A real time, low latency, hardware implementation of the 2D discrete wavelet transformation for streaming image applications

Abstract

We present a 2D discrete wavelet transformation (DWT) hardware for applications where row-based raw image data is streamed in at high bandwidths and local buffering of the entire image is not feasible. The latency that is introduced as the images stream through the DWT filter and the amount of locally stored image data is a function of the image and tile size. For an n/sub 1//spl times/n/sub 2/ size image processed using (n/sub 1//k/sub 1/)/spl times/(n/sub 2//k/sub 2/) sized tiles, the latency is equal to the time elapsed to accumulate a (1/k/sub 1/) portion of one image. In addition, a (2/k/sub 1/) potion of each image is buffered locally. The proposed hardware has been implemented on an FPGA and is part of a JPEG2000 compression system designed as a payload for a low Earth orbit (LEO) micro-satellite, which is due to be launched in August 2003.