1,994 research outputs found

    A VLSI architecture of JPEG2000 encoder

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    Copyright @ 2004 IEEEThis paper proposes a VLSI architecture of JPEG2000 encoder, which functionally consists of two parts: discrete wavelet transform (DWT) and embedded block coding with optimized truncation (EBCOT). For DWT, a spatial combinative lifting algorithm (SCLA)-based scheme with both 5/3 reversible and 9/7 irreversible filters is adopted to reduce 50% and 42% multiplication computations, respectively, compared with the conventional lifting-based implementation (LBI). For EBCOT, a dynamic memory control (DMC) strategy of Tier-1 encoding is adopted to reduce 60% scale of the on-chip wavelet coefficient storage and a subband parallel-processing method is employed to speed up the EBCOT context formation (CF) process; an architecture of Tier-2 encoding is presented to reduce the scale of on-chip bitstream buffering from full-tile size down to three-code-block size and considerably eliminate the iterations of the rate-distortion (RD) truncation.This work was supported in part by the China National High Technologies Research Program (863) under Grant 2002AA1Z142

    VLSI architecture of low memory and high speed 2D lifting-based discrete wavelet transform for JPEG2000 applications

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    [[abstract]]The paper presents a low memory and high speed VLSI architecture for 2D lifting-based lossless 5/3 filter discrete wavelet transform (DWT). The architecture is based on the proposed interlaced read scan algorithm (IRSA) and parallel scheme processing to achieve low memory size and high speed operation. The proposed lifting-based DWT architecture has the advantages of lower computational complexity, transforming signal with extension, and regular data flow, and is suitable for VLSI implementation. It can be applied to real time image/video operation of JPEG2000 and MPEG-4 applications. Basing on the proposed architecture, we designed and simulated a 2D DWT VLSI chip by 0.35 弮m 1P4M CMOS technology. The memory requirement of the N?N 2D DWT is N, and it can operate at 100 MHz clock frequency.[[notice]]需補會議日期、性質、主辦單位[[conferencetype]]國際[[conferencedate]]20050523~2005052

    GaAs Implementation of FIR Filter

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    This thesis discusses the findings of the final year project involving Gallium Arsenide implementation of a triangular FIR filter to perform discrete wavelet transforms. The overall characteristics of Gallium Arsenide technology- its construction, behaviour and electrical charactersitics as they apply to VLSI technology - were investigated in this project. In depth understanding of its architecture is required to be able to understand the various design techniques employed. A comparison of Silicon and GaAs performance and other characteristics has also been made to fully justify the choice of this material for system implementation. A lot of research and active interest has gone into the field of image and video compression. Wavelet-based image transformation is one of the very efficient compression techniques used. An analysis of discrete wavelet transformations and the required triangular FIR filter was done to be able to produce a transform algorithm and the related filter architecture. Finally, the filter architecture was implemented as a VLSI design and layout. A variety of functional blocks required for the architecture were designed, tested and analysed. All these blocks were integrated to produce a model of a complete filter cell. The filter implementation was designed to be self-timed - without a system clock. Self-timed systems have considerable advantages over clocked architectures. Various design styles and handshaking mechanisms involved in designing a self-timed system were analysed and designed. There are many avenues still to explore. One of them is the VHDL analysis of filter architecture. Further development on this project would involve integration of higher-level logic and formation of a complete filter array
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