INTERNATIONAL ORGANISATION FOR STANDARDISATION
ORGANISATION INTERNATIONALE DE NORMALISATION
CODING OF MOVING PICTURES AND AUDIO
October 1999 / Melbourne
Source: Audio Subgroup
Title: Revised Report on Complexity of MPEG-2 AAC Tools
Authors: S. R. Quackenbush, Y. Toguri, and Jürgen Herre
|This web page contains only excerpts of the document. The complete document is available as PDF file.|
This document is based on document and N2005, which presented the complexity of the tools in MPEG-2 AAC Main, Low Complexity and Sampling Scalable Rate Profiles. In addition, an analysis of the complexity of a one-band AAC Scaleable Sampling Rate (SSR) Profile decoder is provided in an annex of this document.
We desire to quantify the complexity of the tools in the MPEG-2 Advanced Audio Coding (AAC) decoder. They are:
Unless otherwise indicated, complexity is specified in terms of
We assume that:
Furthermore, we only indicate storage that is required by a tool and cannot be shared or re-used by other tools. Specifically, we do not count temporary, stack-based scratch storage ("automatic" variables), as such storage is implicitly shared across tools.
Unless explicitly indicated, all complexity figures are for one audio channel.
One should consider two important categories of AAC decoder implementations: software decoders running on general-purpose processors, and hardware decoders running on single-chip ASICs. For these two categories the data presented in this document, augmented by demonstrated real-time software decoder implementations, can be summarized in the following table:
|2-channel Main profile software decoder||40 % of 133 MHz Pentium|
|2-channel Low Complexity profile software decoder||25 % of 133 MHz Pentium|
|5-channel Main profile hardware decoder||90 sq. mm die, 0.5 micron CMOS|
|5-channel Low Complexity profile hardware decoder||60 sq. mm die, 0.5 micron CMOS|
|2-channel Scaleable Sampling Rate profile software decoder||not estimated|
|5-channel Scaleable Sampling Rate profile hardware decoder||53 sq. mm die, 0.5 micron CMOS (3 band decoder)|
In this Table, the 3-band SSR decoder complexity is shown. The 4-band SSR decoder has almost the same complexity as Low Complexity Profile.
Heiko Purnhagen 08-Feb-2000