A Multiplication-Free Algorithm and A Parallel Architecture for Affine Transformation
Affine transformation is widely used in image processing. Recently, it is recommended by MPEG-4 for video motion compensation. This paper presents a novel low power parallel architecture for texture warping using affine transformation (AT). The architecture uses a novel multiplication-free algorithm that employs the algebraic properties of the AT. Low power has been achieved at different levels of the design. At the algorithmic level, replacing multiplication operations with bit shifting saves the power and delay of using a multiplier. At the architecture level, low power is achieved by using parallel computational units, where the latency constraints and/or the operating latency can be reduced. At the circuit level, using low power building blocks (such as low power adders) contributes to the power savings. The proposed architecture is used as a computational kernel in video object coders. It is compatible with MPEG-4 and VRML standards. The architecture has been prototyped in 0.6 μm CMOS technology with three layers of metal. The performance of the proposed architecture shows that it can be used in mobile and handheld applications.
Wael Badawy and Magdy Bayoumi, “A Multiplication-Free Algorithm and A Parallel Architecture for Affine Transformation,” The Journal of VLSI Signal Processing-Systems, Kluwer Academic Publishers, Vol. 31, No 2, May 2002, pp. 173-184.
Low power very large scale integration prototype for three-dimensional discrete wavelet transform processor with medical application
We present a low-power 3-D discrete wavelet transform processor for medical applications. The main focus is the compression of medical resonance image (MRI) data, although the system could be used as a generic compression chip. The architecture eliminates redundant filter banks by using a central control unit to dynamically adjust filter parameters. An on-chip cache is used to process block inputs minimizing result throughput. Power consumption has been kept to a minimum by placing constraints throughout the entire design process. The modular processor has been prototyped using 0.6-μm complementary metal oxide semiconductor (CMOS) (three metal) technology. It has been simulated at the functional, circuit, and physical levels. The performance measures of the prototype, area, time delay, power, and utilization have been evaluated. The prototype operates at an estimated frequency of 272 MHz and dissipates 0.5 W of power.
Wael Badawy, Michael Talley, Guoqing Zhang, Michael Weeks, and Magdy Bayoumi, “Low Power Very Large Scale Integration Prototype for Three-Dimensional Discrete Wavelet Transform Processor with Medical Applications,” The SPIE Journal on Electronic Imaging, Vol. 12, Issue 2, April 2003, pp. 270 – 277.