Hindawi Publishing Corporation
Journal of Electrical and Computer Engineering
Volume 2013, Article ID 834793, 9 pages
http://dx.doi.org/10.1155/2013/834793
Research Article
Asynchronous Realization of Algebraic Integer-Based 2D DCT
Using Achronix Speedster SPD60 FPGA
Nilanka Rajapaksha,
1
Amila Edirisuriya,
1
Arjuna Madanayake,
1
Renato J. Cintra,
2
Dennis Onen,
3
Ihab Amer,
4
and Vassil S. Dimitrov
3
1
Electrical and Computer Engineering, Auburn Science and Engineering Center (ASEC) 265,
he University of Akron, Akron, OH 44325-3904, USA
2
Signal Processing Group, Department of Statistics, Federal University of Pernambuco, 50740-540 Recife, PE, Brazil
3
Department of Electrical and Computer Engineering, ICT 402, Schulich School of Engineering, University of Calgary, 2500 University
Drive NW Calgary, Alberta, Calgary, AB, Canada T2N 1N4
4
Advanced Micro Devices, 1 Commerce Valley Drive East, Markham, ON, Canada L3T 7X6
Correspondence should be addressed to Arjuna Madanayake; arjuna@uakron.edu
Received 28 November 2012; Revised 23 February 2013; Accepted 25 February 2013
Academic Editor: Antonio G. M. Strollo
Copyright © 2013 Nilanka Rajapaksha et al. his is an open access article distributed under the Creative Commons Attribution
License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly
cited.
Transformation and quantization play a critical role in video codecs. Recently proposed algebraic-integer-(AI-) based discrete
cosine transform (DCT) algorithms are analyzed in the presence of quantization, using the High Eiciency Video Coding
(HEVC) standard. AI DCT is implemented and tested on asynchronous quasi delay-insensitive logic, using Achronix SPD60 ield
programmable gate array (FPGA), which leads to lower complexity, higher speed of operation, and insensitivity to process-voltage-
temperature variations. Performance of AI DCT with HEVC is measured in terms of the accuracy of the transform coeicients
and the overall rate-distortion (R-D) characteristics, using HM 7.1 reference sotware. Results indicate a 31% improvement over the
integer DCT in the number of transform coeicients having error within 1%. he performance of the 65 nm asynchronous hardware
in terms of speed of operation is investigated and compared with the 65 nm synchronous Xilinx FPGA. Considering word lengths
of 5 and 6 bits, a speed increase of 230% and 199% is observed, respectively. hese results indicate that AI DCT can be potentially
utilized in HEVC for applications demanding high accuracy as well as high throughput. However, novel quantization schemes are
required to allow the accuracy improvements obtained.
1. Introduction
High dynamic range (HDR) video and image transmis-
sion over digital communication channels is undergoing
exponential growth [1]. With the increasing demand for
high-deinition programming, there exists a strong need for
eicient digital video coding (DVC) that provides high data
compression ratios which in turn leads to better utilization
of network resources [2]. he H.264/AVC standard [3] does
not provide the required compression ratios for emerging
capture and display technologies such as ultra high deinition
(UHD) [4], multiview [5], and autostereoscopy [6]. To
address such emerging needs, the Joint Collaborative Team
on Video Coding (JCT-VC) has developed the successor for
H.264/AVC, called High Eiciency Video Coding (HEVC)
[4]. he HEVC standard aims at achieving a 50% reduction
in data rate compared with its predecessors while main-
taining low complexity computation. Video compression
systems operating at high frequencies and resolutions require
hardware capable of signiicant throughput with tolerable
area and power requirements. Real-time video compression
circuits having high numerical accuracy are needed for next-
generation video [1], coding systems [2, 3, 7], and retina
displays [8].
he two-dimensional (2D) 8 × 8 discrete cosine transform
(DCT) is a fundamental operation in real-time video systems,
which is adopted in compression standards, such as JPEG,
MPEG-1, MPEG-2, H.261, H.263, H.264, and most recently