1. Intro
2. Requirements
3. Building
4. License

1. Intro

This is a collection of code I've put together to detect SIFT features 
in images and to use SIFT (or other) features to compute image 
transforms with RANSAC. It includes a SIFT function library as well as 
some executables to detect, match, and display keypoints. For more 
information on SIFT, refer to the paper by Lowe:

Lowe, D. Distinctive image features from scale-invariant keypoints. 
International Journal of Computer Vision, 60, 2 (2004), pp.91--110.

Or see Lowe's website:
http://www.cs.ubc.ca/~lowe/keypoints/

Some of the code also works with affine-invariant features from the code 
by the VGG at oxford:
http://www.robots.ox.ac.uk:5000/~vgg/research/affine/index.html

Check out match.c for an example of how to use the RANSAC function.  Try 
`match beaver.png beaver_xform.png` to see it work.

Documentation is included in the docs/ directory.  If it is not there, 
use `make docs` to build it (you need Doxygen).

Help is available for executables using the '-h' command line option.

/***************************************************************************/

2. Requirements

All code in this package requires the OpenCV library (known working 
version is 1.0.0):
http://sourceforge.net/projects/opencvlibrary/

Some functions require GDK/GTK+2 (known working version is 2.10.14):
http://www.gtk.org/

Some functions require the Gnu Scientific Library (GSL) (known working 
version is 1.9):
http://www.gnu.org/software/gsl/

/***************************************************************************/

3. Building

To build everything, use make:

> make

This should produce a few executables in bin/, a static library 
lib/libfeat.a, and some HTML documentation in docs/.  You can use the -h 
argument to get help with any of the executables.  libfeat.a can be 
compiled into your own code using the standard method:

> gcc -I/path/to/sift/include/ -L/path/to/sift/lib/ yourcode.c	\
	-o yourexecutable -lfeat

The documentation in docs/ describes all of the functions available in 
libfeat.a as well as #defines, etc.  Use the documentation to determine 
what header files from include/ to include in your code.

You can also individually build any of the executables or libfeat.a, 
e.g.

> make libfeat.a

/***************************************************************************/

4. License

The SIFT algorithm is Patented in the U.S. by the University of British 
Columbia. Thus, the SIFT feature detection code in this package may not 
be used in any commercial products without permission from UBC. All 
other code in this package is Licensed under the GPLv2. See the files 
LICENSE.ubc and LICENSE for more info. 
