EURASIP Journal on Applied Signal Processing 
Volume 2002 (2002), Issue 9, Pages 879-892
doi:10.1155/S1110865702205090

Lightweight Floating-Point Arithmetic: Case Study of Inverse Discrete Cosine Transform

Fang Fang, Tsuhan Chen, and Rob A. Rutenbar

Department of Electrical and Computer Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh 15213, PA, USA

Received 15 May 2001; Revised 9 May 2002

Abstract

To enable floating-point (FP) signal processing applications in low-power mobile devices, we propose lightweight floating-point arithmetic. It offers a wider range of precision/power/speed/area trade-offs, but is wrapped in forms that hide the complexity of the underlying implementations from both multimedia software designers and hardware designers. Libraries implemented in C++ and Verilog provide flexible and robust floating-point units with variable bit-width formats, multiple rounding modes and other features. This solution bridges the design gap between software and hardware, and accelerates the design cycle from algorithm to chip by avoiding the translation to fixed-point arithmetic. We demonstrate the effectiveness of the proposed scheme using the inverse discrete cosine transform (IDCT), in the context of video coding, as an example. Further, we implement lightweight floating-point IDCT into hardware and demonstrate the power and area reduction.