825 research outputs found

    New memory-efficient hardware architecture of 2-D dual-mode lifting-based discrete wavelet transform for JPEG2000

    Get PDF
    [[abstract]]This work presents new algorithms and hardware architectures to improve the critical issues of the 2-D dual-mode (supporting 5/3 lossless and 9/7 lossy coding) lifting-based discrete wavelet transform (LDWT). The proposed 2-D dual-mode LDWT architecture has the advantages of low-transpose memory, low latency, and regular signal flow, which is suitable for VLSI implementation. The transpose memory requirement of the N ?? N 2-D 5/3 mode LDWT is 2N, and that of 2-D 9/7 mode LDWT is 4N. According to the comparison results, the proposed hardware architecture surpasses previous architectures in the aspects of lifting-based low-transpose memory size. It can be applied to real-time visual operations such as JPEG2000, MPEG-4 still texture object decoding, and wavelet-based scalable video coding.[[notice]]需補會議日期、性質、主辦單位[[conferencedate]]20081119~2008112

    Memory-efficient architecture of 2-D dual-mode discrete wavelet transform using lifting scheme for motion-JPEG2000

    Get PDF
    [[abstract]]In this work, we propose a memory-efficient architecture of lifting based two-dimensional discrete wavelet transform (2D DWT) for motion-JPEG2000. The proposed 2D DWT architecture consists of a 1D row processor, internal memory, and a 1D column processor. The main advantage of this 2D DWT is to reduce the internal memory requirement significantly. For an NtimesN image, only 2N and 4N sizes of internal memory are required for the 5/3 and 9/7 filters, respectively, to perform the one-level 2D DWT decomposition. Moreover, it supports both lossless and lossy operation for 5/3 and 9/7 filters with high operation speed. The proposed 2D DWT surpasses the existed lifting-based designs in the aspects of low internal memory requirement. It is suitable for VLSI implementation and can support various real-time image/video applications such as JPEG2000, motion-JPEG2000, MPEG-4 still texture object decoding, and wavelet-based scalable video coding.[[notice]]需補會議日期、性質、主辦單位[[conferencedate]]20090524~2009052

    Efficient Hardware Implementation Of Haar Wavelet Transform With Line-Based And Dual-Scan Image Memory Accesses

    Get PDF
    Image compression is of great importance in multimedia systems and applications because it drastically reduces bandwidth requirements for transmission and memory requirements for storage. An image compression algorithm JPEG2000 isbased on Discrete Wavelet Transform. In the hardware implementation of DiscreteWavelet Transform (DWT) and inverse DiscreteWavelet Transform (IDWT),the main problems are storage memory, internal processing buffer, and the limitation of the FPGA resources. Based on non-separable 2-D DWT, the method used to access the image memory has a direct impact on the internal buffer size,the power consumption and, the transformation speed. The need for internal buffer reduces the image memory access time. The main objectives of this thesis are as follows; to implement a 2-D Haar wavelet transform for large gray-scale image, to reduce the number of image memory access by implementing the 2- D Haar wavelet transform with a suitable combination between using external memory and internal memory, and targeting a low-power and high-speed architecture based on multi-levels non-separable discrete Haar wavelet transform. In this work, the proposed two architectures reduce the number of image memory access. The line-based architecture reduces the internal buffer by 2 x 0.5 x N where N presents the image size. This happens for the low-pass coefficients and for the high-pass coefficients. The dual-scan architecture does not use the internal memory. Overall both architectures work well on the Altera FPGA board at frequency 100 MHz

    Single event upset hardened embedded domain specific reconfigurable architecture

    Get PDF

    Complexity Reduction and Fast Algorithm for 2-D Integer Discrete Wavelet Transform Using Symmetric Mask-Based Scheme

