Tagged: 12cm

The diameter of the Compact Disc, and hence the diameter of most optical disc formats since that time

Fujifilm PhotoDisc CD-R (2004 – )

Launched in 2004, The Fujifilm PhotoDisc CD-R is essentially a standard CD-R disc with a black substrate layer that claims to protect the data from ultra-violet and solar radiation. It also uses a different dye (phthalocyanine rather than the usual cyanine) in the recording layer, which should offer more resistance to heat and sunlight.

Although they are reported to be very reliable, for archival purposes gold archival CD-R discs are probably better.

Despite the name, the discs can be used for any purpose that a standard CD-R can be used for, and don’t just store photos.

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MovieCD (1997 – late 1990s)

MovieCD was a CD-ROM format for video, introduced by Sirius Publishing Inc. in early 1997, that allowed people to view full-length movies on their Windows PC or laptop using a standard CD-ROM drive.

MovieCDs could be played on PCs running Windows 3.1 and Windows 95 without the need for any additional hardware or software, and the PC hardware requirements were fairly modest. The necessary software and the MotionPixels codec were on the discs themselves and installed automatically.

Each disc could hold up to 45 minutes of video, so two or sometimes three discs were necessary for longer films. The resolution was 320×236 pixels, and the format promised ‘near-TV quality’ images (though of course, the format could only be played on a PC – there were no set-top MovieCD players available).

Over 100 titles were available on the MovieCD format including anime, music concerts and feature films. It competed with Video CD and the newly launched DVD-Video, and no version of MovieCD was developed for versions of Windows beyond Windows 95. It was not a commercial success and disappeared after a few years.

Using the discs on a post-Windows 98 system can cause problems with other video and audio software.

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UHQCD (Ultimate High Quality Compact Disc) (2015 – )

UHQCD is a type of audio Compact Disc introduced by Memory-Tech in Japan in 2015, and is a development of the HQCD (High Quality Compact Disc) introduced six years previously. UHQCD discs conform to Red Book standards and are playable in any audio CD player. They don’t contain any more audio information than a standard CD, but it is claimed that a higher-quality manufacturing process and higher quality materials in the reflective layer produces higher precision audio reproduction.

A photopolymer is used instead of standard polycarbonate, since in their liquid state photopolymers achieve better replication of the pits on the CD stamper.

As of 2017, there were over 900 titles available on UHQCD.

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Blu-spec CD (2008 – )

The Blu-spec CD was introduced in 2008 by Sony, and is a Red Book-compliant audio Compact Disc, so is playable on all audio Compact Disc players. Sony launched with 60 titles on Blu-spec CD.

Its name is derived from the shorter-wavelength blue laser used to create the master copy, which is claimed to produced more precise pits to reduce distortion due to reading errors, along with a new polymer polycarbonate developed for the Blu-ray Disc.

In 2012, a newer version called Blu-spec CD2 (or BSCD2) was introduced that claimed to have a more precise cutting machine and master discs made from silicon wafers. Sony called it Phase Transition Mastering.

Due to existing limitations of Compact Disc Digital Audio, it is debatable whether Blu-spec CDs offer better sound quality as there is no extra information stored on the disc.

As of 2017, new titles are still being released on both formats.

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Minimax Compact Disc (1990s – )

Minimax Compact Discs are generally CD singles which consist of a 3-inch playing area (equivalent to the mini CD single) surrounded by an area of translucent plastic (either clear or coloured) to make them full-size Compact Discs. The playable part of the disc conforms to Red Book standards.

On a normal Compact Disc, the reflective layer would continue to the edge of the disc, even if there was not enough music to fill it.

Because of the small playing area, minimax CDs can only hold a limited playing time (about 24 minutes maximum) and so have only been used for music singles or EPs.

They are very uncommon, presumably because of the extra expense in manufacturing them over a standard 5-inch CD single, but have been used for special edition singles, in much the same way as coloured vinyl records. It could be argued that the holographic CD is a form of minimax CD, as it is also formed of a mini CD single inside a larger area of plastic containing the holographic design.

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Interactive DVD (1998 – )

Interactive DVDs (sometimes also known as DVD games, DVD Interactive or DVDi) allow the playing of games on DVD-Video players without the need for a computer or video game console, or any additional hardware (though some titles come with additional hardware such as buzzers).

The interactive DVD make use of the rudimentary interactivity features built-in to DVD-Video players that allow, for example, navigation through menus. The ability to skip to any point on the DVD instead of having to move through the video in a linear fashion as on VHS video recorders is also a major factor in making interactive DVDs practical.

The first interactive DVD game was Dragon’s Lair released in 1998, and a development of an older LaserDisc based game.

From 2001, DVD versions of board games and television quiz shows began to be released.

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Copy-protected Compact Disc (2000 – 2006)

The original specification for Compact Disc Digital Audio, known as the Red Book, did not make any provision for copy protection, and by the late 1990s millions of ripped audio tracks from Compact Discs were compressed as MP3s and shared over the internet.

