Sony?s entertainment robots Aibo play and communicate with each other at the company?s laboratory in Tokyo. The robots can express emotions such as anger, sadness and happiness in a specially developed language. (AFP)

MP3 changed the way we listen to and share music. Its ability to compress an audio file and yet retain the quality helped easy distribution of any song over the Internet and established MP3 as one of the most popular file formats.

Easy transportability led to easier sharing of music files and also raised concerns of music piracy through peer-to-peer networks like Napster and Kazaa.

Now, MPEG-4 plans to take things a few steps further.

MPEG-4

It is the latest compression standard that builds on the proven success of digital television, interactive graphics applications and interactive multimedia (like the World Wide Web).

According to MPEG Industry Forum, the non-profit organisation which promotes emerging MPEG standards, MPEG-4 brings these areas together to develop a standard that enables the production of content with greater reusability and flexibility than is possible today with individual technologies.

MPEG-4 also scales to transport media at any data rate ? from delivery over dial-up modems to high-bandwidth networks ? and across devices, from satellite television to wireless gadgets.

Extension

The normal extension for MPEG-4 media is ?.mp4?. The difference between MP3 and MP4, however, is that while MP3 (or MPEG-1 Audio Layer 3) is exclusively used for compressing audio, MP4 supports audio, video, pictures and more.

The recommended extension for MPEG-4 audio files, however, is ?.m4a?. For distinction, MP4 files may or may not contain MPEG-4 audio, but an M4A file will always contain MPEG-4 audio. MP4 can be used for MPEG-4 video files, combined video and audio files, or just MPEG-4 audio.

History

MPEG-4 was defined by the Moving Picture Experts Group (MPEG), the working group within the International Organisation for Standardisation (ISO) that came up with a family of standards used for coding audio-visual information (like movies, video, music) in a digital compressed format.

The body specified the standards MPEG-1 and MPEG-2. While MPEG-1 contributed to the development of the CD-ROM industry, MPEG-2 helped the DVD development cause.

MPEG-4 was also the result of an international effort involving hundreds of researchers and engineers. The MPEG committee designed MPEG-4 to be a single standard covering the entire digital media workflow ? from capture, authoring, and editing to encoding, distribution, playback, and archiving.

MPEG-4 was finalised in 1998 and acquired a formal International Standard Status in 2000. Some work, on extensions in specific domains, is still in progress.

MPEG-4 and Apple

Apple played a key role in the development of MPEG-4. Apple?s QuickTime file format was adopted as the basis for the MPEG-4 file format, but later underwent many changes to support all the functionality of MPEG-4.

Apple also popularised the ?.m4a? extension by using the file extension in its iTunes software and iPod music players to distinguish between MPEG-4 video and audio files.

To ensure that the MPEG-4 media stream created using one company?s product runs on another vendor?s player, Apple, together with Cisco, IBM, Kasenna, Philips and Sun Microsystems, formed the Internet Streaming Media Alliance (ISMA). The ISMA defines the profiles that companies implement to ensure interoperability.

Now, the big question is whether MP4 will actually be able to deliver on the promises and become as popular a file format as MP3.