tv dvd

[dns2k]

Ok i am making a tv show dvd with 7 episodes each in mpeg 1 format. i have tmpgenc dvd author and encoding program.

the problem is in the audio i have a 4 second difference in the mp2 and the m1v files in split audio.

so basically the dvds i have authored are losing audio time and it is desyncing the the video. is there a way i can encode these to not lose audio quality and keep the sync?

each mpeg is about 450mb in size

i have read the guides but i dont know how to fix my audio sync. all help would be appreciated.

-dns

dns2k2@irsoftware.zzn.com

[Dimmer]

Welcome to the forums.

You need to provide some more info:
Are you encoding to MPEG-1 yourself, and if so, why don't you use MPEG-2?
Is it NTSC or PAL? You might have set a wrong framerate for the video such as 30fps instead of 29.97 for NTSC during encoding for example.
Are video and audio originally have the same length? Otherwise you can't expect it to work properly.
What exactly do you mean by split audio?
Anyway, you can probably solve your problem by adjusting audio to the precise length of the video. Although there are some audio editors that can handle mp2, most likely you'll have to convert it to .wav and insert silence, cut or shift the beginning or the end etc. to bring it in sync. Since it's a TV show, I don't think you'd notice any substantial loss of quality after re-encoding to .mp2.

[dns2k]

ok these are mpeg 1 files i have accumulated from vcds i have.

they are ntsc

they are all in 1 mpeg file and work perfectly on the vcd and on the computer as an mpeg when i try to encode to dvd or author they come up with desync'd audio.

what program would you recomend to edit the audio and do you think the problem is at the begining or end of each file?

also what is the best way to go from mpeg1>mpeg2 without substantial desync of audio?

thanks for the welcome to the forums i have been reading here for months now and took forever to register.

-dns

[Dimmer]

Okay, for now I suggest you don't re-encode the video to MPEG-2. It's a tricky process that'll take hours and likely to reduce the video quality. Anyway, it has nothing to do with audio sync.

Normally, if you just open AVSEQ01.DAT from VCD in TMPGEnc DVD Author, it should keep audio in sync. Otherwise you'll have to investigate this a little further. Here are some things you can try; you'll need the original TMPGEnc.

1. Open MPEG Tools in TMPGEnc, go to De-multiplex, open your VCD file. Note the bitrate of the audio stream like 192kbps or so. Double-click on video and audio streams and save them as .m1v and .mp2

2. Try to author a DVD with these two files and see if there is any difference. If audio is still out of sync, notice whether it's in sync in the beginning and whether it comes early or late at the end. While in DVD Author, notice the video length in Chapter Cut Edit window.

3. There are few audio editors that can handle .mp2 files like CoolEdit. For casual editing I usually use Nero WaveEditor that comes with Nero. It accepts only .wav files, so you would need to convert .mp2 to .wav in TMPGEnc. Press Ctrl+N, open your .mp2 as an audio source, in settings change stream type to Linear PCM, click Run. Since we're troubleshooting, I suggest you author a DVD with the new .wav audio track instead of .mp2 and see if it's in sync. If yes, go to step #5.

4. Open the .wav file in Nero WaveEditor and compare the total audio length in the right bottom corner to the video length in step #2. Both values are accurate to the second. If audio has different length from video, select all and adjust it in Tools - Time Correction. If the length is the same, I can only suggest experimenting by stretching or shrinking the audio until you get it in sync with the video. Of course, each time you'll have save the .wav under a different name and re-author your DVD. You can cut and paste little pieces of silence in the beginning or end if required.

5. When you finally got the audio in sync, encode your audio back to .mp2 in TMPGEnc. Now choose your .wav as audio source and set MPEG-1 Layer II as stream type. Set bitrate to the original value from the step #1. Author the DVD with the new .mp2. If by any chance it's out of sync again, you'll have to use .wav audio even though it takes more space.

Hope this helps.

[hendrix]

@dns2k
maybe your async audio problem is due to the fact that your DVD play cant handle mp2 audio well. mp2 audio is not a NTSC DVD standard but it is a PAL standard although there are some NTSC DVD players that handles mp2, you may want to convert your .wav to .ac3 @ 192k for maximum compatibility...

ive experimented with mpeg1 by converting it to an mpeg2 video and re-encoding the wav into .ac3 and never had a sync problem

hope this helps :cool:

[Dimmer]

Originally posted by hendrix
maybe your async audio problem is due to the fact that your DVD play cant handle mp2 audio well. mp2 audio is not a NTSC DVD standard but it is a PAL standard although there are some NTSC DVD players that handles mp2, you may want to convert your .wav to .ac3 @ 192k for maximum compatibility...That's a very valid comment. Of course, if a DVD player can play VCD, it means it recognizes .mp2 format. If this is indeed a reason for the original problem, the audio will stay in sync once converted to .wav. After that, it can be converted to .ac3, preferably at the original .mp2 bitrate but not less than 192kbps.

[hendrix]

Originally posted by dimmer
That's a very valid comment. Of course, if a DVD player can play VCD, it means it recognizes .mp2 format. If this is indeed a reason for the original problem, the audio will stay in sync once converted to .wav. After that, it can be converted to .ac3, preferably at the original .mp2 bitrate but not less than 192kbps.

true, i wouldn't go less than 192k.

but dns2k stated "the problem is in the audio i have a 4 second difference in the mp2 and the m1v files in split audio."

which leads me to believe that he/she authored with a DVD with .mp2 audio. from what i understand is VCD is a supported format in DVD Players, but mp2 audio is not a NTSC DVD Standard, yet...i say go .ac3 for maximum compatibility

[Dimmer]

Okay, I got it! VCD audio has sampling rate 44.1kHz, but TDA thinks it's 48kHz. That's why it's going out of sync.

dns2k: You should re-encode your .mp2 into either .mp2 with the same bitrate or .wav specifying sampling rate 48kHz. You can use TMPGEnc as I described above; BeSweet will do, too. Obviously, your DVD player can play .mp2 sound, but if you want maximum compatibility with all the standalones, use either .wav or convert it to AC3.

[hendrix]

Originally posted by dimmer
Okay, I got it! VCD audio has sampling rate 44.1kHz, but TDA thinks it's 48kHz. That's why it's going out of sync.
forgot about the sampling rate, ya resample your audio to 48. if you go the .ac3 route be careful of using BeSweet...ive read that .ac3 produced by BeSweet isn't fully compatible with DVD Players, as it was a beta feature anyways...if i remember correctly the newer versions doesn't export to .ac3 anymore, correct me if im wrong

[Dimmer]

Originally posted by hendrix
ive read that .ac3 produced by BeSweet isn't fully compatible with DVD Players, as it was a beta feature anyways...if i remember correctly the newer versions doesn't export to .ac3 anymore, correct me if im wrong Yeah, they dropped AC3 support in BeSweet because it had poor quality and wasn't fully DVD standard compliant. I made a couple of dozens of DVDs with TV capture content using BeSweet AC3 conversion, worked fine considering that I didn't expect exceptional results anyway. There is pretty much no freeware AC3 encoders left nowadays.

[dns2k]

thanks guys.... i seperated the video and audio streams prior to posting and saw that their running time was different by 3 seconds.

i will attempt to do what you suggested dimmer now. i tried usind dvdlab because in the mirc room it was suggested but it just hangs when it starts the encode of the mpeg1 files.

i have besweet and i will rip the tracks that way and make sure i have it set to 48 khz.

thanks

dns