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. It also specifies the format of movies and other programs that are distributed on DVD and similar disks. As such, TV stations, TV receivers, DVD players, and other equipment are often designed to this standard. MPEG-2 was the second of several standards developed by the Moving Pictures Expert Group (MPEG) and is an international standard (ISO/IEC 13818). Parts 1 and 2 of MPEG-2 were developed in a joint collaborative team with ITU-T, and they have a respective catalog number in the ITU-T Recommendation Series.
MPEG-4 provides a series of technologies for developers, for various service-providers and for end users.
MPEG-4 enables different developers to create objects possessing better abilities of adaptability and flexibility to improve the quality of such services and technologies as digital television, animation graphics, World Wide Web and their extensions. This standard enables developers to control their content better and to fight more effectively against copyright violations.
Various network providers can use MPEG-4 for data transparency. With the help of standard procedures such data can be interpreted and transformed into various signals compatible with any available network.
The MPEG-4 format provides the end users with a wide range of interaction with various animated objects.
Standardized Digital Rights Management signaling, otherwise known in the MPEG community as Intellectual Property Management and Protection (IPMP).
The MPEG-4 format can perform various functions, among which might be the following:
Multiplexes and synchronizes data, associated with media objects, in such a way that they could be transported further via network channels.
Interaction with the audio-visual scene, which is formed on the side of the receiver.
DivX is a brand name of products created by DivX, Inc. (formerly DivXNetworks, Inc.), including the DivX Codec which has become popular due to its ability to compress lengthy video segments into small sizes while maintaining relatively high visual quality. The DivX codec uses lossy MPEG-4 Part 2 compression, also known as MPEG-4 ASP, where quality is balanced against file size for utility. It is one of several codecs commonly associated with "ripping", where audio and video multimedia are transferred to a hard disk and transcoded. Many newer "DivX Certified" DVD players are able to play DivX encoded movies, although the Qpel and global motion compensation features are often omitted to reduce processing requirements. They are also excluded from the base DivX encoding profiles for compatibility reasons.