Monday, October 22, 2007

Internet users quick to judge

By Judy Skatssoon for Science Online

Internet users can take just one-twentieth of a second to decide whether they like the look of a website, researchers say.

Dr Gitte Lindgaard and colleagues from Carleton University in Ottawa flashed up websites for 50 milliseconds and asked participants to rate them for visual appeal.

When they repeated the exercise after a longer viewing period, the participants' ratings were consistent.

"Visual appeal can be assessed within 50 milliseconds, suggesting that web designers have about 50 milliseconds to make a good impression,"

the Canadians report in the journal Behaviour & Information Technology.

Associate Professor of psychology Bill von Hippel, from the University of New South Wales, says it takes about 50 milliseconds to read one word, making this a "stunningly remarkable" timeframe in which to process the complex stimuli on a website.

"It's quite remarkable that people do it that fast and that it holds up in their later judgement," he said.

"This may be because we have an affective or emotional system that [works] independently of our cognitive system."

He says that in evolutionary terms, this ability helped us respond rapidly to dangerous situations.

full article at ABC News

Wednesday, October 03, 2007

SIFT is the core of PhotoSynth

PhotoSynth underlying "magic" is using SIFT (Scale Invariant Feature Transform)

quoting Seitz
"We use a feature-matching technique called SIFT, developed by David Lowe at the University of British Columbia, that handles very significant differences in lighting, shading, weather, scale, and so forth,"

David Lowe's Autostitch project.

more SIFT implementations and source code