Design of image codec based on Bandelet transform using a NIOS II processor

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.