MPEG-1(cont.) <ul><li>Part 3 of the MPEG-1 standard covers audio and is defined in ISO/IEC-11172-3 </li><ul><li>Layer I ： Layer I uses a smaller 384-sample frame size for very low delay, and finer resolution.
Layer II ： a lossy audio format designed to provide high quality at about 192 kbit/s for stereo sound
Layer III/MP3 ： a lossy audio format designed to provide acceptable quality at about 64 kbit/s for monaural audio over single-channel (BRI) ISDN links, and 128 kbit/s for stereo sound. </li></ul></ul>
MPEG-1(cont.) <ul><li>Part 4 of the MPEG-1 standard covers conformance testing, and is defined in ISO/IEC-11172-4.
Part 5 of the MPEG-1 standard includes reference software, and is defined in ISO/IEC-11172-5.
Note that Mp3 NOT 「 MEPG3 」 ,means MPEG1 Layer 3 </li></ul>
MPEG-2 <ul><li>a standard for "the generic coding of moving pictures and associated audio information".
a combination of </li><ul><li>lossy video compression
lossy audio data compression </li></ul><li>permit storage and transmission of movies using currently available storage media and transmission bandwidth. </li></ul>
MPEG-2(cont.) <ul><li>MPEG-2 is widely used as the format of digital television signals that are broadcast by terrestrial (over-the-air), cable, and direct broadcast satellite TV systems.
specifies the format of movies and other programs that are distributed on DVD and similar discs.
MPEG-2 evolved out of the shortcomings of MPEG-1. </li></ul>
MPEG-4 <ul><li>absorbs many of the features of MPEG-1 and MPEG-2 and other related standards
adding new features such as </li><ul><li>(extended) VRML support for 3D rendering
object-oriented composite files (including audio, video and VRML objects)
support for externally-specified Digital Rights Management
various types of interactivity </li></ul></ul>
MPEG-4(cont.) <ul><li>MPEG-4 was aimed primarily at low bit-rate video communications
left to individual developers to decide whether to implement the features of MPEG-4. </li></ul>
formally called Multimedia Content Description Interface.
The combination of MPEG-4 and MPEG-7 has been referred to as MPEG-47. </li></ul>
MPEG-7(cont.) <ul><li>It was designed to standardize: </li><ul><li>a set of Description Schemes (short DS in the standard) and Descriptors (short D in the standard)
a language to specify these schemes, called the Description Definition Language (short DDL in the standard)
a scheme for coding the description </li></ul></ul>
MPEG-21 <ul><li>aims at defining an open framework for multimedia applications.
MPEG-21 is ratified in the standard ISO/IEC 21000
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. </li></ul>
MPEG-21(cont.) <ul><li>MPEG-21 is based on two essential concepts </li><ul><li>the definition of a fundamental unit of distribution
the definition of a fundamental unit of transaction(Digital Item ─ the concept of users interacting with them. </li></ul><li>MPEG-21 provides a framework in which one user interacts with another one, and the object of that interaction is a Digital Item. </li></ul>