DSP Implementation of Real-Time JPEG2000 Encoder Using Overlapped Block Transferring and Pipelined Processing

Abstract

This paper presents a DSP implementation of real-time JPEG 2000 encoder system. Among several modules in JPEG 2000 encoder, the lifting algorithm for discrete wavelet transform (DWT) and the embedded block coding with optimized truncation (EBCOT) comprise more than 85% of the encoding complexity. Thus, it is very important to design and optimize these two modules in order to increase the encoding performance. First, we propose a overlapped block transferring (OBT) method that can significantly improve the performance of the lifting algorithm for DWT by increasing the cache hit rate. Next, we introduce a pipelined processing of passes (PPP) method for fast implementation of EBCOT Tier-1. This method reduces the processing time of EBCOT Tier-1 by processing the three coding passes of the same bit-plane like pipeline. Moreover, we propose a computationally efficient method of EBCOT Tier-2 to predict the truncation point by using the temporal redundancy in the image sequence. Experimental results show that our developed Motion-JPEG 2000 DSP system meets the common requirement of the real-time video coding [30 frames/s (fps)] and is proven to be a practical and efficient DSP solution.