Although some of us are knowledgeable about DVD / Blu-ray systems, many are left baffled by the more techie terminology. Pick up your manual, or look online to answer specific questions - you'll be bombarded by odd words and acronyms.
To make matters clear, here are some important DVD and Blu-ray related terminology and their definitions. As you may note, the more you learn, the more you'll need to know...
For a general overview of DVD regions and unlock codes, please check our FAQ.
BD-25 - A Blu-ray disc with a 25GB capacity.
BD-50 - A Blu-ray disc with a 50GB capacity.
BD-9 - A red laser DVD with BD content. A capacity of 9GB.
BDA - The Blu-ray Disc format was developed by the Blu-ray Disc Association or BDA; a consortium of the world's leading consumer electronics, personal computer and media manufacturers.
BD Live - BD-Live offers network connectivity to the list of mandatory functions and increases local storage capability.
BD-R - (Blu-Ray Disc-Recordable) See Blu-ray
Bitstream - A method way of transmitting information from one space to another. Bitstream data transmission sends compressed information (data that has been previously ‘packaged’ to an audio receiver) to a receiver that then de-codes the data before it can be read and played as sound.
Blu-ray - Derived from the blue-violet laser used to read and write to this format of disc. Because of its shorter wavelength (405 nm), substantially more data can be stored on a Blu-ray Disc than on the DVD format, which uses a red (650 nm) laser. A single layer Blu-ray Disc can store 25 gigabytes (GB), over five times the size of a single layer DVD at 4.7 GB. A dual layer Blu-ray Disc can store 50 GB, almost 6 times the size of a dual layer DVD at 8.5 GB.
Bonus View - Described picture-in-picture content played during the main feature. Also known as IME (in-movie experience). Blu-ray players with Profile 1.1 specs and above can play Bonus View features.
Coffee Book - A style of Blu-ray disc designed by Warner Bros. It resembles a hardcover book and contains a limited number of pages describing the release, acting as a virtual storage box for Blu-ray discs.
Compression - Takes a large amount of information and re-writes it so that the new data takes up less space. This is known as “compressing” the data. Before the data can be used again, it must be decompressed or “decoded”. Some processes allow for exact copies of the original audio to be produced (Lossless), others do not produce exact copies of the original data and therefore some information is lost (Lossy)
CD - Compact Disc
CD-R - (Compact Disc-Recordable) is a variation of the Compact Disc invented by Philips and Sony. CD-R is a Write Once, Read Many optical medium (though the whole disk does not have to be entirely written in the same session) and retains a high level of compatibility with standard CD readers (unlike CD-RW which can be rewritten but has much lower compatibility and the discs are considerably more expensive).
CD-RW - (Compact Disc ReWritable) is a rewritable optical disc format. Known as CD-Erasable (CD-E) during its development, CD-RW was introduced in 1997, and was preceded by the never officially released CD-MO in 1988.
Durabis - The brand name for the clear scratch-resistant polymer disc coating developed by the TDK corporation.
DVD-Audio - Also known as DVDA is
a digital format for delivering very
high-fidelity audio content on a DVD
DVD - Digital Versatile Disc (formerly Digital Video Disc).
DVD Code - The sequence of button presses on a DVD player's handset controller that makes it Region Free. This can also be achieved using the buttons on the face of the DVD player itself.
DVD Codes - As above. Find yourself a good unlock database and you're away!
DVD Forum - A membership organization devoted to defining DVD standards for read-only, rewritable, write-once, video and audio use. Members participate in working groups to develop new standards. Based in Tokyo, Japan and founded in late 1995 as the DVD Consortium, it was renamed the DVD Forum in 1997. "Minus RW" and "Minus R" are commonly used to refer to the DVD-RW and DVD-R formats of the DVD Forum compared to the DVD+RW Alliance's DVD+RW and DVD+R.
DVD Multi - A specification from the DVD Forum that certifies DVD drives for media compatibility. Drives with the DVD Multi logo can read and write DVD-RAM, DVD-RW and DVD-R discs as well as read DVD-Video and DVD-ROM. DVD Multi drives may also be able to play DVD-Audio discs.
DVD Multi-Region - When a player can play DVDs from any region, it is regarded as 'multi-region' enabled.
DVD Player - A stand-alone device that plays DVDs. It contains a DVD drive and the electronics to decode the digital video. The device may play only manufactured DVDs, or it may be able to play DVD-R, DVD-RW and DVD+RW discs. DVD players are cabled to a TV or home theatre system for display.
DVD-RAM (DVD–Random Access Memory)
is a disc specification presented in
1996 by the DVD Forum, which specifies
rewritable DVD-RAM media and the
appropriate DVD writers. DVD-RAM media
have been used in computers as well as
camcorders and personal video recorders
since 1998. The direct successor of this
format will be HD DVD-RAM.
DVD Recorder - An optical disc recorder that records video onto blank writable DVD media. Such devices are available as either installable drives for computers or as standalone components for use in studios or home theater systems.
DVD-R - A DVD recordable format. A DVD-R has a larger storage capacity than its optical predecessor, the 700 MB CD-R, typically storing 4.71 GB (or 4.382 GiB), although the capacity of the original standard developed by Pioneer was 3.95 GB (3.68 GiB). Pioneer has also developed an 8.54 GB dual layer version, which appeared on the market in 2005. Data on a DVD-R cannot be changed, whereas a DVD-RW (DVD-rewritable) can be rewritten multiple (1000+) times. DVD-R(W) is one of three competing industry standard DVD recordable formats; the others are DVD+R(W) and DVD-RAM.
