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Surf Giving Weird Keypoints

I am attempting to simply run the SurfDetector on an image and am getting weird kepypoint results.

I am pulling full HD images from a Logitech c930 camera using OpenCV 2.4.9 on a Win8.1 64 bit machine using VS2012 C++/cli.

Here is the image of keypoints that results from running SurfDetector with a minHessian set at 400.image description

alt text

As you can see, the kepypoints are all over the place and are do not appear to correspond to anything in particular. I tried setting the minHessian value at 100 also with no apparent effect.

The code that gets this result looks like:

 cvtColor(OriginalImage,GrayImage,CV_BGR2GRAY);
 SurfDetector->detect(GrayImage,tSurfKeypoints);
 drawKeypoints( OriginalImage,tSurfKeypoints,OriginalImage, Scalar::all(-1), DrawMatchesFlags::DEFAULT );

Is this right? It does not seem like it could be.

Any help appreciated.

Regards,

James

Surf Giving Weird Keypoints

I am attempting to simply run the SurfDetector on an image and am getting weird kepypoint results.

I am pulling full HD images from a Logitech c930 camera using OpenCV 2.4.9 3.0 on a Win8.1 64 bit machine using VS2012 C++/cli.

Here is the image of keypoints that results from running SurfDetector with a minHessian set at 400.image description

alt text

As you can see, the kepypoints are all over the place and are do not appear to correspond to anything in particular. I tried setting the minHessian value at 100 also with no apparent effect.

The code that gets this result looks like:

 cvtColor(OriginalImage,GrayImage,CV_BGR2GRAY);
 SurfDetector->detect(GrayImage,tSurfKeypoints);
 drawKeypoints( OriginalImage,tSurfKeypoints,OriginalImage, Scalar::all(-1), DrawMatchesFlags::DEFAULT );

Is this right? It does not seem like it could be.

By contrast, using the same images, FAST gives the following result:

image description

That seems more like what I would expect.

Any help appreciated.

Regards,

James