This paper presents the design and implementation of a compression system for grayscale images based on the Bandelet transform. The basis functions of the Bandelet transform are constructed as a set of vectors that indicate the directions in which the image has regular variations of gray. The compression system was designed as a SoPC and was composed of a NIOSII processor with a Cyclone IIEP2C70, a touch-panel, and a SD-Card, using 13% of the logic elements and 27% of the memory bits of the FPGA. The Wavelet filters were accelerated in hardware with NIOS II C2H Compiler, obtaining an execution time reduction of 8.8%. Experimental results show that Bandelet compression has an improvement of up to 2 dB over a Wavelet compression when the image has geometric components with high contrast.
Universidad de Tarapacá.
Ingeniare. Revista chilena de ingeniería v.20 n.2 2012
Design of image codec based on Bandelet transform using a NIOS II processor