September 2008
Beginner to intermediate
580 pages
20h 7m
English
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Exercises
Generate 1,000 random numbers ri between 0 and 1. Decide on a bin size and then take a histogram of 1/ri.
Are there similar numbers of entries (i.e., within a factor of ±10) in each histogram bin?
Propose a way of dealing with distributions that are highly nonlinear so that each bin has, within a factor of 10, the same amount of data.
Take three images of a hand in each of the three lighting conditions discussed in the text. Use
cvCalcHist()to make an RGB histogram of the flesh color of one of the hands photographed indoors.Try using just a few large bins (e.g., 2 per dimension), a medium number of bins (16 per dimension) and many bins (256 per dimension). Then run a matching routine (using all histogram matching methods) against the other indoor lighting images of hands. Describe what you find.
Now add 8 and then 32 bins per dimension and try matching across lighting conditions (train on indoor, test on outdoor). Describe the results.
As in exercise 2, gather RGB histograms of hand flesh color. Take one of the indoor histogram samples as your model and measure EMD (earth mover's distance) against the second indoor histogram and against the first outdoor shaded and first outdoor sunlit histograms. Use these measurements to set a distance threshold.
Using this EMD threshold, see how well you detect the flesh histogram of the third indoor histogram, the second outdoor shaded, and the second outdoor sunlit histograms. Report your results.
Take histograms of randomly chosen nonflesh ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.