AVI (AC3) plays too fast...

[morgensonne]

hello,

i have an avi with ac3 sound. but it's played too fast in any player. the ac3 speech is like mickymouse and the movie plays with about 29 frames per second. in nandub 'file information' it shows correct 25fps but no 'real' sound information (56000Hz, 2Channels). my ac3 filter while playing says 448kbit 48khz 3/2+LFE.

Divxfix could nothing change.

Thanks a lot
Morgensonne

[manono]

Hi-

Did you experiment with the Interleave settings (In Nandub-Audio-Interleaving)? This is from the AC3 Q&A (http://forum.doom9.org/showthread.php?s=&threadid=18318) in the Audio Forum:
90ms/90ms
120ms/120ms
500ms/128ms
500ms/64ms
160ms/160ms (Works well for 5.1 384kbps)
128ms/128ms (Works well for 5.1 448kbps)
96ms/96ms
80ms/80ms (Works well for 2.0 192kbps)
64ms/64ms
250ms/64ms
160ms/60ms
160ms/2frames
500ms/3frames
Sometimes you have to experiment with the settings before you get them right.

[morgensonne]

ist not possible to "play" with interleaving settings cause nandub only saves the video information. it can't get the right audio information. when i save an audio-wav with nandub, it's a quite and small one.

morgensonne

[Acaila]

When people experience such a fast playing audio, they usually have two audio streams with their video. One being 6 channels, the other 2 channels AC3. Is this also the case with you?

However the fact that Nandub gives you incomplete/incorrect info about your audio suggests that the AC3 stream has somehow gone corrupt. What you could try is saving the audio with "Save WAV" (audio on direct stream copy), rename the resulting file to .ac3 and run that file through AC3Fix (get it on www.divx.com) to see what comes up.
After that just mux it in with the video again while trying out the various interleaving settings Manono mentioned.

[morgensonne]

the problem is, i can't save an audio stream. nandub saves a 4kb wav file, cause he thinks there is no audio.

morgensonne

[manono]

Hi-

I don't know if this will be useful to you or not, but you might try and save it with AVI2WAV (http://www.geocities.com/agrgic.geo/avi2wav.htm).

[morgensonne]

this tool also only finds stereo with 56000Hz but it isn't.

BUT it saved an Wav file... which i loaded into BeSliced and saved it as AC3. and now there is the right ac3 sound. now i only mux it together...

morgensonne

but now i have an sync problem. at on position the movie stops for a second and the audio plays fine. since this happen the A/V is async...

[morgensonne]

Here is the error from BeSliced:

BeSplit v0.82 by DSPguru.
--------------------------
Logging start : 10/08/02 , 21:41:27.

D:\Downloads\Video\Besplit\BeSplit.exe -core( -input D:\Downloads\21.wav -prefix D:\Downloads\21_Fixed -fix -logfile C:\DOKUME~1\maxiJAZZ\LOKALE~1\Temp\BeSliced.txt -type ac3 ) -profile( BeSliced v0.2 )

[00:00:00:000] +------- BeSplit -----
[00:00:00:000] | Input : D:\Downloads\21.wav
[00:00:00:000] | Output Prefix : D:\Downloads\21_Fixed
[00:00:00:000] +---------------------
[00:00:00:032] Stream error : Sync found after 1832 bytes
[00:45:50:912] Stream error : Sync found after 103925 bytes
[00:57:58:016] | Writing D:\Downloads\21_Fixed01.ac3
[00:57:58:016] +---------------------
[00:57:58:016] Operation Completed !
[00:00:57:000] <-- Process Duration
Logging ends : 10/08/02 , 21:42:24.


What can i do???

[manono]

Hi-

Did you download this video? If so, I'd be tempted to advise you not to get someone else's crap video and make your own instead. But Acaila told me not to, so I won't.:) But I think you proved Acaila's belief that it's corrupted.

As you may know, you really got the AC3, but with .wav extension and Wave header. I can think of 4 possible solutions. First , if you didn't use AVI2WAV in Smart Mode, I'd go back and see if stripping the Audio in Smart Mode will fix it (probably not).

I'd see if I could load it into a WAV Editor and find out exactly how long the asynch is, perhaps by loading the video into Nandub, scrolling to the freeze place, and determining the freeze length. Then cut that much out at the right place. You might have to make a true Wave file out of it first-I don't know.

My third possible solution would be to divide the video using Nandub (with the audio included) into 2 pieces (at the first keyframe before or after the freeze (it would be nice if a keyframe was set at the beginning of the freeze), and then adjusting the delay by the correct amount and then rejoining the pieces. I'm not positive you can append the 2 pieces again, though, because of the different delays.

The fourth solution would require some encoding knowledge. I'd save the video without the audio. Then I'd cut the piece between the 2 keyframes that includes the freeze, and then reencode that part without the freeze frames using Trim commands in AviSynth (this requires encoding with the same codec and resolution). Then I'd splice the new piece that no longer has the freeze frames back into the video and add the sound.

If I were doing it, I'd first try the fourth solution, because I know I could do it that way, followed perhaps by the second solution. It's an interesting problem, though, and you're already half way there. Good Luck the rest of the way.

[DSPguru]

Originally posted by morgensonne
What can i do??? your stream should be fixed now.

D:\Downloads\21_Fixed01.ac3

[morgensonne]

sync is found after 103925 bytes. i think that means after 1,8123sec (103925bytes/1024*8=xxx kBit/448kBit/sec=1,8123sec "=" about 45 Frames).
45 frames also was the defect video stream. so i cutted out these 45 frames. saved it as only video and after that muxed the video with the "fixed ac3".
now the video correct and don't get out of sync after the "break"

ciao
Morgensonne