamlist > demux to get a proper AC3 file
(cause if u use normal vdub u get erros because vdub leaves a wav header in the AC3 file)

Now here is the problem, when i just play the avi with wmplayer for instance, i get perfectly normal sound...

Its a 2chan AC3 [TAG 2x0000, ATSC/A-52 [Dolby AC3)] stream, but when i demux it with vdubMOD and then try to play the file with TMPGEnc Sound Player (prog that comes with TMPGEnc Studio to listen to AC3 without having to mux it again first) i get an error and it doesnt play.

And i can't add the file to dvdmeastro to author it with the video.
Meastro doesn't accepts the file, gives error.

So i tried converting it with AC3Machine to get a proper AC3 audio file, wich seems to work...

BUT when i playback the file, or author it with the video i get huge cracking sounds in the audio! Specially on loud parts.

Then i tried ripping the audio with normal vdub (with the wav header then) and re-convert it again with ac3machine... same $@#$% problem!

So here's my question, is there another good way to rip an AC3 stream from an avi, or anyone had this before and knows how to fix it.

I searched on diff sites - like doom9.org- already, can't seem to find anything useful.

I tried to convert it with different settings in ac3machine.

Settings i normally use:

- Sampling rate 48000
- Channel mode: stereo (since its 2 chan ac3 on source)
- Set delay to -101 ( otherwise u get sync problems with the video)
- bitrate 256
- Autofind gain. (i also tried checking gain 0db, no difference)

I've done this alot of times before and never got this cracking problem.
I didn't change the volume or anything. I just do it the way i always do.

btw i got the latest program versions and latest codecs so that isn't the prob.


Thnx in advance for a little help.

[Soopafresh]

http://vidphiles.com/AC3%20Cutter%20v0.1.zip

[Sakuya]

Might be TMPGENc's problem. Demux the AC3 using Vdubmod. You should just play the AC3 file with Windows Media Player or Media Player Classic and it should be fine. And encode your video as M2V and then mux them together in DVD Maestro by selecting the video and then the audio. And if it gives an error, can you please copy the error here? Thanks.

[ElayZ]

Thnx for the prog soopafresh, checking it out atm.

[edit] its a DOS prog, isn't there a GUI for this?
Or otherwise i don't exactly know how to use it...

Sakuya: tried what u said, i played demuxed_audio.ac3
(already demuxed it with vdubMOD as i said) with wmplayer instead of tmpgencplayer and the demuxed file plays perfectly also! So that was due to tmpgenc proggie

But when i do import media asset in dvd meastro, it starts checking the file, and on about 20 percent i get this error:

Cannot locate a frame SYNC word at an expected byte offset. Data might be corrupted. (0xc1070042)

And i forgot to mention earlier, i have to run it through ac3machine to change it from 23fps to 25fps (PAL)