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a function from R2 to R (mapping space to light)
a set of pixels (what’s a pixel?)
an array of numbers
a JPEG file
a collection of regions, shapes, or features
a graph
à
answer depends on what you want to *do* with it!
As opposed to [0..255]
demo with scanalyze on laptop
color->monochrome
contrast
g(x,y) = f(2x, y)
Then, how about ty = -y/3?
show image morphing applet:
http://www.colonize.com/warp/
Salt and pepper and impulse noise can be due to transmission errors (e.g., from deep space probe), dead CCD pixels, specks on lens
Answer:
take lots of images, average them
Replace each pixel with the average of a kxk window around it
Replace each pixel with the average of a kxk window around it
Replace each pixel with the average of a kxk window around it
Replace each pixel with the average of a kxk window around it
What happens if we use a larger filter window?
Demo with photoshop
ones, divide by 9
photoshop demo
Q1:
They are the same for filters that have both horizontal and vertical symmetry.
Q2:
H
How to handle finite filters?
Better at salt’n’pepper noise
Not convolution: try a region with 1’s and a 2, and then 1’s and a 3