The Experts below are selected from a list of 53271 Experts worldwide ranked by ideXlab platform
Lianggee Chen - One of the best experts on this subject based on the ideXlab platform.
-
flipping structure an efficient vlsi architecture for lifting based Discrete Wavelet Transform
IEEE Transactions on Signal Processing, 2004Co-Authors: Chaotsung Huang, Pochih Tseng, Lianggee ChenAbstract:In this paper, an efficient very large scale integration (VLSI) architecture, called flipping structure, is proposed for the lifting-based Discrete Wavelet Transform. It can provide a variety of hardware implementations to improve and possibly minimize the critical path as well as the memory requirement of the lifting-based Discrete Wavelet Transform by flipping conventional lifting structures. The precision issues are also analyzed. By case studies of the JPEG2000 default lossy (9,7) filter, an integer (9,7) filter, and the (6,10) filter, the efficiency of the proposed flipping structure is demonstrated.
-
efficient vlsi architectures of lifting based Discrete Wavelet Transform by systematic design method
International Symposium on Circuits and Systems, 2002Co-Authors: Chaotsung Huang, Pochih Tseng, Lianggee ChenAbstract:In this paper, an effective systematic design method is proposed to construct several efficient VLSI architectures of 1-D and 2-D lifting-based Discrete Wavelet Transform. This design method first performs a specific lifting factorization for any finite Discrete Wavelet Transform filter to obtain an optimal algorithm representation for hardware implementation. The optimized algorithm then turns into 1-D systolic architectures through dependence graph formation and systolic arrays mapping. Based on the 1-D architectures, a general 2-D Discrete Wavelet Transform framework is used to construct the corresponding 2-D architectures. According to the comparison results, the constructed VLSI architectures are more efficient than previous arts in term of arithmetic units and memory storage.
-
lifting based Discrete Wavelet Transform architecture for jpeg2000
International Symposium on Circuits and Systems, 2001Co-Authors: Chungjr Lian, Kuanfu Chen, Honghui Chen, Lianggee ChenAbstract:A lifting based 1-D Discrete Wavelet Transform (DWT) core is proposed. It is re-configurable for 5/3 and 9/7 filters in JPEG2000. Folded architecture is adopted to reduce the hardware cost and achieve the higher hardware utilization. Multiplication is realized in hardwired multiplier with coefficients represented in canonic signed-digit (CSD) form. It is a compact and efficient DWT core for the hardware implementation of JPEG2000 encoder.
M J Shensa - One of the best experts on this subject based on the ideXlab platform.
-
the Discrete Wavelet Transform wedding the a trous and mallat algorithms
IEEE Transactions on Signal Processing, 1992Co-Authors: M J ShensaAbstract:Two separately motivated implementations of the Wavelet Transform are brought together. It is observed that these algorithms are both special cases of a single filter bank structure, the Discrete Wavelet Transform, the behavior of which is governed by the choice of filters. In fact, the a trous algorithm is more properly viewed as a nonorthonormal multiresolution algorithm for which the Discrete Wavelet Transform is exact. Moreover, it is shown that the commonly used Lagrange a trous filters are in one-to-one correspondence with the convolutional squares of the Daubechies filters for orthonormal Wavelets of compact support. A systematic framework for the Discrete Wavelet Transform is provided, and conditions are derived under which it computes the continuous Wavelet Transform exactly. Suitable filter constraints for finite energy and boundedness of the Discrete Transform are also derived. Relevant signal processing parameters are examined, and it is observed that orthonormality is balanced by restrictions on resolution. >
-
The Discrete Wavelet Transform
1991Co-Authors: M J ShensaAbstract:Abstract : In a general sense, this report represents an effort to clarify the relationship of Discrete and continuous Wavelet Transforms. More narrowly, it focuses on bringing together two separately motivated implementations of the Wavelet Transform, the algorithm a trous and Mallat's multiresolution decomposition. These algorithms are special cases of a single filter bank structure, the Discrete Wavelet Transform, the behavior of which is governed by one's choice of filters. In fact, the a trous algorithm, originally devised as a computationally efficient implementation, is more properly viewed as a nonorthogonal multiresolution algorithm for which the Discrete Wavelet Transform is exact. Moreover, we show that the commonly used Lagrange a trous filters are in one-to-one correspondence with the convolutional squares of the Daubechies filters for orthonormal Wavelets of compact support. A systematic framework for the Discrete Wavelet Transform is provided, and conditions are derived under which it computer the continuous Wavelet Transform exactly. Suitable filter constraints for finite energy and boundedness of the Discrete Transform are also derived. Finally, relevant signal-processing parameters are examined, and it is remarked that orthonormality is balanced by restrictions on resolution.
Chaotsung Huang - One of the best experts on this subject based on the ideXlab platform.
-
flipping structure an efficient vlsi architecture for lifting based Discrete Wavelet Transform
IEEE Transactions on Signal Processing, 2004Co-Authors: Chaotsung Huang, Pochih Tseng, Lianggee ChenAbstract:In this paper, an efficient very large scale integration (VLSI) architecture, called flipping structure, is proposed for the lifting-based Discrete Wavelet Transform. It can provide a variety of hardware implementations to improve and possibly minimize the critical path as well as the memory requirement of the lifting-based Discrete Wavelet Transform by flipping conventional lifting structures. The precision issues are also analyzed. By case studies of the JPEG2000 default lossy (9,7) filter, an integer (9,7) filter, and the (6,10) filter, the efficiency of the proposed flipping structure is demonstrated.
