Will I lose sound quality converting SVCD > DVD ?

[Slarty]

I'm a newbie so apologies if this sounds a bit basic.

I've been happily converting SVCD's to DVD's but in reading a lot of the posts here in the Audio section, I'm beginning to think I may be doing something wrong and am losing out on Audio quality.

Following the 'convert' guides, I've decided to stick with the DVD2AVI & TMPGenc technique and although it requires a re-encode of the video (as opposed to the IFOedit trick), I always get a working DVD mpeg at the end of it.

However, if I'm extracting the SVCD audio (using DVD2AVI), then feeding that into TMPGenc (which converts it into .mp2) and then authoring the finished mpeg elemental streams using DVDit PE (which converts the .mp2 into stereo AC3), arn't I losing audio quality somewhere?

Also, how can I extract and then author 5.1 AC3 ??

[lordsmurf]

Yes, you lose quality.

Best bet is to extract the MPEG2 files with ISOBuster and then dump them into TMPGenc. Then only re-encode the video. I'd suggest 352x480 at 3500k for the new size. Then let DVDit! re-encode the MP2 to AC3.

If your source is stereo, you won't get 5.1, and there is not real way to do it. I tried once with BeSweet (still a fake 5.1), but that program always makes my audio skip or crackle after conversion.

[wulf109]

If your converting SVCD into DVD then the sound is mp2(mpeg) because that's the standard for SVCD. Converting to ac3 won't give you ac3 audio because the mp2 only has 2-channels. Re-encoeing the video can only lower it's quality.

[lordsmurf]

If your converting SVCD into DVD then the sound is mp2(mpeg) because that's the standard for SVCD. Converting to ac3 won't give you ac3 audio because the mp2 only has 2-channels. Re-encoeing the video can only lower it's quality.

AC3 is just another format. It can be 5.1, but it can also be lots of others too, such as 2.0 stereo, which is what I use.

[Slarty]

I think you've answered my question - thanks to both !

I guess when I use DVD2AVI to rip the sound from the SVCD (which I was told was a better way to do it as TMPGenc sometimes has sync problems with audio), it just rips it as a .mp2 file with no conversion. TMPGenc is just then transcoding the audio & video streams to create the DVD compliant elemental streams ready for processing in DVDit PE.

However, DVDit PE only supports LDPCM or 2-channel AC3 so I choose the AC3 option and it converts the mpeg audio. I guess its at this point that you could say that it's loosing some quality, as it's having to re-encode the audio ?? Is their an authoring system that does support .mp2 audio ??

Slartybartfarst