The music industry did several things to try and rectify the situation, including setting up online music stores selling music through a subscription model, and the Recording Industry Association of America also prosecuted over 20,000 individuals they accused of sharing pirated MP3s.

Starting around 2000, the music industry also began to put copy-protection onto audio Compact Discs. Companies such as EMI, Sony, BMG, and for a time Warner used copy protection as a means to prevent ripping of audio tracks onto a computer.

Since the discs were non-compliant with the Red Book standard, they were not supposed to display the Compact Disc Digital Audio logo on either the disc or inside the jewel case. There was also a consumer outcry against the disks as they prevented tracks from being copied to the purchaser’s personal audio devices, and some CD players such as those in cars would not play the disks (since these sometimes used some CD-ROM components, especially if they were intended to play disks containing MP3 or other types of compressed files).

In 2005, it was discovered that Sony BMG were using a type of copy protection called Extended Copy Protection (XCP) which installed a rootkit on a user’s computer. This sparked a scandal as it could be used by malware, and Sony announced a recall of disks using XCP and suspended its use.

EMI was the last major label to abandon copy protection in 2006.

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Shaped Compact Disc (1996 – )

Shaped Compact Discs first appeared in the mid-1990s, the first being The Flaming Lips Compact Disc single entitled ‘This Here Giraffe’ released in 1996 on a 8-pointed star-shaped disc.

The most common form of shaped Compact Disc is the business card sized CD-ROM introduced in 1998, but shaped CDs can come in a variety of shapes. Generally, Compact Disc audio discs can be symmetric or asymmetric, whereas shaped CD-ROMs are generally symmetrical so they do not cause vibrations in high-speed CD-ROM drives.

Shaped CDs contain less audio or data than standard 12cm discs, and may not work in all drives.

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LightScribe (2004 – 2013)

LightScribe was not a format as such, but a technology introduced by Hewlett-Packard in 2004 that allowed optical drives to laser-etch labels onto compatible media.

As well as a compatible LightScribe enabled drive, LightScribe drivers and suitable disc-burning software that supported LightScribe was required. Finally, a LightScribe compatible disc was needed. After burning data to the disc, the disc is turned over so the label side is face down, and the same laser that burnt data is used to etch the reactive dye coating of the disc.

LightScribe-compatible discs came in the form of CD-R, CD-RW, DVD-R, DVD-RW, DVD+R and DVD+RW. No Blu-ray discs were LightScribe compatible.

The LightScribe technology could only etch in monochrome, and it was possible for the design to fade over time, especially if the disk was exposed to direct sunlight. Etching a disc took a considerable amount of time; up to 30 minutes for a high-contrast image.

As of 2013, the technology was no longer promoted by Hewlett-Packard, but it is possible to obtain the software from elsewhere. Drive manufactures have now ceased making LightScribe enabled optical drives (optical drives in computers are under threat in general).

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Enhanced CD (1994 – )

An enhanced CD (or ECD) is a Compact Disc that contains both audio content playable on a standard CD audio player, and multimedia content playable on a computer CD-ROM.

Introduced in 1994, the idea behind enhanced CDs was to offer the music buyer some extra bonus features using space on the disc that was unfilled by the music. This might take the form of music videos (similar to the earlier idea of CD Video), interviews, wallpapers, pictures, lyrics, or links to an artists website.

Rather confusingly, there were three different ways on combining the different content on the disc. Prior to 1996, enhanced CDs were created in one of two ways. One was to have the multimedia content in the first track, but this meant that track 1 needed to be skipped when played in a standard CD audio player or else the multimedia track could cause an unpleasant noise to be heard. A subsequent solution was to have the multimedia content in the pre-gap before track 1 (rather like the way a CD-i Ready disc worked). Both of these methods were known as ‘mixed-mode’, combining Red Book Digital Audio and Yellow Book CD-ROM information in a single ‘session’ on the same disc.

To get around the problems of mixed-mode discs, Philips and Sony released the Blue Book standards in 1995, and worked with Apple, Microsoft and the Recording Industry Association of America (RIAA) to develop them. This new standard specified multisession technology that used two sessions on the disc, the first one containing audio tracks, and the second one containing data that is invisible to CD audio players. In 1996, most enhanced CDs used mixed-mode with the multimedia in the pre-gap, but by 1997 most were using Blue Book standards. The only downside to the newer multisession technology was that CD-ROM drives made before 1996 might not recognise them if they were not multisession capable.

Enhanced CDs can usually be recognised the official ‘Enhanced CD’ logo recommended by the RIAA. They may also have the CD EXTRA logo (previously known as CD Plus), which was trademarked by Sony for use on Blue Book discs.

Later technologies like DVD-Audio or DualDisc tried to perform the same function of offering the music album with bonus material such as videos, but later albums often came instead with the videos on a separate DVD-Video.

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