Merge pull request opencv#10258 from savuor:fix/kmeans_channels

savuor · alalek · commit bab86d65cb0f · 2017-12-15T21:48:48.000+03:00
* kmeans: number of channels in _centers fixed

* fixedType() is checked now
diff --git a/modules/core/src/kmeans.cpp b/modules/core/src/kmeans.cpp
@@ -458,7 +458,12 @@ double cv::kmeans( InputArray _data, int K,
         {
             best_compactness = compactness;
             if( _centers.needed() )
-                centers.copyTo(_centers);
+            {
+                Mat reshaped = centers;
+                if(_centers.fixedType() && _centers.channels() == dims)
+                    reshaped = centers.reshape(dims);
+                reshaped.copyTo(_centers);
+            }
             _labels.copyTo(best_labels);
         }
     }
diff --git a/samples/cpp/kmeans.cpp b/samples/cpp/kmeans.cpp
@@ -37,7 +37,7 @@ int main( int /*argc*/, char** /*argv*/ )
         Mat points(sampleCount, 1, CV_32FC2), labels;
 
         clusterCount = MIN(clusterCount, sampleCount);
-        Mat centers;
+        std::vector<Point2f> centers;
 
         /* generate random sample from multigaussian distribution */
         for( k = 0; k < clusterCount; k++ )
@@ -65,9 +65,9 @@ int main( int /*argc*/, char** /*argv*/ )
             Point ipt = points.at<Point2f>(i);
             circle( img, ipt, 2, colorTab[clusterIdx], FILLED, LINE_AA );
         }
-        for (i = 0; i < centers.rows; ++i)
+        for (i = 0; i < (int)centers.size(); ++i)
         {
-            Point2f c = centers.at<Point2f>(i);
+            Point2f c = centers[i];
             circle( img, c, 40, colorTab[i], 1, LINE_AA );
         }
         cout << "Compactness: " << compactness << endl;

Original file line number	Diff line number	Diff line change
`@@ -458,7 +458,12 @@ double cv::kmeans( InputArray _data, int K,`
`458`	`458`	`{`
`459`	`459`	`best_compactness = compactness;`
`460`	`460`	`if( _centers.needed() )`
`461`		`- centers.copyTo(_centers);`
	`461`	`+ {`
	`462`	`+ Mat reshaped = centers;`
	`463`	`+ if(_centers.fixedType() && _centers.channels() == dims)`
	`464`	`+ reshaped = centers.reshape(dims);`
	`465`	`+ reshaped.copyTo(_centers);`
	`466`	`+ }`
`462`	`467`	`_labels.copyTo(best_labels);`
`463`	`468`	`}`
`464`	`469`	`}`
Original file line number	Diff line number	Diff line change
`@@ -37,7 +37,7 @@ int main( int /argc/, char** /argv/ )`
`37`	`37`	`Mat points(sampleCount, 1, CV_32FC2), labels;`
`38`	`38`
`39`	`39`	`clusterCount = MIN(clusterCount, sampleCount);`
`40`		`- Mat centers;`
	`40`	`+ std::vector<Point2f> centers;`
`41`	`41`
`42`	`42`	`/* generate random sample from multigaussian distribution */`
`43`	`43`	`for( k = 0; k < clusterCount; k++ )`
`@@ -65,9 +65,9 @@ int main( int /argc/, char** /argv/ )`
`65`	`65`	`Point ipt = points.at<Point2f>(i);`
`66`	`66`	`circle( img, ipt, 2, colorTab[clusterIdx], FILLED, LINE_AA );`
`67`	`67`	`}`
`68`		`- for (i = 0; i < centers.rows; ++i)`
	`68`	`+ for (i = 0; i < (int)centers.size(); ++i)`
`69`	`69`	`{`
`70`		`- Point2f c = centers.at<Point2f>(i);`
	`70`	`+ Point2f c = centers[i];`
`71`	`71`	`circle( img, c, 40, colorTab[i], 1, LINE_AA );`
`72`	`72`	`}`
`73`	`73`	`cout << "Compactness: " << compactness << endl;`