Add template match with mask.

Signed-off-by: Yan Wang <yan.wang@linux.intel.com>

modules/imgproc/include/opencv2/imgproc.hpp

@@ -3330,9 +3330,11 @@ data type.
 @param result Map of comparison results. It must be single-channel 32-bit floating-point. If image
 is \f$W \times H\f$ and templ is \f$w \times h\f$ , then result is \f$(W-w+1) \times (H-h+1)\f$ .
 @param method Parameter specifying the comparison method, see cv::TemplateMatchModes
+@param mask Mask of searched template. It must have the same datatype and size with templ. It is
+not set by default.
  */
 CV_EXPORTS_W void matchTemplate( InputArray image, InputArray templ,
-                                 OutputArray result, int method );
+                                 OutputArray result, int method, InputArray mask = noArray() );
 
 //! @}
 

modules/imgproc/src/templmatch.cpp

@@ -814,12 +814,97 @@ void crossCorr( const Mat& img, const Mat& _templ, Mat& corr,
         }
     }
 }
+
+static void matchTemplateMask( InputArray _img, InputArray _templ, OutputArray _result, int method, InputArray _mask )
+{
+    int type = _img.type(), depth = CV_MAT_DEPTH(type), cn = CV_MAT_CN(type);
+    CV_Assert( CV_TM_SQDIFF <= method && method <= CV_TM_CCOEFF_NORMED );
+    CV_Assert( (depth == CV_8U || depth == CV_32F) && type == _templ.type() && _img.dims() <= 2 );
+
+    Mat img = _img.getMat(), templ = _templ.getMat(), mask = _mask.getMat();
+    int ttype = templ.type(), tdepth = CV_MAT_DEPTH(ttype), tcn = CV_MAT_CN(ttype);
+    int mtype = img.type(), mdepth = CV_MAT_DEPTH(type), mcn = CV_MAT_CN(mtype);
+
+    if (depth == CV_8U)
+    {
+        depth = CV_32F;
+        type = CV_MAKETYPE(CV_32F, cn);
+        img.convertTo(img, type, 1.0 / 255);
+    }
+
+    if (tdepth == CV_8U)
+    {
+        tdepth = CV_32F;
+        ttype = CV_MAKETYPE(CV_32F, tcn);
+        templ.convertTo(templ, ttype, 1.0 / 255);
+    }
+
+    if (mdepth == CV_8U)
+    {
+        mdepth = CV_32F;
+        mtype = CV_MAKETYPE(CV_32F, mcn);
+        compare(mask, Scalar::all(0), mask, CMP_NE);
+        mask.convertTo(mask, mtype, 1.0 / 255);
+    }
+
+    Size corrSize(img.cols - templ.cols + 1, img.rows - templ.rows + 1);
+    _result.create(corrSize, CV_32F);
+    Mat result = _result.getMat();
+
+    Mat img2 = img.mul(img);
+    Mat mask2 = mask.mul(mask);
+    Mat mask_templ = templ.mul(mask);
+    Scalar templMean, templSdv;
+
+    double templSum2 = 0;
+    meanStdDev( mask_templ, templMean, templSdv );
+
+    templSum2 = templSdv[0]*templSdv[0] + templSdv[1]*templSdv[1] + templSdv[2]*templSdv[2] + templSdv[3]*templSdv[3];
+    templSum2 += templMean[0]*templMean[0] + templMean[1]*templMean[1] + templMean[2]*templMean[2] + templMean[3]*templMean[3];
+    templSum2 *= ((double)templ.rows * templ.cols);
+
+    if (method == CV_TM_SQDIFF)
+    {
+        Mat mask2_templ = templ.mul(mask2);
+
+        Mat corr(corrSize, CV_32F);
+        crossCorr( img, mask2_templ, corr, corr.size(), corr.type(), Point(0,0), 0, 0 );
+        crossCorr( img2, mask, result, result.size(), result.type(), Point(0,0), 0, 0 );
+
+        result -= corr * 2;
+        result += templSum2;
+    }
+    else if (method == CV_TM_CCORR_NORMED)
+    {
+        if (templSum2 < DBL_EPSILON)
+        {
+            result = Scalar::all(1);
+            return;
+        }
+
+        Mat corr(corrSize, CV_32F);
+        crossCorr( img2, mask2, corr, corr.size(), corr.type(), Point(0,0), 0, 0 );
+        crossCorr( img, mask_templ, result, result.size(), result.type(), Point(0,0), 0, 0 );
+
+        sqrt(corr, corr);
+        result = result.mul(1/corr);
+        result /= std::sqrt(templSum2);
+    }
+    else
+        CV_Error(Error::StsNotImplemented, "");
+}
 }
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////////
 
-void cv::matchTemplate( InputArray _img, InputArray _templ, OutputArray _result, int method )
+void cv::matchTemplate( InputArray _img, InputArray _templ, OutputArray _result, int method, InputArray _mask )
 {
+    if (!_mask.empty())
+    {
+        cv::matchTemplateMask(_img, _templ, _result, method, _mask);
+        return;
+    }
+
     int type = _img.type(), depth = CV_MAT_DEPTH(type), cn = CV_MAT_CN(type);
     CV_Assert( CV_TM_SQDIFF <= method && method <= CV_TM_CCOEFF_NORMED );
     CV_Assert( (depth == CV_8U || depth == CV_32F) && type == _templ.type() && _img.dims() <= 2 );

samples/cpp/mask_tmpl.cpp

@@ -0,0 +1,72 @@
+#include "opencv2/imgproc.hpp"
+#include "opencv2/highgui.hpp"
+
+#include <cctype>
+#include <iostream>
+#include <iterator>
+#include <stdio.h>
+
+using namespace std;
+using namespace cv;
+
+static void help()
+{
+    cout << "\nThis program demonstrates template match with mask.\n"
+            "Usage:\n"
+            "./mask_tmpl <image_name> <template_name> <mask_name>, Default is ../data/lena_tmpl.jpg\n"
+            << endl;
+}
+
+int main( int argc, const char** argv )
+{
+    const char* filename = argc == 4 ? argv[1] : "../data/lena_tmpl.jpg";
+    const char* tmplname = argc == 4 ? argv[2] : "../data/tmpl.png";
+    const char* maskname = argc == 4 ? argv[3] : "../data/mask.png";
+
+    Mat img = imread(filename);
+    Mat tmpl = imread(tmplname);
+    Mat mask = imread(maskname);
+    Mat res;
+
+    if(img.empty())
+    {
+        help();
+        cout << "can not open " << filename << endl;
+        return -1;
+    }
+
+    if(tmpl.empty())
+    {
+        help();
+        cout << "can not open " << tmplname << endl;
+        return -1;
+    }
+
+    if(mask.empty())
+    {
+        help();
+        cout << "can not open " << maskname << endl;
+        return -1;
+    }
+
+    //int method = CV_TM_SQDIFF;
+    int method = CV_TM_CCORR_NORMED;
+    matchTemplate(img, tmpl, res, method, mask);
+
+    double minVal, maxVal;
+    Point minLoc, maxLoc;
+    Rect rect;
+    minMaxLoc(res, &minVal, &maxVal, &minLoc, &maxLoc);
+
+    if(method == CV_TM_SQDIFF || method == CV_TM_SQDIFF_NORMED)
+        rect = Rect(minLoc, tmpl.size());
+    else
+        rect = Rect(maxLoc, tmpl.size());
+
+    rectangle(img, rect, Scalar(0, 255, 0), 2);
+
+    imshow("detected template", img);
+    waitKey();
+
+    return 0;
+}