Fixed-point optimization utility for C and C++ based digital signal processing programs

• Published in: IEEE transactions on circuits and systems. 2, Analog and digital signal processing Vol. 45; no. 11; pp. 1455 - 1464
• Main Authors: Kim, Seehyun, Kum, Ki-Il, Sung, Wonyong
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.11.1998; Institute of Electrical and Electronics Engineers
• Subjects: Algorithm design and analysis; Applied sciences; Circuit properties; Circuit simulation; Computer architecture; Digital circuits; Digital signal processing; Electric, optical and optoelectronic circuits; Electrical and electronic components, instruments and techniques; Electronic circuits; Electronics; Exact sciences and technology; Finite wordlength effects; Fixed-point arithmetic; Floating-point arithmetic; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Physics; Signal processing algorithms; Signal processing electronics; Software algorithms; Utility programs; VLSI circuit; Program; Simulation; Signal processing; Word length; Finite word; Experimental study; Optimization; Digital signal; Fixed point
• ISSN: 1057-7130; 1558-125X
• DOI: 10.1109/82.735357

Fixed-point optimization utility software is developed that can aid scaling and wordlength determination of digital signal processing algorithms written in C or C++. This utility consists of two programs: the range estimator and the fixed-point simulator. The former estimates the ranges of floating-point variables for purposes of automatic scaling, and the latter translates floating-point programs into fixed-point equivalents to evaluate the fixed-point performance by simulation. By exploiting the operator overloading characteristics of C++, the range estimation and the fixed-point simulation can be conducted by simply modifying the variable declaration of the original program. This utility is easily applicable to nearly all types of digital signal processing programs including nonlinear, time-varying, multirate, and multidimensional signal processing algorithms. In addition, this software can be used to compare the fixed-point characteristics of different implementation architectures. An optimization example for an 8/spl times/8 inverse discrete cosine transform (IDCT) architecture that conforms to the IEEE standard specifications is presented. The optimized results require 8% fewer gates when compared with the previous best implementation.