Incorporation of biorthogonality into lapped transforms for audio compression
نویسندگان
چکیده
Acoustic signal representations used in current audio coding algorithms can be improved by the incorporation of biorthogonality into Malvar's Extended Lapped Transform (ELT). Biorthogonality allows more exibility in the design of the analysis and synthesis windows by increasing the number of degrees of freedom. This paper examines this increase for two special cases and demonstrates the importance of the additional exibility to the proper implementation of psychoacoustic modeling, a feature central to all modern audio compression schemes.
منابع مشابه
Biorthogonality in lapped transforms: a study in high-quality audio compression
The demand for high-quality audio in transmission systems such as Digital Audio Broadcast (DAB) and High-Definition TeleVision (HDTV), as well as commercial products such as the MiniDisc (MD) and the Digital Compact Cassette (DCC), has generated considerable interest in audio compression schemes. The common objective is to achieve high quality at a rate significantly smaller than the 16 bits/sa...
متن کامل2 . 4 Biorthogonality in Lapped Transforms : A Study in Audio Compression
The present television system was designed nearly 50 years ago. Since then, there have been significant developments in technology, which are highly relevant to the television industry. For example, advances in the very large scale integration (VLSI) technology and signal processing theories make it feasible to incorporate frame-store memory and sophisticated signal processing capabilities in a...
متن کاملLapped Transforms in a JPEG 2000 Coder
JPEG-2000 is the latest image coding standard and is based on wavelet transforms and dyadic spectral decompositions. We have adapted the JPEG-2000 image coder for use with uniform transforms, by replacing the wavelet stage by lapped transforms. We set code-blocks that do not cross subband boundaries and encode the lapped transform coefficients directly as if they were wavelet ones. Results indi...
متن کاملLapped Transforms for Image Compression
This chapter covers the basic aspects of lapped transforms and their applications to image compression. It is a subject that has been extensively studied mainly because lapped transforms are closely related to lter banks, wavelets, and time-frequency transformations. Some of these topics are also covered in other chapters in this book. In any case it is certainly impractical to reference all th...
متن کاملFast Computing of Discrete Cosine and Sine Transforms of Types VI and VII
The Discrete Sine and Cosine Transforms (DST and DCT) have already received considerable attention due to their use in source coding. The DCT of type-II (DCT-II) is at the core of standards for image and video compression, such as JPEG, H.26x-series, and MPEG 1-4 standards. The DST of type-I was suggested as a basis for Recursive Block Coding technique. The DCT and DST of type IV are used in de...
متن کامل