Questions tagged [surf]

Speeded-Up Robust Features (SURF) is a feature detection algorithm used in many [tag:computer-vision] tasks, such as object recognition, 3D reconstruction, camera calibration, and [tag:cbir].

Speeded-Up Robust Features (SURF) is an algorithm in computer vision to detect and describe local features in images.

SURF is billed as specifically “Speeded-Up” and “Robust” over its predecessor, the SIFT algorithm – it is based on Hessian blob detection, and eschews the more byzantine arrangements of SIFT (e.g. octaves). This visualization illustrates SURF features with circles, scaled accordingly for each feature, overlaid on the image from which they were extracted:

SURF feature overlaid

The standard standard SURF implementation, from the introductory journal article, is about an order of magnitude faster than David Lowe’s implementation of SIFT (when run in a comparable environment).

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Differences between OpenCV SURF and OpenSURF?

I am trying to use (SURF(opencv); [OPENSURF c++;OPENSURFC#] OPensurf http://www.chrisevansdev.com/computer-vision-opensurf.html), SIFT for image matching. I have the feeling that SIFT is more accurate at the time of cost than…
Shahgee
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Homography, inliers/ Emgu CV/ SURF in C#

How can I get inliers/outliers of matched kyepoints using homography or some other method in C#? I am working on SURF example provided on http://www.emgu.com/wiki/index.php/SURF_feature_detector_in_CSharp. I got matchedFeature. Code uses…
Shahgee
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OpenCV Python/C++: Feature Matching in Images with different Lighting, etc

I am trying to detect and match features in two sets of images of the same scene from different sources (and different lighting, contrast etc.). For now I've tried various different feature detection/description methods (SURF, SIFT, ORB) as well as…
flhp
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module object has no attribute 'DescriptorExtractor_create()'

I installed opencv3.1.0 with opencv_contrib correctly installed but I am getting the error no module 'DescriptorExtractor_create()' and everything is fine. Suggestions??? :)
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Matlab - Subtracting two 3D figures with surf and min function

I'm trying to make a surf plot that looks like: So far I have: x = [-1:1/100:1]; y = [-1:1/100:1]; [X,Y] = meshgrid(x,y); Triangle1 = -abs(X) + 1.5; Triangle2 = -abs(Y) + 1.5; Z = min(Triangle1, Triangle2); surf(X,Y,Z); shading flat colormap…
Ahmed Abdelazim
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What is the difference between layers and octaves in SIFT/SURF?

I read both Lowe's papers ('99&'04) and I would say I understood most of them. I saw all SIFT related classes on youtube, but none explicitly says why we would use both octaves and layers? I understood that you get more layers in the same octave by…
Andrei
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Image recognition using SURF with OpenCV in Android

I'm trying to build a simple leaf recognition app with Android and OpenCV; my database consist in just 3 entries (3 pictures of 3 types of leaves) and I would like to be able to recognise if one of the pictures in the database is inside another…
Nicholas Allio
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OpenCV SURF, is it normal that the captured videos lag by a little? How to speed it up?

How do I speed up the correspondence matching processes of SURF? I used the samples provided and changed it to capture color images from the webcam for processing, however, the speed certainly needs improvement. Where should this be tackled on?
yasumi
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OpenCV 3.0.0 SurfFeatureDetector and SurfDescriptorExtractor Errors

I am attempting to implement the OpenCV 3.0.0 SURF Feature Description and Detection but after running the sample code on the OpenCV site, I receive a load of errors all related to SURF. Any idea of what could be going wrong? Thanks! #include…
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OpenCV Python: Occasionally get segmentation fault when using FlannBasedMatcher

I'm trying to classify objects using SURF and kNN. The code work well however it occasionally crashes and shows 'Segmentation Fault'. I'm not sure whether I did something wrong but I'm pretty sure that it is corrected. Here is the input file in case…
Nuntipat Narkthong
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OpenCV traffic sign recognition

I'm coding a software (for my studies) for traffic sign recognition with an IP Camera.For a moment, I have to recognise traffic signs like this: In my code, I'm doing a high transformation to isolate my traffic sign with a mask. Then, I do a SURF…
Mickaël B.
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How to train OpenCV SVM with BoW Properly

I can't train the SVM to recognize my object. I'm trying to do this using SURF + Bag Of Words + SVM. My problem is that the classifier does not detect anything. All the results are 0. Here is my code: Ptr detector =…
dephinera
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OpenCV - match SURF points runtime error

I have a program which matches feature points found in a template image to those shown in the video feed. When I run the program I am getting the following error: OpenCV Error: Assertion failed (i1 >= 0 && i1 < static_cast(keypoints1.size()))…
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OpenCV SURF - Get Rotation angle between two images

I am using the SURF algorithm for comparing landmarks between objects, and am wondering how to detect the rotation angle between the two pictures. I have already seen the another question very similar. This question was turned down for being a naive…
The_Doctor
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nonfree (SIFT, SURF) usage in android with java

I am having trouble with nonfree methdos usage in android. SIFT and SURF methods are not included in opencv-android-2.4.8. They are needed to be complied seperately.…
fetifati
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