-
efficient vlsi architectures of lifting based Discrete Wavelet Transform by systematic design method
International Symposium on Circuits and Systems, 2002Co-Authors: Chaotsung Huang, Pochih Tseng, Lianggee ChenAbstract:In this paper, an effective systematic design method is proposed to construct several efficient VLSI architectures of 1-D and 2-D lifting-based Discrete Wavelet Transform. This design method first performs a specific lifting factorization for any finite Discrete Wavelet Transform filter to obtain an optimal algorithm representation for hardware implementation. The optimized algorithm then turns into 1-D systolic architectures through dependence graph formation and systolic arrays mapping. Based on the 1-D architectures, a general 2-D Discrete Wavelet Transform framework is used to construct the corresponding 2-D architectures. According to the comparison results, the constructed VLSI architectures are more efficient than previous arts in term of arithmetic units and memory storage.
Nizamettin Aydin - One of the best experts on this subject based on the ideXlab platform.
-
Denoising embolic doppler signals using modified complex Discrete Wavelet Transform
2011 IEEE 19th Signal Processing and Communications Applications Conference (SIU), 2011Co-Authors: Gorkem Serbes, Nizamettin AydinAbstract:Stroke is the rapidly developing loss of brain functions, due to a disturbance in the blood vessels supplying blood to the brain. The particles in circulation system, bigger than red blood cells, are accepted as the main reason of emboli. Early and accurate detection of asymptomatic emboli is important in monitoring stroke-prone patients. The main problem in detection of emboli is the identification of embolic signals caused by very small emboli. The amplitude of embolic signals can be very small and advanced signal processing techniques are needed to distinguish these signals from Doppler signals arising from red blood cells. In this study instead of conventional Discrete Wavelet Transform, which is used frequently in processing embolic signals, a modified complex Discrete Wavelet Transform with same computational complexity and better phase shift-invariance property was used for de-noising embolic signals. Results demonstrates that approximately 8 dB improvement is obtained by using modified complex Discrete Wavelet Transform compared to the improvement provided by the conventional Discrete Wavelet Transform, approximately 5 dB.
-
Denoising embolic Doppler ultrasound signals using Dual Tree Complex Discrete Wavelet Transform
2010 Annual International Conference of the IEEE Engineering in Medicine and Biology, 2010Co-Authors: Gorkem Serbes, Nizamettin AydinAbstract:Early and accurate detection of asymptomatic emboli is important for monitoring of preventive therapy in stroke-prone patients. One of the problems in detection of emboli is the identification of an embolic signal caused by very small emboli. The amplitude of the embolic signal may be so small that advanced processing methods are required to distinguish these signals from Doppler signals arising from red blood cells. In this study instead of conventional Discrete Wavelet Transform, the Dual Tree Complex Discrete Wavelet Transform was used for denoising embolic signals. Performances of both approaches were compared. Unlike the conventional Discrete Wavelet Transform Discrete complex Wavelet Transform is a shift invariant Transform with limited redundancy. Results demonstrate that the Dual Tree Complex Discrete Wavelet Transform based denoising outperforms conventional Discrete Wavelet denoising. Approximately 8 dB improvement is obtained by using the Dual Tree Complex Discrete Wavelet Transform compared to the improvement provided by the conventional Discrete Wavelet Transform (less than 5 dB).
-
A complex Discrete Wavelet Transform for processing quadrature Doppler ultrasound signals
2009 9th International Conference on Information Technology and Applications in Biomedicine, 2009Co-Authors: Gorkem Serbes, Nizamettin AydinAbstract:Unlike the conventional Discrete Wavelet Transform Discrete complex Wavelet Transform is a shift invariant Transform with limited redundancy. Quadrature Doppler ultrasound signals are dual channel signals obtained from the systems employing quadrature demodulation. Prior to processing Doppler signals by using Discrete Wavelet Transform, directional flow signals must be obtained and then two separate Transform applied, increasing the computational complexity. In order to decrease computational complexity, a complex Discrete Wavelet Transform algorithm is proposed. A comparison between the new Transform and the conventional technique is presented. The results show that the proposed method gives the same output as the conventional technique and the computational complexity for processing quadrature signals using Discrete complex Wavelet Transform is greatly reduced.
Pochih Tseng - One of the best experts on this subject based on the ideXlab platform.
-
flipping structure an efficient vlsi architecture for lifting based Discrete Wavelet Transform
IEEE Transactions on Signal Processing, 2004Co-Authors: Chaotsung Huang, Pochih Tseng, Lianggee ChenAbstract:In this paper, an efficient very large scale integration (VLSI) architecture, called flipping structure, is proposed for the lifting-based Discrete Wavelet Transform. It can provide a variety of hardware implementations to improve and possibly minimize the critical path as well as the memory requirement of the lifting-based Discrete Wavelet Transform by flipping conventional lifting structures. The precision issues are also analyzed. By case studies of the JPEG2000 default lossy (9,7) filter, an integer (9,7) filter, and the (6,10) filter, the efficiency of the proposed flipping structure is demonstrated.
-
efficient vlsi architectures of lifting based Discrete Wavelet Transform by systematic design method
International Symposium on Circuits and Systems, 2002Co-Authors: Chaotsung Huang, Pochih Tseng, Lianggee ChenAbstract:In this paper, an effective systematic design method is proposed to construct several efficient VLSI architectures of 1-D and 2-D lifting-based Discrete Wavelet Transform. This design method first performs a specific lifting factorization for any finite Discrete Wavelet Transform filter to obtain an optimal algorithm representation for hardware implementation. The optimized algorithm then turns into 1-D systolic architectures through dependence graph formation and systolic arrays mapping. Based on the 1-D architectures, a general 2-D Discrete Wavelet Transform framework is used to construct the corresponding 2-D architectures. According to the comparison results, the constructed VLSI architectures are more efficient than previous arts in term of arithmetic units and memory storage.