Sync problem: 3 SVCD thirds -> DVD

[frostbyte]

OK, I... acquired this movie which spanned 3 SVCD discs. I thought to myself how nice it would be to put this onto 1 DVD-R. I had done this with music videos using bbdemux and MMT/MMMT like:

1. Demux,
2. resample mp2 to 48000khz Wav/PCM
3. reencode Wav to mp2
4. remux as mpg
5. Author as DVD with VIDEO_TS folder using MMT

This works beautifully for small music videos, but when I try this method with this movie it doesn't work so well, the audio becomes increasing out of sync. I basically cut the overlap off of the ends and joined all of the mpegs together. This big 2.3GB mpg plays fine, no sync issues. But when i run it thru steps 1-5 above it is off by about 1.5sec at the end, very annoying. I have tried:

Demuxing DVD-authorable mpeg file, then remuxing

I also tried splitting a test file, running steps 1-5 on both chunks, then rejoining, but it skips terribly at the split point. Any help would be greatly appreciated. If you fix this problem easily for me I will send you a copy!

[AntnyMD]

When you rejoin the original three chunks (edited or not), this is what causes the sync issue. It's nearly impossible to avoid. If you use DVD Studio Pro, you can import the three chunks (with audio resampled), and use them as three separate tracks. Then, add Markers at the beginning of the second chunk, and at the beginning of the third chunk, to trim off the overlap from the previous chunk. Once thats done, link the three segments: the first chunk gets linked to the first Marker of the second chunk, and the second chunk gets linked to the first Marker of the third chunk. Although you will still experience a slight pause as the DVD changes title sets, you won't have to hear/see snippets of repeated movie. My suggestion is a bit more involved, but you won't have a sync issue any longer.

[frostbyte]

So I demux each file, resample the mp2 to 48000, the remux them individually, then import each of the 3 remuxed files into dvdsp? I thought dvdsp would only work with demuxed files? I'll being to try this and wait for more replies, thank you for the first reply.

[AntnyMD]

I didnt stipulate to leave the files demultiplexed as I assumed anyone who has tried to use DVDSP knows it only accepts demuxed files. I'll be more clear in the future.

[frostbyte]

Yup, I have never used DVDSP, but I will try it out since i just got it recently, thanks.

[ZeroSix]

I agree with everything here.

Be aware that using DVDSP will not be allowed directly for a few reasons.

SVCD has a resolution of 480x480 and DVDSP requires a resolution of 720x480 for NTSC. Furthermore, you must ensure that your framerate is 29.97 and not the 23.98 which is common among SVCDs. If you do not meet these guidelines, then DVDSP is useless to you.

I recommend a very simple procedure.

1) You state that the joined MPEG files play just fine before being demuxed. Is this correct?

2) If this is the case, you could use Mencoder to convert it to a very VERY high quality Divx File that would result is minimal quality loss. so minimal that is isnt even noticeable.

3) You can then export the resulting .AVI file to MPEG2 using Quicktime. Since you have DVDSP, you also have the MPEG2 export option in Quicktime. What this export will do is change the resolution to a correct one, and fix the framerate. This is highly recommended.

4) You can then author the resulting MPEG2 file in DVDSP --OR-- in MMT as you normally would. However you will end up with a .aif file for the audio, which would need to be converted to AC3 or MP2 if you want to conserve disk space.

The time it would take to this on a 800MhZ G4 [single processor] would be about 2 hours to convert to Divx and about 2.5 hours to convert to MPEG2 from quicktime.

All things considered, this is probably your best option. It is just a little time consuming.

[frostbyte]

Thank you very much. When I get the time I'm going to sit down and see what I can crank out, I'll let you know what worked/didn't.