Other Video CD's:

UPDATE - 31 August 2000: There is a lot of confusion associated with the other forms of the Video CD, in particular with what is known as a XVCD. Depending on which discussion site you read a different interpretation is often given. This information update has been supplied by Roberto in Mexico, a friend from the very start of my VCD involvement and very experienced in producing XVCD's. The information is based on that derived from the RAITE FAQ site.

EXTENDED VCD (XVCD):

What is a XVCD video CD, or "extended video CD"?

It is actually a VideoCD according to the VideoCD 2.0 standard, but with MPEG videos (MPEG-1) encoded into higher resolution data rates of up to 3.5mb/s.

Currently we have VCD (1.0, 1.1, 2.0 and 3.0), VideoPerfect (2xVCD), CVD (by CCube), HQVCD (by VideoCD Forums) and SVCD. The SVCD specification covers both CVD and HQVCD.

The XVCD actually confirms to both VCD and SVCD specifications. Therefore XVCD is a valid all encompassing name.

Any SVCD player will play XVCDs up to 2.6mb/s. The same goes for DVD players that support SVCD.

Advantages: - Higher picture resolution - Higher bit rate = fewer compression artifacts and therefore a better picture

Disadvantage: - Plays only on SVCD capable (external) DVD Players ("only " VCD capable DVD Players do not play those CD's) - Goes at the moment only with MPEG-1 video - Produces big files.

Which resolutions are supported? - 352 x 288 (PAL - 25 fps) - 352 x 576 (PAL) - 480 x 576 (PAL) - 352 x 240 (NTSC - 29,97 fps) - 352 x 480 (NTSC) - 480 x 480 (NTSC)

Data rate: MPEGs can use a data rate of from 1150 up to 3500kBit/s.

As everyone can imagine: with such high bit rates, less time fits on the CD (with 3500kBit/s, less than 30 minutes). The audio data rate must be 224 kBit/s as VideoCD specification indicates.

COMMENTS: Its interesting that all program providers have a different interpretation, for example, in standard VCD's the Panasonic encoder allows a combination of video and sound up to 1376kb/s and it or Nero allow it as compliant.

The listed formats do not include that which so many people use on the Pioneer 525 as not one frame size is related to a 720 or 704 width, which I believe, like a great many others, is the highest VCD standard available to us (if your lucky enough to have equipment to play it). People have called these X or HVCD's???????

Finally, I have seen postings that mention SVCD as being encoded in Mpeg-1, I would suggest that this information indicates they are actually XVCD's and not SVCD's. Confusing - sure is!

I am sorry if the experts think this is old hat!

http://www.geocities.com/aussie01au/

-- Ross McL (rmclennan@esc.net.au), August 31, 2000

Answers

Ross,

I do believe that XVCD covers video cd's between VCD and SVCD and a little higher. The only truly supported video resolutions under cd-r media are 352x240, 352x288, 480x480, and 480x576?. Any other resolution is a viloation of specs. XVCD and HVCD's I would consiter non-standard and as always, you take the risk of compatibility when using those formats. And one more confusion, the SVCD spec under the CVD coves use of mpeg1 data. This formatting of SVCD is little known and I have yet to find hard data on the specs for mpeg1 so user beware.

I would also like to confuse the mix a little more with DVCD's. These pressed disks comming out of asia are a special form of mass produced VCD's. They are special because they are longer than 80 minutes. Some of these disks have been known to store 130 minutes of video. For every minute that they add to the disk it becomes more and more likley that your player will not support it, as even 99 minute media is too much for most drives to handle. Thankfully these disks, besides their size, are standard VCD's in all other respects.

To keep it simple I have always tried to keep to the spec. For the most part I use SVCD, it is very flexable, and does a good job. It is also more likley to play on PC's and standalone players.

-- eric (eric@nospam.snowmoon.com), August 31, 2000.

Thank you Ross for a post clearing about some of the confusion, which is what was needed. Eric, i diagree with you slightly my xvcds play great on my PC and dvd players, but it hates super vcds and will not play them (unless i hook up another program which i do not want to do). For me the xvcd format is easier to use and easier to handle then a supervcd.

-- Doug (mazinz@aol.com), September 02, 2000.