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.
Requirements
All code in this package requires the OpenCV library (known working
version is 2.3):
http://sourceforge.net/projects/opencvlibrary/
Some functions require GDK/GTK+2 (known working version is 2.18.4):
http://www.gtk.org/
Building
To build everything, use make:
make
This should produce a few executables in bin/, a static library
lib/libopensift.a, and some HTML documentation in docs/. You can use the -h
argument to get help with any of the executables. libopensift.a can be
compiled into your own code using the standard method:
gcc -I/path/to/opensift/include/ -L/path/to/opensift/lib/ yourcode.c -o yourexecutable -lopensift
The documentation in docs/ describes all of the functions available in
libopensift.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 libopensift.a,
e.g.
make libopensift.a
License
See the file LICENSE for more information on the legal terms of the use
of this package.