Video CD

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Video CD
Image:VCDlogo.svg
Image:Compact disc.svg
A standard pressed compact disc
Media type:optical disc
Encoding:MPEG-1 video + audio
Capacity:up to 800 MiB
Read mechanism:780 nm wavelength semiconductor laser
Developed by:Sony & Philips
Usage:audio and data storage
VCD redirects here. For other uses, see VCD (disambiguation)
This article is about the all-digital 'Video CD' format. For the earlier (and less successful) analog/digital hybrid, see CD Video.

Video CD (aka VCD, View CD, Compact Disc digital video) is a standard digital format for storing video on a Compact Disc. VCDs are playable in dedicated VCD players, most modern DVD-Video players, and some video game consoles.

The VCD standard was created in 1993 by Sony, Philips, Matsushita, and JVC and is referred to as the White Book standard.

Contents

[edit] Technical specifications

[edit] Video

Overall picture quality is intended to be comparable to VHS video, though VHS has twice as many scanlines (approximately 480 NTSC and 580 PAL) and therefore double the vertical resolution. Poorly compressed video in VCD tends to be of lower quality than VHS video, but VCD exhibits block artifacts rather than analog noise, which may be preferable.

352 horizontal pixels was chosen because it approximates the resolution of an analog VHS tape, assuming a 3 MHz bandwidth. In addition, 352 equates to a DVD resolution of 704 divided by 2, making it easy to convert from one standard to another.

VCD video is mostly compatible with the DVD-Video standard, except for any video encoded at 23.976 frames per second. DVD-Video requires all video to be encoded at either 25 or 29.97 frames per second, and 23.976 frames per second video requires up-conversion to 29.97 frames per second through the use of telecine flags in the video.

[edit] Audio

As with most CD-based video formats, VCD audio is incompatible with the DVD-Video standard due to the difference in frequency; DVDs require 48 kHz, whereas VCDs use 44.1 kHz.

[edit] Other information

Video CDs are authored (or "burned") using the Mode 2/XA format, allowing roughly 800 megabytes of VCD data to be stored on one 80 minute CD (versus 700 megabytes when using Mode 1). This, combined with the net bitrate of VCD video and audio, means that almost exactly 80 minutes of VCD content can be stored on an 80 minute CD, 74 minutes of VCD content on a 74 minute CD, and so on. This was done in part to ensure compatibility with existing CD drive technology, specifically the earliest "1x speed" CD drives.

[edit] Similar formats

[edit] XVCD

"XVCD" (eXtended Video CD) is the name given to just about any format that stores MPEG-1 video on a compact disc in mode 2, but does not meet the VCD standard. Colloquially, XVCD is generally accepted to mean MPEG-1 video, VCD resolution, and a 1-CD datasize for a video file.

A normal VCD is encoded to MPEG-1 at a constant bit rate (CBR); i.e. all scenes are encoded with a standard 1150 kbit/s videostream, independent of the content. Whether it is a fast, movement-rich scene or a mostly-static, fixed-image scene, the encoder must output data at exactly the same rate. While the video on an XVCD is typically encoded with a variable bit rate (VBR); i.e. the bit rate for fast scenes can be raised to approximately 2000 kbit/s for a short time, and simple scenes may use as little as 300 kbit/s.

To further reduce the required video bit rate without significantly reducing quality, a different MPEG-1 quantization matrix is sometimes used, as well as increasing the size of the GOP (Group OF Pictures). The bit rate of the MP2 audio can also be reduced from 224kbit/s to save further space. These changes can be advantageous for those who want to maximize the video quality of their XVCDs, or for those who wish to fit a longer feature, perhaps up to 2 hours in length, on only one CD with a reasonable level of quality.

By close compliance (here “variable bit rate”) to the SVCD standard most DVD players can play XVCDs in the VCD resolution (352x288 PAL and/or 352x240 NTSC). Historically this extension of the format comes from Asia, in order to store and show complete feature films on the simplest video players using CDs, without incurring DVD licensing fees.

