An Efficient VLSI Architecture for PIECEWISE Lifting Based DWT

The discrete wavelet transform (DWT) plays a central role in a number of signal and image processing applications. The lifting scheme is a new algorithm proposed for the implementation of the wavelet transform. It can reduce the computational complexity of DWT involved with the convolution implementation. The lifting scheme consists of the following three steps Split, Predict and Update step. In conventional Lifting Scheme based DWT, complete image is divided into two parts that is even and odd image pixels. One even and one odd image pixel leads to PREDICT and UPDATE steps. In Piecewise Lifting Scheme DWT, image is not divided into even and odd sections, but the complete image is windowed. Windowing technique is applied throughout the complete image so as to have equal number of pixels in each window. Lifting Scheme provides zoom in and zooms out of image. The main advantage of the proposed architecture is its inherent speed due to elimination of the multipliers in computing DWT/IDWT.