This  code has  been  presented for  the demo  :  "Tracking texture-less,  shiny
objects with descriptor fields." Mixed  and Augmented Reality (ISMAR), 2014 IEEE
International Symposium on. IEEE, 2014.

It allows  to track homographies using  the descriptor fields introduced  in our
CVPR paper:

[1] Crivellaro Alberto and Vincent  Lepetit. "Robust 3D Tracking with Descriptor
    Fields.", CVPR 2014

Please cite [1] if you make use of this code.

Authors: 
	 Alberto Crivellaro 
	 Yannick Verdie
	 Kwang Moo Yi
	 Pascal Fua
	 Vincent Lepetit

For questions or comments please write to :
    	      
	 alberto<dot>crivellaro<at>epfl<dot>ch


================================================================================
BUILDING: 

The software  has been tested and  successfully run in  real time (> 30  fps) on
linux Ubuntu  14.04 on a  MacBookPro i7 2.30GHz. It  was built with  gcc-4.9 and
openmp 4.0. We also tested on MacOS  with clang (no openmp) and we also obtained
good performance  (~20fps).  Older  versions of gcc/openmp  could lead  to worse
performances.


Prior  to  build the  code  you  should install  the  (latest  version of  the)
following dependencies:

   - opencv (we tested with 2.4.9 and 3.0)
   - eigen 3 or more

Moreover,  you   should  correctly  configure  your   LD_LIBRARY_PATH  and  your
PKG_CONFIG_PATH. For building just 'make all’.  The build produces :

   - libC++/libHomographyEstimation.so  : a  C++ dynamic  library for  computing
     descriptor fields  out of a  grayscale image, for computing  the homography
     between 2 images and several utilities for display, I/O, etc.

   - ISMAR_Demo/homographyDemo  :  an executable  for  performing  real time  3D
     tracking of planar surfaces., it links to the c++ library and can be use as
     example to understand how to link to the library.

   - unit/unittests : some tests


================================================================================
EXECUTING THE DEMO:

./homographyDemo  <camera_device_number> 

you should  initialize the template  putting a planar  surface in front  of the
camera (covering at least  all the region in the black  rectangle on the image),
and then press:

    1 for tracking using image intensities
    2 for tracking using gradient magnitude
    3 for tracking using descriptor fields

The             optimization            parameters             are            in
ISMAR_Demo/parameter/parameters*****Optimization.yml files. You  can change them
for attempting to achieve a better stability.



================================================================================
USING THE LIBRARY FOR YOUR PROJECTS: 

include   libC++/HomographyEstimation.hpp   in   your  code,   and   link   with
libHomographyEstimation.so  .   For  examples  on   how  to  use  the  different
utilities, you can take a look at the unit tests, more in particular :

    void LucaskanadeSSDTest();
    void LucaskanadeDescriptorFieldsTest();
    void LucaskanadeVideoSSDSpeedTest();
    void LucaskanadeVideoDesciptorFieldsSpeedTest();
    void LucaskanadeVideoGradientMagnitudeSpeedTest();



================================================================================
USEFUL LINKS:

homepage of the project: http://cvlab.epfl.ch/page-107683-en.html 
demonstration video: 	 https://www.youtube.com/watch?v=r-WJDM6HyAs