[edit] KVCD

There are further variants of XVCD (such as KVCD) that use larger resolutions than 352 × 288, but are essentially only playable by a very small number of DVD players, as well as computers with CD-ROM drives. Their development began with the wide availability of cheap DVD players in Asia, which were not only able to play CD-R discs, but for the first time could show video CDs, MP3, data and pictures burned to CD. One of the first multi-format players appeared in the trade was the Yamakawa AVPhile 713/715[citation needed]. The equipment was predominantly constructed from existing PC components, and not very strict about the format of VCDs, while it would not play recorded DVDs.

[edit] DVCD

"DVCD" or Double VCD is a method designed to squeeze the most out of a CD. A non-standard CD is overburned to include up to 100 minutes of video. This format is seen only in China (although such titles can be found outside China, they're extremely rare), and the DVCDs are playable on many DVD or VCD players. However, some CD-ROM drives and players have problems reading these CDs, mostly because the groove spacing is outside specifications and the laser servo is unable to track it.


[edit] Others

Other popular VCD variants include CVCD (a Spanish XVCD), and SXVCD (a VCD but with VBR MPEG-2). There is also SKVCD (or KSVCD) which does much the same thing as KVCD, but uses MPEG-2 and adds some luxuries such as multiple audio streams and chapters. Some of the more recent and flexible standalone players support (K)SVCD, as the format has been endorsed by Philips[citation needed], the custodian of all the CD standards.

[edit] Challenges

The largest hurdle[citation needed] was the refusal of the common CD recording programs of the day to write non-conforming MPEG-1 video CD streams to disc. They would instead reject them directly, and display an error message. A lengthy search of the CD recording programs available on the market succeeded when it was found that exchanging a certain older DLL of the CD burning program NTI CDMaker[citation needed] would overcoming this limitation, and allow recording of non-standard video CD formats.

This solution for production of a XVCDs was found after long test runs in the spring of 2000 on the DVDBoard.de public forum. For the first time, the format was given the designation "XVCD" (eXtended video CD). From there, methods of producing an XVCD with better image quality and higher data rate soon spread around the world. Manufacturers soon followed, publishing updated CD recording software that allowed the creation of XVCDs, offering devices that would play the non-standard XVCDs, and publishing technical periodicals that offered guidance for the production of such CDs at home.

[edit] Decline

However, many players could not handle the non-standard XVCD format. As the higher resolution (MPEG-2 based) SVCD format gained in popularity, and even higher resolution DivX (MPEG-4 ASP) encoded AVI files became favored, XVCD quickly declined in popularity. More recently, the falling price, and widespread availability of home DVD recorders for home users has largely eliminated the need for the XVCD format.

[edit] Adoption

The neutrality of this section is disputed.
Please see the discussion on the talk page.
This section has been tagged since December 2007.

While never gaining a foothold[citation needed] in the United States or Europe, commercial VCDs are very popular[citation needed] throughout Asia (except Japan) because of the low price of the players, their tolerance of high humidity (a notable problem for VCRs), and the lower-cost media. Ease of duplication and the negligible cost of the media gave rise to widespread unauthorized copying in these areas.

The advent of recordable CDs, inexpensive recorders, and compatible DVD players spurred VCD acceptance in the US in the late 1990s and early 2000s[citation needed]. However, DVD burners and DVD-Video recorders were available by that time, and equipment and media costs for making DVD-Video fell rapidly. DVD-Video, with its longer run time and much higher quality, quickly overshadowed VCD. In addition many DVD players made before 2003-2004 could not read recordable (CD-R) media, and this limited the compatibility of VCD. Almost every modern stand-alone DVD-Video player can play VideoCDs burned on recordable media.

Many commercial Video CDs of blockbuster Hollywood, Bollywood, Manilawood and other Asian movies and television series are not widely available in the Western countries[citation needed]; however, they are available in certain ethnic communities and several commercial web sites (although quality and authenticity may sometimes be questionable). These VCDs are often produced and sold in Asian countries such as Pakistan, Hong Kong, India, Mainland China, Thailand, Malaysia and the Philippines. In many Asian countries, major Hollywood studios (and Asian home video distributors) have licensed companies to officially produce and distribute the VCDs, such as MCA Home Video in Pakistan, ERA of Hong Kong or Sunny Video in Malaysia, Excel Home Videos in India, Berjaya-HVN and InnoForm Media in both Malaysia and Singapore, as well as VIVA Video, Magnavision, and The Video to C in the Philippines. Legal Video CDs can often be found in established video stores and major book outlets in most Asian countries.