DVD Region Free - A term denoting a multi-region enabled DVD system.
DVD Remote Codes - The handset
sequence described to activate a DVD
DVD Unlock - The end product of using a handset sequence - an unlocked, Multi-Region DVD player. An unlock can be referred to loosely as a DVD code.
DVD-RW - A rewritable optical disc with equal storage capacity to a DVD-R, typically 4.7 GB. The format was developed by Pioneer in November 1999 and has been approved by the DVD Forum. Unlike DVD-RAM, it is playable in about 75% of conventional DVD players.
DVD+RW - The name of a standard for optical discs: one of several types of DVD, which hold up to about 4.7GB per disc (interpreted as approximately 4.7 × 109 bytes; actually 2295104 sectors of 2048 bytes each) and are used for storing films, music or other data.
DVD+RW Alliance - An industry consortium devoted to promoting rewritable and write-once DVD standards. Founded in 1997 by HP, Philips, Sony and others, it developed the DVD+RW specification as an evolution of the CD-RW format. The Alliance was formed to provide a format that was more compatible with consumer DVD players than the DVD-RAM format that was being developed by the DVD Forum at that time. "Plus RW" and "Plus R" are commonly used to refer to the DVD+RW and DVD+R formats of the Alliance compared to the DVD Forum's DVD-RW and DVD-R.
DVR - Digital Video Recorder
Hack - A clever or quick fix to a computer program or technological problem. The surface implication was a casual attempt to fix the problem, but the deeper meaning was something more clever and thus impressive. In our case it means safely making a DVD player Region Free using DVD codes.
HDCP - High Definition Content Protection. A system used to ensure that content cannot be copied from one source to another. All devices (DVD Player, TV etc) must support this, or the High Definition signal will be downgraded to VHS Quality.
HDMI - HDMI or High-Definition Multimedia Interface is an all-digital interface capable of transmitting uncompressed streams of data. HDMI provides an interface between any compatible digital source, such as a DVD player, a PC or video game system.
- (High Definition Multimedia Interface)
is currently the best, most advanced way
to watch high definition content.
HD-DVD - The failed successor to the standard DVD format, derived from the same underlying technologies. It can store about 3 1/2 times as much data as its predecessor (Maximum capacity: 30 GB instead of 8.5 GB). A 51 GB triple-layer preliminary spec has been approved. However, no movies are currently scheduled for this disc type.
HD DVD-R - The writable disc variant of HD DVD, and is available with a single-layer capacity of 15 GB or dual-layer capacity of 30 GB. Currently, HD DVD-R has slower write speeds than the competing BD-R format (1–2x vs. 1–4x) and lower storage capacity.
HD DVD-RAM - The proposed successor to DVD-RAM for random access on optical media using phase-change principals. HD DVD-RAM will hold 20 gigabytes per layer instead of 15 gigabytes for HD DVD-R because of differences in recording methods used, yielding a higher density disc.
IAR - Intended Aspect Ratio. Where as OAR, original aspect ratio, can be described in various contexts - anything from an original camera negative aspect ratio, to how the digital material was originally shown.
Letterbox - If original aspect ratio of a film does not match the ratio of the display device it results in black bars above and below the TV screen. This maintains the film in a condition as it was intended to be seen.
Lossless - Refers to audio that has been reproduced from the original source without having lost any information. Lost information results in a less-than-perfect reproduction of the audio track. Not all players are capable of decoding/transmitting every type of compressed data.
Lossy - Refers to audio that is not an exact reproduction of the original. During the recording/compression process, information may have been lost, resulting in a loss of quality/depth/ or richness of sound. Not all players are capable of decoding/transmitting every type of compressed data.
MAR - Modified Aspect Ratio. Used to
convey instances when the intended
aspect ratio of the material has been
altered or modified from its intended
composition without the express
permission and oversight of its
Multi-Region - When a player can play DVDs from any region, it is regarded as 'multi-region' enabled.
OAR - Original Aspect Ratio.
PCM - “Pulse Code Modulation”. A specific way of transmitting digital sound information from one place to another. The PCM ‘style’ of data transmission sends the data “uncompressed”. This means that when it is sent from the data source (a Blu-ray disc, CD, etc.) to a piece of audio equipment – it can be instantly ‘read’ and played.
Pillarbox - When the original aspect ratio of a film does not match the aspect ratio of the display device it is viewed with resulting in black bars or pillars on the sides of the TV screen. This maintains the film as it was intended to be seen. Examples: Old films with a 4:3 or 1.37:1 aspect ratio will result in a pillarbox effect.
Posterization - Occurs when the
colour depth, sometimes called bit
depth, is insufficient to accurately
sample a continuous gradation of colour
tone. As a result, a continuous gradient
appears as a series of discrete steps or
bands of colour — hence the name. When
discussing fixed pixel displays, such as
LCD and plasma televisions, this effect
is referred to as false contouring.
Region Free - A DVD player able to play DVDs from any region in the world. See our our unlocks page to DIY.
Unblock - A DVD unblock or unblocker
solution is the same as a multi-region
unlock - just under a different name.
If you have any DVD additions you'd like to see on this page, or have further questions you need answered, e-mail us at firstname.lastname@example.org