scholarly journals A new VLSI algorithm and architecture for the hardware implementation of type IV discrete cosine transform using a pseudo-band correlation structure

2011 ◽  
Vol 1 (2) ◽  
Author(s):  
Doru Chiper

AbstractA new VLSI algorithm and its associated systolic array architecture for a prime length type IV discrete cosine transform is presented. They represent the basis of an efficient design approach for deriving a linear systolic array architecture for type IV DCT. The proposed algorithm uses a regular computational structure called pseudoband correlation structure that is appropriate for a VLSI implementation. The proposed algorithm is then mapped onto a linear systolic array with a small number of I/O channels and low I/O bandwidth. The proposed architecture can be unified with that obtained for type IV DST due to a similar kernel. A highly efficient VLSI chip can be thus obtained with good performance in the architectural topology, computing parallelism, processing speed, hardware complexity and I/O costs similar to those obtained for circular correlation and cyclic convolution computational structures.

Electronics ◽  
2021 ◽  
Vol 10 (14) ◽  
pp. 1656
Author(s):  
Doru Florin Chiper ◽  
Laura-Teodora Cotorobai

This paper aims at solving one challenging problem in designing VLSI chips, namely, the security of the hardware, by presenting a new design approach that incorporates the obfuscation technique in the VLSI implementation of some important DSP algorithms. The proposed method introduces a new approach in obtaining a unified VLSI architecture for computing type IV discrete cosine transform (DCT-IV) and type IV discrete sine transform (DST-IV), with an efficient integration of the obfuscation technique, while maintaining low overheads. The algorithms for these two transforms were restructured in such a way that their structures are fairly similar, and thus they can be implemented on the same VLSI chip and on the same hardware with very few modifications, with the latter being attributed to the pre-processing and post-processing stages. The design proposed uses the regular and modular structures, which are named quasi-correlation, and the architecture is inspired by the paradigm of the systolic array architecture. Thus, the introduced design benefits the security, for the hardware, and also the advantages introduced by the use of the regular and modular structures. A very efficient, unified VLSI architecture for type IV DCT/DST can be obtained, which allows the computation of the two algorithms on the same hardware, allowing an efficient incorporation of the obfuscation technique with very low overheads, and it can be very efficiently implemented, offering high-speed performances and low hardware complexity, with the latter being attributed to the efficient use of the hardware resources for the computation of these two algorithms.


Author(s):  
DANESHWARI I. HATTI ◽  
SAVITRI RAJU ◽  
MAHENDRA M. DIXIT

In digital communication bandwidth is essential parameter to be considered. Transmission and storage of images requires lot of memory in order to use bandwidth efficiently neural network and Discrete cosine transform together are used in this paper to compress images. Artificial neural network gives fixed compression ratio for any images results in fixed usage of memory and bandwidth. In this paper multi-layer feedforward neural network has been employed to achieve image compression. The proposed technique divides the original image in to several blocks and applies Discrete Cosine Transform (DCT) to these blocks as a pre-process technique. Quality of image is noticed with change in training algorithms, convergence time to attain desired mean square error. Compression ratio and PSNR in dB is calculated by varying hidden neurons. The proposed work is designed using MATLAB 7.10. and synthesized by mapping on Vertex 5 in Xilinx ISE for understanding hardware complexity. Keywords - backpropagation, Discrete


Sign in / Sign up

Export Citation Format

Share Document