Around 2003–2006, VCDs were given away by Greek newspapers to boost declining sales[citation needed]. Because of this documentaries, films and even soft porn VCDs became very common in Greece[citation needed].

VCD's became popular in Latin America around 2002-2004, as they were cheaper and easier to copy than DVD's, although they're now slowly being replaced as DVD's prices drop.

Due to relatively small storage capacity, feature-length films sold on VCD are usually divided into two or three discs and television series may come in a box set package with multiple discs. In both cases, most films run at roughly 60 minutes per VCD, before viewers are prompted to change discs. However, there are also VCD players that have built-in CD changers in them which provide several discs to be queued. Subtitles are found on many Asian VCDs, and unlike DVDs, cannot be removed.

VCD is gradually being replaced by DVD, which offers most of the same advantages to Asian buyers as VCD[citation needed], as well as a much better quality picture (higher resolution with less digital compression artifacts) and sound (often in Dolby Digital and/or DTS), due to its larger storage capacity.

VCD does however have a few points in its favor:

  • Like VHS and unlike DVD-Video, the VCD format has no region coding. Many VCD players are capable of compensating for the different frame rate and pixel count between NTSC and PAL (plus SECAM) TV systems, which means that discs can be played on any compatible machine worldwide.
  • Some titles available on VCD may not be available on DVD and/or VHS in the prospective buyer's region.
  • VCD is also a very popular format for karaoke in East Asia, where picture quality concern is not paramount.

These factors may ensure a steady market for VCDs for many years to come[citation needed].

[edit] References

This article does not cite any references or sources. (March 2007)
Please help improve this article by adding citations to reliable sources. Unverifiable material may be challenged and removed.

[edit] See also

[edit] External links

v • d • e
Industrial & home video media
Magnetic tape
Analog

VERA (1952) • 2 inch Quadruplex videotape (1956) • 1 inch type A videotape (1965) • 1/4 inch Akai (1967) • U-matic (1969) • EIAJ-1 (1969) • Cartrivision (1972) • Video Cassette Recording (aka VCR) (1972) • V-Cord (1974) • VX (aka "The Great Time Machine") (1974) • Betamax (1975) • IVC 2 inch Helical scan (1975) - 1 inch type B videotape (1976) • 1 inch type C videotape (1976) • VHS (1976) • VK (1977) • SVR (1979) • Video 2000 (1980) • CVC (1980) • VHS-C (1982) • M (1982) • Betacam (1982) • Video8 (1985) • MII (1986) • S-VHS (1987) • Hi8 (1989) • S-VHS-C (1987) • W-VHS (1994)

Digital

D1 (1986) • D2 (1988) • D3 (1991) • D5 (1994) • Digital Betacam (1993) • DV (1995) • Digital-S (D9) (1995) • DVCPRO (1995) • DVCAM (1996) • HDCAM (1997) • DVCPRO50 (1998) • D-VHS (1998) • Digital8 (1999) • DVCPRO HD (2000) • D6 HDTV VTR (2000) • MicroMV (2001) • HDV (2003)• HDCAM SR (2003)

Optical disc
Analog

Laserdisc (1978) • Laserfilm (1984) • CD Video (1986?)

Digital

VCD (1993) • MovieCD (1995?) • DVD-Video (1995) • MiniDVD • CVD (1998) • SVCD (1998) • FMD (2000) • EVD (2003) • HVD (2004) • FVD (2005) • UMD (2005) • VMD (2006) • HD DVD (2006) • Blu-ray Disc (BD) (2006) • DMD (2006?) • AVCHD (2006) • Tapestry Media (2007) • Total Hi Def (2008) • HVD (TBA) • PH-DVD (TBA) • SVOD (TBA) • Protein-coated disc (TBA) 3D disc (TBA)

Grooved Videodiscs
Analog

Baird Television Record aka Phonovision (1927) • TeD (1974) • Capacitance Electronic Disc aka CED (1981) • VHD (1983)

cs:Video CD

de:Video-CD es:Video CD fr:Vidéo CD ko:비디오 CD id:VCD it:Video CD nl:Video-cd ja:ビデオCD no:Video CD pl:Video CD pt:VCD simple:Video CD sv:Video cd th:วีซีดี vi:VCD tr:VCD uk:Video CD zh:VCD

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