Motion vectors See MPEG-2

MP3

A high-performance, perceptual audio compression coding scheme which exploits the properties of the human ear and brain while trying to maintain perceived sound quality. MPEG-1 and 2 define a family of three audio coding systems of increasing complexity and performance – Layer-1, Layer-2 and Layer-3. MP3 is shorthand for Layer-3 coding. MPEG defines the bitstream and the decoder but, to allow for future improvements, not an encoder. MP3 is claimed to achieve ‘CD quality’ at 128-112 kb/s – a compression of between 10 and 12:1. See also: Auditory masking Website: www.mp3-tech.org

MP@ML, MP@HL See MPEG-2

MPEG – general Moving Picture Experts Group. This a working group of ISO/IEC for the development of international standards for compression, decompression, processing, and coded representation of moving pictures, audio and their combination. It has also extended into metadata. Websites: www. chiariglione.org/mpeg www.mpeg.org www.mpegif.org

MPEG-1

The standard on which such products as Video CD and MP3 are based. MPEG-2

The standard on which such products as Digital Television set top boxes and DVD are based.

MPEG-4

The standard for multimedia for the fixed and mobile web. MPEG- 4 absorbs many of the features of MPEG-1 and 2 and other related standards, adding new features such as (extended) VRML support for 3D rendering, object-oriented composite files (including audio, video and VRML objects), support for externally-specified Digital Rights Management and various types of interactivity. AAC (Advanced Audio Coding) was standardized as an adjunct to MPEG-2 (as Part 7) before MPEG-4 was issued. MPEG-4 is still a developing standard and is divided into a number of parts. Companies promoting MPEG-4 compatibility do not always clearly state which “part” level compatibility they are referring to. The key parts to be aware of are MPEG-4 part 2 (including Advanced Simple Profile, used by codecs such as DivX, Xvid, Nero Digital and 3ivx and by Quicktime 6) and MPEG-4 part 10 (MPEG-4 AVC/H.264 or Advanced Video Coding, used by the x264 encoder, by Nero Digital AVC, by Quicktime 7, and by high-definition video media like Blu-ray Disc).

MPEG-7

The standard for description and search of audio and visual content. MPEG-7 is intended to provide complementary functionality to the previous MPEG standards, representing information about the content, not the content itself

MPEG-21

The MPEG-21 standard aims at defining an open framework for multimedia applications. MPEG-21 is ratified in the standards ISO/

IEC 21000 - Multimedia framework (MPEG-21). Specifically, MPEG-21 defines a “Rights Expression Language” standard as means of sharing digital rights/ permissions/ restrictions for digital content from content creator to content consumer. As an XML -based standard, MPEG-21 is designed to communicate machine-readable license information and do so in a “ubiquitous, unambiguous and secure” manner. It is hoped by the industry that the standard will bring an end to illicit file-sharing of content.

MPEG-A

The standard providing application-specific formats by integrating multiple MPEG technologies;

MPEG-B

A collection of Systems specific standards MPEG-C

A collection of Video specific standards MPEG-D

A collection of Audio specific standards MPEG-E

A standard (M3W) providing support to download and execution of multimedia applications

MPEG-M

A standard (MXM) for packaging and reusability of MPEG technologies MPEG-U

A standard for rich-media user interface MPEG-V

A standard for interchange with virtual worlds

MPEG-IMX See IMX

MSB See Digit

MTBF Mean Time Between Failure. A statistical assessment of the average time taken for a unit to fail – a measure of predicted reliability. The MTBF of a piece of equipment is dependent on the reliability of each of its components. Generally the more components the lower the MTBF, so packing more into one integrated circuit can reduce the component count and increase the reliability. Modern digital components are highly reliable. Even complex electro-mechanical assemblies such as hard disk drives now offer MTBFs of up to a million hours – some 110 years! Note this does not mean a drive has been run for 110 years and failed just once, nor that it is expected to run for this period without failure, but it does indicate the average failure rate of many components of the same type.

MTF

The Modulation Transfer Function is a measure of spatial resolving power. It can refer to a medium,such as film, ora lens, orany part of the scene- to-screen chain. It is akin to frequency response in electronic images. To

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GLOSSARY OF TERMS