What Are VCDs?
Video CDs are defined in the White Book as a method to store digital video on Standard CDROM. They contain MPEG-1 (Motion Picture Expert Group) audio and video for mainly video applications. Video CDs are multi-track, CD-i Bridge discs also designed to play on CD-i players. They have become incredibly popular due to the fact that they can be played on home DVD players and PC CDROM drives.
The MPEG files must be WhiteBook compliant system streams (i.e. multiplexed, with a video bit rate of 1,151,929.1 bits/sec and an audio bit rate of 224 kbit/sec. AVI files are encoded and multiplexed by the internal encoders and multiplexer.
The Video CD specification was written by Philips, Sony, Matsushita and JVC. It is a generic format which (like audio CD) is hardware independent. The original version was for Karaoke CD as a replacement for the ageing VHD video disc systems used in many Karaoke bars in Japan.
Special purpose designed Video CD players have been developed in the Far East as enhanced CD players with Video CD capability. Generally they offer a lower cost solution for playing Video CDs, as well as audio CDs, but not other CD-ROM/CD-i discs.
The picture quality is about that of VHS Video, depending on the device/software you are using. Movies are usually placed on 2 CDs with very long movies requiring 3 CDs. The file containing the actual MPEG has got the extension *.DAT, but you could simply rename it to *.MPG for convenience, It can also be cut into smaller pieces, as MPEG is generally a headerless format.
Despite the introduction of DVD-Video, Video CD has been given a new lease of life with the many films available. Most notably, copies of pirate films such as Star Wars - The Phantom Menace and many other unreleased films have been made widespread across the UK and Europe thanks to the VCD format.
How Can I View a VCD?
VCDs can be viewed either with a standalone VCD player, a DVD player capable of playing the VCD format or a PC with the appropriate software. For Win9x and NT there are a number of programs that will play high quality VCDs such as Active Movie (MS), Xing, Jiao MpegPlayer, MoviePlay, VCD Powerplay etc. Playstation VCD adaptors are now available which, attached to the console, will allow you to play VCDs on your PSX console! This means that you can hook up your Playstation to a nice big TV and watch the latest films as if you are in a cinema!
What is the Video Quality Like?
A genuine VCD has very good quality and when played through a TV (rather than a PC moniter) the quality is very good. It is basically the same quality picture as a VHS tape (many would argue about that, but it is). The sound quality is much better than a VHS tape as it is CD quality. There is however a huge market for bootlegged VCDs in the east, these VCDs contain the latest movies that are still playing in cinemas and are highly illegal.
There are a range of quality with these and these terms are used:
CAM - This type of VCD was recorded by someone in a cinema with a camcorder and the audience can be heard! The picture quality is usually OK but the sound is mostly very bad and hard to make out speech.
Telesync - These are also recorded ina cinema but usually on an expensive camera and they should have a seperate audio source (so the audience cannot be heard), these are generally very good quality and highly watchable.
Screener - A Screener is usually recorded form a promotional video tape which is sent to censors and film critics etc.. The quality is usually as good as a commercial VCD, some times a copyright message appears on the screen.
Work-Print - Each frame of the film is copied from celluloid (or another source), these are sometimes incomplete movies. The sound is usually perfect and the visual quality can vary.
LD/DVD - VCDs with this on the cover are taken (ripped)from DVD or Laserdisc versions of the film and the quality is as good as genuine VCDs.
Are They The Same As DVDs or Laser Discs?
No, DVD uses a much much higher resouloution than VCD and the visual quality is much increased as a result. A whole film can be put on 1 DVD disc (4000-17000 Megabytes). The sound is also better because DVDs use Dolby 5.1 Digital Sound or DTS (Digital Theatre Sound). The quality is not as good as Laserdisc either because LDs can hold lots more DATA but LDs are huge discs and need to be turned over half way through the film.
Are VCDs Legal?
This depends on what you are doing with the VCD in question. The VCD specification is actually a professional standard that many people use for their own purpose. This can range from anything between home movies to company presentations. VCDs only become illegal if you buy, sell or trade illegitimate copies with other people. This is treated exactly the same as normal software piracy, with the copyright holders legally able to sue you for breach of copyright.
Details about Super VCD
Super VCD allows a full length movie to be stored on two or three discs. Multi-disc players can give near-seamless, uninterrupted playback of movies using this format. The use of MPEG-2 VBR (variable bit rate) video encoding, as used for DVD-Video, gives improved quality without an unacceptable reduction in playing time.
VCD can deliver up to 2 times sharper video images than the previous VCD standard. SVCD specifies MPEG2 video at 576x480 resolution, almost four times the MPEG1 resolution specified in VCD.
SVCD is backward compatible with VCD1.1, 2.0, and Interactive VCD 3.0 formats. Furthermore, while VCD requires text to be embedded in the video, SVCD uses a dedicated text data stream. This allows graphics and text such as multi-language subtitles for movies or karaoke text to be added at any time, while eliminating artifacts common with the compressed graphics and text streams of VCD.
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