Applying the MDCT to image compression
Date
2009-03
Authors
Muller, Rikus
Journal Title
Journal ISSN
Volume Title
Publisher
Stellenbosch : University of Stellenbosch
Abstract
The replacement of the standard discrete cosine transform (DCT) of JPEG with the
windowed modifed DCT (MDCT) is investigated to determine whether improvements
in numerical quality can be achieved. To this end, we employ an existing algorithm
for optimal quantisation, for which we also propose improvements. This involves the
modelling and prediction of quantisation tables to initialise the algorithm, a strategy that
is also thoroughly tested. Furthermore, the effects of various window functions on the
coding results are investigated, and we find that improved quality can indeed be achieved
by modifying JPEG in this fashion.
Description
Thesis (DSc (Mathematical Sciences. Applied Mathematics))--University of Stellenbosch, 2009.
Keywords
Windowed modified DCT, JPEG (Image coding standard), Discrete cosine transforms, Image compression, Dissertations -- Applied mathematics, Theses -- Applied mathematics