ISO/IEC 14496 is intended to be generic in the sense that it serves a wide range of applications, bitrates,
resolutions, qualities and services. Furthermore, it allows a number of modes of coding of both natural and
synthetic video in a manner facilitating access to individual objects in images or video, referred to as content based
access. Applications should cover, among other things, digital storage media, content based image and video
databases, internet video, interpersonal video communications, wireless video etc. In the course of creating
ISO/IEC 14496, various requirements from typical applications have been considered, necessary algorithmic
elements have been developed, and they have been integrated into a single syntax. Hence ISO/IEC 14496 will
facilitate the bitstream interchange among different applications.
This part of ISO/IEC 14496 includes one or more complete decoding algorithms as well as a set of decoding tools.
Moreover, the various tools of this part of ISO/IEC 14496 as well as that derived from ISO/IEC 13818-2:1996 can
be combined to form other decoding algorithms. Considering the practicality of implementing the full syntax of this
part of ISO/IEC 14496, however, a limited number of subsets of the syntax are also stipulated by means of “profile”
and “level”.
A “profile” is a defined subset of the entire bitstream syntax that is defined by this part of ISO/IEC 14496. Within the
bounds imposed by the syntax of a given profile it is still possible to require a very large variation in the
performance of encoders and decoders depending upon the values taken by parameters in the bitstream.
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