    Get PDF
    [[abstract]]Wavelet coding has been shown to be better than discrete cosine transform (DCT) in image/video processing. Moreover, it has the feature of scalability, which is involved in modern video standards. This work presents novel algorithms, namely 2-D symmetric mask-based discrete wavelet transform (SMDWT), to improve the critical issue of the 2-D lifting-based discrete wavelet transform (LDWT), and then obtains the benefit of low latency, high-speed operation, and low temporal memory. The SMDWT also has the advantages of high-performance embedded periodic extension boundary treatment, reduced complexity, regular signal coding, short critical path, reduced latency time, and independent subband coding processing. Moreover, the 2-D lifting-based DWT performance can also be easily improved by exploiting appropriate parallel method inherently in SMDWT. Comparing with the normal 2-D 5/3 integer lifting-based DWT the proposed method significantly improves lifting-based latency and complexity in 2-D DWT without degradation in image quality. The algorithm can be applied to real-time image/video applications, such as JPEG2000, MPEG-4 still texture object decoding, and wavelet-based Scalable Video Coding (SVC).[[sponsorship]]IEEE Computer Society, U.S.A.[[notice]]需補會議地點[[conferencetype]]國際[[conferencedate]]20071210~2007121

    Efficient reconfigurable architectures for 3D medical image compression

    Get PDF
    This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Recently, the more widespread use of three-dimensional (3-D) imaging modalities, such as magnetic resonance imaging (MRI), computed tomography (CT), positron emission tomography (PET), and ultrasound (US) have generated a massive amount of volumetric data. These have provided an impetus to the development of other applications, in particular telemedicine and teleradiology. In these fields, medical image compression is important since both efficient storage and transmission of data through high-bandwidth digital communication lines are of crucial importance. Despite their advantages, most 3-D medical imaging algorithms are computationally intensive with matrix transformation as the most fundamental operation involved in the transform-based methods. Therefore, there is a real need for high-performance systems, whilst keeping architectures exible to allow for quick upgradeability with real-time applications. Moreover, in order to obtain efficient solutions for large medical volumes data, an efficient implementation of these operations is of significant importance. Reconfigurable hardware, in the form of field programmable gate arrays (FPGAs) has been proposed as viable system building block in the construction of high-performance systems at an economical price. Consequently, FPGAs seem an ideal candidate to harness and exploit their inherent advantages such as massive parallelism capabilities, multimillion gate counts, and special low-power packages. The key achievements of the work presented in this thesis are summarised as follows. Two architectures for 3-D Haar wavelet transform (HWT) have been proposed based on transpose-based computation and partial reconfiguration suitable for 3-D medical imaging applications. These applications require continuous hardware servicing, and as a result dynamic partial reconfiguration (DPR) has been introduced. Comparative study for both non-partial and partial reconfiguration implementation has shown that DPR offers many advantages and leads to a compelling solution for implementing computationally intensive applications such as 3-D medical image compression. Using DPR, several large systems are mapped to small hardware resources, and the area, power consumption as well as maximum frequency are optimised and improved. Moreover, an FPGA-based architecture of the finite Radon transform (FRAT)with three design strategies has been proposed: direct implementation of pseudo-code with a sequential or pipelined description, and block random access memory (BRAM)- based method. An analysis with various medical imaging modalities has been carried out. Results obtained for image de-noising implementation using FRAT exhibits promising results in reducing Gaussian white noise in medical images. In terms of hardware implementation, promising trade-offs on maximum frequency, throughput and area are also achieved. Furthermore, a novel hardware implementation of 3-D medical image compression system with context-based adaptive variable length coding (CAVLC) has been proposed. An evaluation of the 3-D integer transform (IT) and the discrete wavelet transform (DWT) with lifting scheme (LS) for transform blocks reveal that 3-D IT demonstrates better computational complexity than the 3-D DWT, whilst the 3-D DWT with LS exhibits a lossless compression that is significantly useful for medical image compression. Additionally, an architecture of CAVLC that is capable of compressing high-definition (HD) images in real-time without any buffer between the quantiser and the entropy coder is proposed. Through a judicious parallelisation, promising results have been obtained with limited resources. In summary, this research is tackling the issues of massive 3-D medical volumes data that requires compression as well as hardware implementation to accelerate the slowest operations in the system. Results obtained also reveal a significant achievement in terms of the architecture efficiency and applications performance.Ministry of Higher Education Malaysia (MOHE), Universiti Tun Hussein Onn Malaysia (UTHM) and the British Counci

    Two Dimensional Dual-Mode Lifting Based Discrete Wavelet Transform

    Get PDF
    Hardware Simplicity, Multiplier-less architecture is proposed which is applicable for both lossy and lossless coding
    corecore