DCT optimisation

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#150

From: Anthony H Phillips
Date: Thu, 28 Jan 1993 22:10

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I am a final year undergraduate doing a software engineering project in Digital Video.
I have implemented a number of image compression algorithms that run on Sun Unix
workstations, among these is a JPEG and MPEG codec. I should immediately add that these
are not true compliant codecs but merely abstract the core ideas present in them. The
problem I have is that I am currently using the standard fast DCT algorithm, but even
with the speed of a Sun/4 processor I cannot get more than a frame a second at 160 by
120 image size. I have already scaled the algorithm into integer maths that helped a
lot but I am stuck for the next move. I have also implemented a fairly sophisticated
motion estimation system which allows me to miss out well matched blocks completely
if the error between the motion estimated blocks and the actual block is below a given
threshold, this obviously presents one way of speeding up the process by simply not
doing an inverse DCT on every block !
Any thoughts and ideas would be greatly appreciated. Anthony Phillips.

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Path: arc1-ca.pugleaf.net!sparky!uunet!pipex!unipalm!uknet!bhamcs!mother!ahp
From: ahp@cs.bham.ac.uk (Anthony H Phillips)
Newsgroups: comp.compression.research
Subject: DCT optimisation
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Date: 28 Jan 93 22:10:22 GMT
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