AC3 Encoding and Muxing Question

[Lula]

Hi,

I capture from Mini-DV to my computer using Pinnacle Studio 7.
That generates an AVI file.

The DVD (NTSC) spec says mpeg audio is not standard.
So, I should go with AC3.

I used VirtualDub to extract WAV file from my captured AVI file.

Then I used SoftEncode to convert WAV to AC3 .

TMPGEnc was used to generate video stream (.m2v) from captured AVI.

Now I need to mux audio (AC3) and video (.m2v) streams.

I tried it with TMPGEnc but audio was out of sync (delayed by many seconds in regards to video).

Can anyone help ?

Thank you.

[framerman]

I am having this same audio sync problem. You can adjust the ac3 in BeSweet in a couple of ways. Is your audio the right length but offset from the video? Or does it start off fine in the beginning of your video and slowly go out of sync worse and worse as the video goes along. I'm assuming that since you are using the same programs roughly as I am that the audio sync gradually gets worse. In this case you can change the frame rate of the audio to speed it up or slow it down. Or you can add silence onto the end of the audio to compress the audio or delete some and stretch.
With BeSweet you can download it here but make sure you get the BeSweet GUI. BeSweet looks like a DOS program running. The GUI makes it easier to use in a Windows appearance. There is also ac3machine which also uses the BeSweet program. Or there is ac3delay corrector. Or Cool Edit Pro if you have it or want to buy it. Or....

[ChristianHJW]

Originally posted by Lula
The DVD (NTSC) spec says mpeg audio is not standard.
So, I should go with AC3.

If this is a stereo file go for MPEG1 layer 2 ( = MPEG2 layer 1 AFAIK ), as this is part of the DVD specs also ...

[Nic]

MPEG1 layer 2 ( = MPEG2 layer 1 AFAIK )
Not quite, Layer1 is layer1 & layer2 is layer2. they are quite different, the layers just support different samplerates in MPEG2 comapared to MPEG1.
(AFAIK ;) )

-Nic

[ChristianHJW]

Hmm ... but isnt MPEG2 layer 2 = MPEG1 layer 3 = MP3 ? Also there is a MPEG 2 layer 2.5 also ( cant remember what that is, sorry ... ) ?

[Nic]

( layer 2.5...thats one use of a sync bit I suppose ;) )

MP3 = MPEG Layer 3 the mpeg1/2/2.5 just support different samplerates (amongst other things):-

MPEG-1 layer III sample frequencies (kHz): 32 48 44.1
bitrates (kbps): 32 40 48 56 64 80 96 112 128 160 192 224 256 320

MPEG-2 layer III sample frequencies (kHz): 16 24 22.05
bitrates (kbps): 8 16 24 32 40 48 56 64 80 96 112 128 144 160

MPEG-2.5 layer III sample frequencies (kHz): 8 12 11.025
bitrates (kbps): 8 16 24 32 40 48 56 64 80 96 112 128 144 160

( For reference ;) )

So by your thinking what would MPEG-2 Layer 3 be ? ;)

Take Care,
-Nic

ps
The above text is at the end of lame --longhelp
(lame being a layer3 encoder... ;) )

[ChristianHJW]

Originally posted by Nic
So by your thinking what would MPEG-2 Layer 3 be ? ;)
-Nic
= MPC :D !!!! LOL ....

Thanks for clarifying, i was swobbing layer nrs. and MPEG itself it seems ...

[dannyv]

Originally posted by Lula
Hi,

I tried it with TMPGEnc but audio was out of sync (delayed by many seconds in regards to video).

Can anyone help ?

Thank you.

Try transcoding using rempeg. I've never had good audio sync using tmpgenc.