To SVCD or to CVD

[Matti Haveri]

I have been quite happy with the SVCDs I have made with my 8600 but 
now I have discovered the CVD format and I am not so sure which 
format I should use if I want to transfer and concatenate the discs 
later to DVD with minimal hassle.

Yes, CVD, SVCD and VCD will all go away the day DVD burners become 
mainstream and the DVD media becomes as cheap as CDRs are today. But 
all those standards are based on MPEG so you may prepare yourself 
with DVD in mind by encoding stuff which can be most easily 
transferred to DVD in the future.

And CVD with 48kHz audio seems to be a better format than SVCD in this respect.

Am I on the right track? Can I just rip, unmux, and concatenate 
several CVDs as is to DVDs which a standalone DVD player can 
understand?

I just encoded several test CVDs and my Pioneer 444 PAL DVD player 
played them just OK either with 44.1 or 48kHz audio. The image 
quality was slightly worse compared a SVCD although the article below 
indicates otherwise.

  ...

I have cleaned following info from an article at:

<http://www.vcdhelp.com/forum/userguides/98177.php>

Before rushing to make SVCDs you may also consider the CVD (China 
Video Disc) format.

What is CVD? First, CVD predates SVCD. 2nd, "Chaoji VCD", which 
roughly translates to "Super VCD" is like a compatibility 
specification for players -- a Chaoji VCD player must be able to play 
back SVCD, CVD, VCD 2.0, VCD 1.1 and CD-DA discs.

<http://www.iki.fi/znark/video/svcd/overview/> Super Video CD Overview

Today all "SVCD compatible" PAL standalone DVD players are actually 
compatible with Chaoji VCD players. This means that both CVD and SVCD 
formats are supported.

On the other hand, the "SVCD compatible" NTSC Region 1 standalone DVD 
players in U.S. are not forced to include CVD compatibility. The 
reason is simple: Those players are not used in China, even in theory 
(as is the case with Region 2 PAL players). Only half of the "SVCD 
compatible" R1 DVD players are currently (200206) compatible with 
CVD. Most of them are made in southeast asia, and they use C-Cube's 
microchips.

So why CVD instead of SVCD?

CVD video differs from SVCD basically only by its slightly lower 
horizontal resolution (PAL 352x576 or NTSC 352x480). This resolution 
happens to be one legal resolution for DVD video, too. As SVCD, CVD 
also uses VBR MPEG2 video encoding with up to 2441 kb/s (=2500000 b/s 
= 2,4 Mb/s) bitrate.

So the benefit of encoding CVDs is that you can use your PAL 352x576 
or NTSC 352x480 MPEG2 files on CVDs today and on DVDs tomorrow, 
without any picture re-encoding or re-scaling. This is not possible 
with SVCD, because its resolution (PAL 480x576 or NTSC 480x480), 
isn't compatible with DVD video. So SVCD files need re-encoding if 
you want to burn them on DVD later. (There are ways to convert SVCDs 
to DVDs without re-encoding, but that creates something like an 
"xDVD" and many players do not support such discs. The most common 
problem is a picture with totally wrong aspect ratio or blank picture 
in the right side of the TV screen!). With CVD you don't have that 
kind of problems, and your DVD authoring programs accept your CVD 
files!

<http://www.dvddemystified.com/dvdfaq.html#3.4>

CVD audio uses the same 44.1kHz MPEG1 Layer II audio as SVCD, but 
more than 80% of the DVD standalones produced after 1999, which are 
also compatible with Chaoji Video CD players, can play also 48kHz 
audio on CVDs and SVCDs. So, if your DVD standalone supports 48kHz 
CVD audio, you may want to encode 48kHz audio in the first place, 
especially if you intend to later transfer the CVDs to DVDs because 
DVD uses 48kHz audio.

CVD, SVCD and VCD will all go away the day DVD burners become 
mainstream and the DVD media becomes as cheap as CDRs are today. But 
all those standards are based on MPEG so you may prepare yourself 
with DVD in mind by encoding CVD with 48kHz audio which can be easily 
transferred to DVD in the future.

p.s. SVCD on a Macintosh memo and cookbook is at:

<http://www.sjoki.uta.fi/~shmhav/SVCD_on_a_Macintosh.txt>

-- 
Matti Haveri <matti.haveri at sjoki.uta.fi> <http://www.sjoki.uta.fi/~shmhav/>