tailieunhanh - Báo cáo hóa học: " Research Article A Generalized Approach to Linear Transform Approximations with Applications to the Discrete Cosine Transform"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article A Generalized Approach to Linear Transform Approximations with Applications to the Discrete Cosine Transform | Hindawi Publishing Corporation EURASIP Journal on Advances in Signal Processing Volume 2008 Article ID 736460 17 pages doi 2008 736460 Research Article A Generalized Approach to Linear Transform Approximations with Applications to the Discrete Cosine Transform Yinpeng Chen and Hari Sundaram The Katherine K. Herberger College of the Arts and the Ira A. Fulton School of Engineering Arts Media and Engineering Program Arizona State University Tempe AZ 85281 USA Correspondence should be addressed to Hari Sundaram Received 13 June 2007 Revised 1 February 2008 Accepted 17 March 2008 Recommended by Lisimachos P. Kondi This paper aims to develop a generalized framework to systematically trade off computational complexity with output distortion in linear transforms such as the DCT in an optimal manner. The problem is important in real-time systems where the computational resources available are time-dependent. Our approach is generic and applies to any linear transform and we use the DCT as a specific example. There are three key ideas a a joint transform pruning and Haar basis projection-based approximation technique. The idea is to save computations by factoring the DCT transform into signal-independent and signal-dependent parts. The signal-dependent calculation is done in real-time and combined with the stored signal-independent part saving calculations. b We propose the idea of the complexity-distortion framework and present an algorithm to efficiently estimate the complexity distortion function and search for optimal transform approximation using several approximation candidate sets. We also propose a measure to select the optimal approximation candidate set and c an adaptive approximation framework in which the operating points on the C-D curve are embedded in the metadata. We also present a framework to perform adaptive approximation in real time for changing computational resources by using the embedded metadata. Our results validate .