CS 7321: Computer Vision I

In addition, we will also learn to use some other tools for this PS.

Capture an Image:

SGI/Indy with an IndyCam (in 130 CoC)

Use the command "capture". It will open up a small window with output from the indycam and a trivial User Interface

If there is nothing appearing on the window, check for trivial thinks like lens cap (DOH!). Also from the "tools" open the "video panel" for more controls and options on what signal to use.

During our class session, I will bring a better color camera.

HPs (in 311 CoC [not 304, as previously stated])

Check out a camera from the TA and attach it to the Parallax board's Video Input. There are applications in "/opt/parallax" that allow you capture images.

Since the HP Imaging Lab (311 CoC) is not fully available to us for a week, maybe the best would be not to worry about using it for this PS.

Any other system If you know of any other way of capturing images, more power to you.

The aim here is to digitize a good quality color and gray scale images, including one of your face with your face well framed in the image (see the WWW pages for an example ).

Convert an image to MATLAB readable form

Matlab can take images in TIFF, JPEG, X, or RAW format. So the best thing to do is to convert your image to one of these formats.

SGI/Indy (in 130 CoC)

The capture program on an SGI Indy saves a color image in SGI RGB format. To convert it to GIF use program called "imgworks".

Using imgworks save the image as a TIFF file.

For HPs or Other platforms Figure out how to save the image as a TIFF file.

MATLAB

1. Start matlab (typing "matlab (matlab51 on SGIs)" on a shell should do it).
• Play around for a while.
• Try to understand the signaificance of variables.
• type demos
• type imagedemo
• type imdemo
• play around as much as possible.
• Commads to remember: "help", "help matlab/general", "lookfor"
• type docs in matlab or matlabdocs on unix
• check out mathworks web page  www.mathworks.com
2. load your image using "tiffread" (see help tiffread). Read in [R G B] values OR [X, map]
3. convert image to a grayscale image (hint: "lookfor gray")  (You can also do this on UNIX)
4. Figure out how to crop this image. Crop it so as to perfectly frame your face.
5. run "imdemo" and find functions that interest you.
6. try them out on your image
7. Figure out how to save these images (hint: "lookfor write")

The orignal image should be "face.gif", while the resulting few images should be named "face1.gif", "face2.gif", ... etc.
 

OTHER STUFF

Acquire other images, either from the WWW or using the camera.

For Matlab Experts

• Rewrite the imdemo function to include your image and also of your fellow classmates.   Use some filtering and ROI functions (see roidemo).

What to hand in ?

• Hand in a page with your image and different versions of the same image after you have played around with it in Matlab.
• I would like for you to also generate an HTML document showing your experiments.
• I have a complete template of this available at  http://www.cc.gatech.edu/classes/cs7321_98_winter/u/irfan/ps0/.  On the CoC file system this file is located at /net/www/classes/cs7321_98_winter/u/irfan/ps0/index.html.
• You should also have a directory under /net/www/classes/cs7321_98_winter/participants/[your-coc-login]/
• Copy the ps0 directory from my directory to yours and edit to show your results.

More specific CoC account questions shoule be sent to help@cc.gatech.edu . 

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