Spring 2010 - CS477/577 - An Introduction to Computer Vision

C/C++ support

Most assignments require capability that you do not want to implement yourself. Thus you have to link against libraries. I will provide my version of tools that you can use to do the assignments, but you can use other libraries if you prefer (but then you are on your own regarding making it work and providing a compilable program that works on the graphics machines).

The TA and I will provide some support for these as they are used for research and are in continual development. Note that these libraries are currently unix (including MacOS which is unix) only. If you want to minimize your use of unix, then perhaps best to use Matlab.

The needed include files, library archive, and supporting libraries are available for the various machines on the UA CS network. Using the precompiled library is described next. In addition, a read only SVN repository is available (described below) for those that want to work on a machine outside the CS network. However, for full functionality, you will likely have to install additional libraries.


Compiling and Linking an Example Program on a CS Machine

To get you started, there is an example program showing the use of a few functions here . There are hopefully enough comments in the code to get you started. The files

    build.csh (tcsh users)
or 
    build.sh (bash users)
provide command lines that deal with the complexities of including and linking for most machines on the CS network.

The files matrix.txt and image.tiff can be used as example data for the program.


Working with the source code

The above describes using the library as a "black box" provider of functionality. However, the library is actually designed to be used as part of a source tree, with the modules that are needed being compiled on demand. The reason for this choice is that much of the vision lab code development is at the library level. Hence for us, the library is just part of the source code, not an external entity. Using the library in the same way might be attractive to some, and is the best option for who want to work with it on computers not on the CS network.

Information on working with the vision lab library source code is available here.


Resources

Man pages (MANPATH is: ~kobus/doc/man (on most CS machines)

Also available in html at:     http://kobus.ca/research/resources/doc/kjb/KJB.html

Start with a "man kjb" or the above link. Note that the first part of the document is a bit overwhelming, as it is geared towards writing substantive vision components shared with the group and/or, writing code for the library itself. This document essentially gives you a template for the "INCLUDE AND LOAD" strategy described by "man kjb".

A key point is that "man kjb" gives a machine generated list of all routines which have at least minimal documentation. (Perhaps 1/2 of the routines of interest are documented.)

Note that there are man pages for the main data types. In particular, you can do:

        man Vector
        man Matrix
        man KJB_image
        man Pixel
(Either click on the link or use the "man" command.)

Other documentation

There are some documentation files which attempt to explain some of the less conventional things about the library in the following directory:
        ~kobus/doc/programming
I wrote it a few years back. Hopefully it is not too out of date.

Finally, the vision lab has a wiki that has a lot more information (not necessarily well organized) linked here. You will need the password. Email the instructor if you would it.


Specific routines for assignment two

For assignment one you might want to look at the man pages for:

    read_matrix
    get_random_matrix
    multiply_matrices
    max_matrix_element
    ow_multiply_matrix_by_scalar
    ow_subtract_scalar_from_matrix
    ow_add_matrices
    
    plot_open
    plot_matrix_cols

    get_MP_inverse  

    constrained_least_squares    (grad students only)
(Either click on the link or use the "man" command.)

You will also want to use something like prompt_to_continue() so you (and the TA) can actually look at your plots. (This is used in the example program linked above).


Specific routines for assignment three

For assignment three you might want to look at the man pages for:

    multiply_by_transpose
    multiply_with_transpose
    diagonalize_symmetric
    KJB_image   (case sensitive; there is also a program kjb_image(1)).
    Pixel
    kjb_read_image
    kjb_write_image 
(Either click on the link or use the "man" command.)


Specific routines for assignment four

For assignment four you might want to look at the man pages for:

    least_squares     (OK now that you know how to do it).
    plot_open3
    plot_matrix_values
(Either click on the link or use the "man" command.)


Specific routines for assignment five

For assignment five you might want to look at the man pages for:

    kjb_read_image
    kjb_write_image
    kjb_display_image

    ow_make_black_and_white_image
    bw_image_to_matrix
    matrix_to_bw_image

    get_1D_gaussian_mask
    get_2D_gaussian_mask

    x_convolve_matrix
    y_convolve_matrix
    convolve_matrix

    init_cpu_time
    get_cpu_time
(Either click on the link or use the "man" command.)