need atleast 4 corresponding points to calculate homography

aitikgupta · aitikgupta · commit 94e0ac7d9f9e · 2020-09-29T01:04:01.000+05:30
diff --git a/modules/calib3d/src/fundam.cpp b/modules/calib3d/src/fundam.cpp
@@ -374,6 +374,9 @@ cv::Mat cv::findHomography( InputArray _points1, InputArray _points2,
                 return Mat();
             convertPointsFromHomogeneous(p, p);
         }
+        // Need at least 4 point correspondences to calculate Homography
+        if( npoints < 4 )
+            CV_Error(Error::StsVecLengthErr , "The input arrays should have at least 4 corresponding point sets to calculate Homography");
         p.reshape(2, npoints).convertTo(m, CV_32F);
     }
 

Original file line number	Diff line number	Diff line change
`@@ -374,6 +374,9 @@ cv::Mat cv::findHomography( InputArray _points1, InputArray _points2,`
`374`	`374`	`return Mat();`
`375`	`375`	`convertPointsFromHomogeneous(p, p);`
`376`	`376`	`}`
	`377`	`+ // Need at least 4 point correspondences to calculate Homography`
	`378`	`+ if( npoints < 4 )`
	`379`	`+ CV_Error(Error::StsVecLengthErr , "The input arrays should have at least 4 corresponding point sets to calculate Homography");`
`377`	`380`	`p.reshape(2, npoints).convertTo(m, CV_32F);`
`378`	`381`	`}`
`379`	`382`