Assignment 2 for CSE 130/DXARTS 198A
Spring Quarter, 2008
Type your answers into a plain text file.
(If you want to, type them into a Microsoft
Word document that uses only one font and text
size and style; then save the file as plain text -- .txt).
Turn in your file by uploading it to our CollectIt dropbox
and submitting it as Assignment 2.
The dropbox is
at the UW Catalyst web site, linked from here.
Part 1
Do all exercises at the end of Chapter 2.
Part 2
(Something more creative and open-ended.)
A.
Upload an image of your choice to the INFACT
file management facility on Socrates.
To upload an image, from the main INFACT page,
select the link "Manage Files", and then use the
"Browse" button and "Upload" button to select and
upload your image file.
The image should
be something you wouldn't mind sharing with the
rest of the class.
After you have uploaded the image, answer the
question: What file name did you give your image?
B.
Identify some key feature in the image that
you will try to keep recognizable, such as the
number of trees in front of the house, the fact
that there is a person in the picture, etc.
Then use PixelMath to produce a minimum-resolution
version of that image in which that feature is
still recognizable. Explain this minimum resolution
in terms of Nyquist sampling.
C.
Create a high-contrast monochrome version of
your image. The result should be an image with only
black pixels and white pixels.
(Work from the original high-resolution version of
the image --- not the result from Part B.)
Try to maximize either the clarity
of the representation or the aesthetic appeal of it.
Explain both what operations you performed and how
you chose them.
D.
Create a re-colored version of the image by
applying a PixelMath formula that alters the colors
of the pixels. Try to come up with a formula that
makes the resulting image visually most interesting.
Note that one convenient type of formula for
such a task involves a call to calculator function "RGB".
For example,
RGB(Green1(x,y), Blue1(x,y), Red1(x,y))
performs a sort of "rotation" of the color components,
so that the amount of green in a pixel becomes the amount
of red in the pixel, and the amount of blue becomes the
amount of green, and the amount of red becomes the amount
of blue.
You may also choose to work with formulas involving
hue, saturation, and value of the colors.
When you are satisfied with your formula,
write that down as your answer, and then describe
either what you were trying to do or what you did
as you created it.
Solutions prepared by Cam.