diff --git a/modules/imgproc/include/opencv2/imgproc/imgproc.hpp b/modules/imgproc/include/opencv2/imgproc/imgproc.hpp index 3bd41c355..520dcb7ab 100644 --- a/modules/imgproc/include/opencv2/imgproc/imgproc.hpp +++ b/modules/imgproc/include/opencv2/imgproc/imgproc.hpp @@ -347,6 +347,11 @@ CV_EXPORTS Ptr createBoxFilter( int srcType, int dstType, Size ksi Point anchor=Point(-1,-1), bool normalize=true, int borderType=BORDER_DEFAULT); + +//! returns the Gabor kernel with the specified parameters +CV_EXPORTS_W Mat getGaborKernel( Size ksize, double sigma, double theta, double lambd, + double gamma, double psi=CV_PI*0.5, int ktype=CV_64F ); + //! type of morphological operation enum { MORPH_ERODE=CV_MOP_ERODE, MORPH_DILATE=CV_MOP_DILATE, MORPH_OPEN=CV_MOP_OPEN, MORPH_CLOSE=CV_MOP_CLOSE, diff --git a/modules/imgproc/src/gabor.cpp b/modules/imgproc/src/gabor.cpp new file mode 100644 index 000000000..5a81312f7 --- /dev/null +++ b/modules/imgproc/src/gabor.cpp @@ -0,0 +1,98 @@ +/*M/////////////////////////////////////////////////////////////////////////////////////// +// +// IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING. +// +// By downloading, copying, installing or using the software you agree to this license. +// If you do not agree to this license, do not download, install, +// copy or use the software. +// +// +// License Agreement +// For Open Source Computer Vision Library +// +// Copyright (C) 2000-2008, Intel Corporation, all rights reserved. +// Copyright (C) 2009-2012, Willow Garage Inc., all rights reserved. +// Third party copyrights are property of their respective owners. +// +// Redistribution and use in source and binary forms, with or without modification, +// are permitted provided that the following conditions are met: +// +// * Redistribution's of source code must retain the above copyright notice, +// this list of conditions and the following disclaimer. +// +// * Redistribution's in binary form must reproduce the above copyright notice, +// this list of conditions and the following disclaimer in the documentation +// and/or other materials provided with the distribution. +// +// * The name of the copyright holders may not be used to endorse or promote products +// derived from this software without specific prior written permission. +// +// This software is provided by the copyright holders and contributors "as is" and +// any express or implied warranties, including, but not limited to, the implied +// warranties of merchantability and fitness for a particular purpose are disclaimed. +// In no event shall the Intel Corporation or contributors be liable for any direct, +// indirect, incidental, special, exemplary, or consequential damages +// (including, but not limited to, procurement of substitute goods or services; +// loss of use, data, or profits; or business interruption) however caused +// and on any theory of liability, whether in contract, strict liability, +// or tort (including negligence or otherwise) arising in any way out of +// the use of this software, even if advised of the possibility of such damage. +// +//M*/ + +#include "precomp.hpp" + +/* + Gabor filters and such. To be greatly extended to have full texture analysis. + For the formulas and the explanation of the parameters see: + http://en.wikipedia.org/wiki/Gabor_filter +*/ + +cv::Mat cv::getGaborKernel( Size ksize, double sigma, double theta, + double lambd, double gamma, double psi, int ktype ) +{ + double sigma_x = sigma; + double sigma_y = sigma/gamma; + int nstds = 3; + int xmin, xmax, ymin, ymax; + double c = cos(theta), s = sin(theta); + + if( ksize.width > 0 ) + xmax = ksize.width/2; + else + xmax = std::max(fabs(nstds*sigma_x*c), fabs(nstds*sigma_y*s)); + + if( ksize.height > 0 ) + ymax = ksize.height/2; + else + ymax = std::max(fabs(nstds*sigma_x*s), fabs(nstds*sigma_y*c)); + + xmin = -xmax; + ymin = -ymax; + + CV_Assert( ktype == CV_32F || ktype == CV_64F ); + + Mat kernel(ymax - ymin + 1, xmax - xmin + 1, ktype); + double scale = 1/(2*CV_PI*sigma_x*sigma_y); + double ex = -0.5/(sigma_x*sigma_x); + double ey = -0.5/(sigma_y*sigma_y); + double cscale = CV_PI*2/lambd; + + for( int y = ymin; y <= ymax; y++ ) + for( int x = xmin; x <= xmax; x++ ) + { + double xr = x*c + y*s; + double yr = -x*s + y*c; + + double v = scale*exp(ex*xr*xr + ey*yr*yr)*cos(cscale*xr + psi); + if( ktype == CV_32F ) + kernel.at(ymax - y, xmax - x) = (float)v; + else + kernel.at(ymax - y, xmax - x) = v; + } + + return kernel; +} + + +/* End of file. */