VLSI design of 1-D DWT architecture with parallel filters

Wavelet transform coding has been drawing much attention because of its ability to decompose images into a hierarchical structure that is suitable for adaptive processing in the transform domain. This paper presents an Efficient VLSI design of one-dimensional direct discrete wavelet transform processor. The proposed architecture computes three DWT stages and uses four parallel filters. The architecture is simple and offers 16-bit precision on input and output data. It is constituted of three basic units: one storage unit, four filters, and a control unit. No memory or registers are used for storing intermediate results. Furthermore, data scheduling and memory management remain very simple. The end result is an efficient VLSI implementation with a reduced area cost compared to the conventional approaches. The architecture can compute DWT at a data rate of 7×106 samples/s corresponding to a typical clock speed of 7 MHz. The architecture is simulated and verified at the gate level in VLSI. Process parameters used were those of 0.6 μm technology. The chip area is about 15.7 mm2.