Path: utzoo!utgpu!watmath!thunder!water!wlrush
From: wlrush@water.waterloo.edu (Wenchantress Wench Wendall)
Newsgroups: ont.events,uw.talks,uw.cs.grad
Subject: COMPUTER GRAPHICS SEMINAR
Keywords: Mr. Paul Heckert, University of California-Berkeley and
Message-ID: <2465@water.waterloo.edu>
Date: 22 Jun 89 12:51:09 GMT
Distribution: ont
Organization: U of Waterloo, Ontario
Lines: 33

Apple Computer, will speak on ``An In-Place Image Zoom Algorithm.''


DEPARTMENT OF COMPUTER SCIENCE
UNIVERSITY OF WATERLOO
SEMINAR ACTIVITIES

COMPUTER GRAPHICS SEMINAR

                    -Monday, June 26, 1989

Mr. Paul Heckbert, University of California-Berkeley and Apple Computer,
will speak on ``An In-Place Image Zoom Algorithm''

TIME:                 3:30 p.m.

ROOM:              DC 1302

ABSTRACT

Standard   image   processing   algorithms  operate  in
scanline  order.  If one attempts to translate or scale
an   image  with  overlapping  source  and  destination
windows using such an algorithm, information-destroying
feedback results.  Borrowing tricks from block transfer
firmware,  we  can  make  slight  modifications  to the
scanline algorithm to eliminate all feedback.  Happily,
the  technique  generalizes  easily  to allow arbitrary
finite   impulse  response  filtering.   The  resulting
algorithm  for  in-place filtered image zooming appears
to  subsume  previous  one-pass scanline algorithms for
both  in-place FIR filtering and in-place zooming, with
no loss in efficiency.