Why downsampling to 44.100?

[gort9k]

It seems to me that many of us convert DVDs into VCDs and, afterwards, put those VCDs into DVDs.
I know that VCd standard says that audio must be sampled ay 44.100Hz. But DVD audio must be at 48.000Hz. So when we convert VCD into a DVD (using an authoring program) the audio stream is converted back to 48.000.
When I make a VDC (DVD2AVI) I do not downsample audio, I keep it at 48.000, it makes a difference. Taking only about 6 or 7 minutes to create the false avi, instead of more than one hour downsampling audio to 44.100

[adam]

You downsample because that is what the VCD standard requires. Yes most dvd players can still play a (S)VCD with 48kHz audio but many can't and I would guess that most standalone VCD players definitely wouldn't be able to. If widespread compatibility is not too much of a concern for you, and you know you will transfer your VCDs to DVD later on, then go ahead and use 48kHz. Just so you know though, dvd2avi is extremely slow at downsampling. If you use something like ssrc it takes substantially less time and is at least as good a quality.

[gort9k]

Thanks, adam, for your comments.

Yes, I know that VCD standard claims for 44.100Hz audio and 1150 bit rate.
But, when you process the VCD movie through an authoring program (TMPGEnc DVD Author, DVD-LAB, or anyone else) the audio gets converted back to 48.000 in order to comply with DVD standard. So I can see the point of downsampling if you want to store the movie in VCD format, but to get it back to DVD..., simply, I think it is a waste of time.
Of course I can be wrong, surely I am, but I am a new comer in this video field, and I still am sorting things out

[adam]

Yes it would be a waste of time, and possibly some quality, but then again many would probably say the same for converting to VCD only to later convert to DVD.

If I may make a suggestion...If you are holding off on getting a dvd burner than you may want to consider making CVDs instead of VCDs. CVDs are very similar to a SVCD except they use a resolution of 352x480/576, which is also DVD compliant. You will preserve alot more quality by using CVD as your intermediary format and it transfers to DVD just as easily as VCD. You should see a huge difference in quality. You get twice the resolution, more than twice the bitrate, interlaced support, and you can encode in NTSCfilm (23.976fps.) You can use NTSCfilm with VCDs also, but then you will have to convert it again when transferring to DVD so it would kinda defeat the point. For the most part, CVDs play on pretty much any DVD player that can play SVCDs. If your current player doesn't support CVDs then you can buy a cheap Apex for as little as $40. I think this is a small price to pay for the huge increase in quality.

[gort9k]

Thanks again, adam.

I shall try and explain myself.

You are right when you say that it doesn't make any sense convert from DVD to VCD and, later, convert them back to DVD. I do this in order to be able to store several movies into a DVD disk.

My standalone DVD player (LG 5812N) does not recognise SVCD, so I started coverting movies into VCD format (never thought of CVD, that's true). Afterwards a friend of mine suggested taking several VCD movies, adding a menu and storing them into a DVD. That is what I'm doing right now. I use DVD-Lab as my authoring program, is the best one I've tried.

So far I've been using VDCs, but I'm going to follow your advice and try CVD, and, later on, maybe, SVCD. But I'm not so sure about SVCD, it takes almost ten hours to convert a movie.