From ed6e07160a5cb104311229624010d4789242f9f6 Mon Sep 17 00:00:00 2001
From: Victor Erukhimov <no@email>
Date: Thu, 10 Jun 2010 16:35:05 +0000
Subject: [PATCH] Added intro for detectors/descriptors interface

---
 doc/cv_feature_detection.tex | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/doc/cv_feature_detection.tex b/doc/cv_feature_detection.tex
index ee9807e69..c8dfdbdd0 100644
--- a/doc/cv_feature_detection.tex
+++ b/doc/cv_feature_detection.tex
@@ -1212,7 +1212,15 @@ There is fast multi-scale Hessian keypoint detector that can be used to find the
 The function can be used for object tracking and localization, image stitching etc. See the
 \texttt{find\_obj.cpp} demo in OpenCV samples directory.
 
-\subsection{Common Interfaces for Feature Detection and Descriptor Extraction}
+\section{Common Interfaces for Feature Detection and Descriptor Extraction}
+Both detectors and descriptors in OpenCV have wrappers with common interface that enables to switch easily 
+between different algorithms solving the same problem. All objects that implement keypoint detectors inherit 
+FeatureDetector interface. Descriptors that are represented as vectors in a multidimensional space can be 
+computed with DescriptorExtractor interface. DescriptorMatcher interface can be used to find matches between 
+two sets of descriptors. GenericDescriptorMatch is a more generic interface for descriptors. It does not make any 
+assumptions about descriptor representation. Every descriptor with DescriptorExtractor interface has a wrapper with 
+GenericDescriptorMatch interface (see VectorDescriptorMatch). There are descriptors such as one way descriptor and 
+ferns that have GenericDescriptorMatch interface implemented, but do not support DescriptorExtractor.
 
 \cvclass{FeatureDetector}
 Abstract base class for 2D image feature detectors.