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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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optimum hessian threshold for SURF feature extraction in opencv + Minimum descriptors matching

Currently I am working on face recognition project where I am using Fisherfaces/LDA to filter out the images on a broader level and then using SURF to verify the output from LDA. What would be a good Hessian threshold which should be passed to…
ahirnish
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SURF description faster with FAST detection?

for my master thesis, i am running some test on the SIFT SURF en FAST algoritms for logo detection on smartphones. when i simply time the detection, description en matching for some methods i get the following results. For a SURF detector and SURF…
piepie
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Compare SURF descriptors in one image to a list of descriptors in other images

I want to compare the SURF descriptors in one image (A), with the descriptors in several other images (B,C,D,..) to find the most similar image to A. The descriptors have 64 dimensions. Using C# and Emgu, the match is done by comparing A's…
MortenGR
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How to load big dataset from CSV into keras

I'm trying to use Keras with TensorFlow to train a network based on the SURF features that I obtained from several images. I have all this features stored in a CSV file that has the following columns: [ID, Code, PointX, PointY, Desc1, ...,…
Tomas Perez Cambet
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Weird result with SURF comparison

I'm trying to implement a traffic sign recognizer with OpenCV and SURF method. My problem is that i get random results (sometimes really accurate, sometimes obviously wrong) and i cant undertsand why. Here is how i implemented the comparison…
vdaubry
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Python - Displaying the image with the original colors

In the answer to this question, I wanted to display the image in its original colors, and so removed the gray parameter from this line of code: plt.imshow(im_out, 'gray') When doing this however I get the image displayed with yellow and purple…
Simplicity
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How to draw (semi-)logarithmic 3d plots? (Matlab)

I know semilogx and semilogy for 2D plots. There is any equivalent for SURF and MESH?
Jader Dias
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Detect more than 1 object on picture

I wrote a little script which let to find an object in a global picture by the SIFT descriptors method. But I have a question about multiple detections in the same picture. I have this global picture : I have this template : My script looks like…
Essex
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A good method for detecting the presence of a particular feature in an image

I have made a videochat, but as usual, a lot of men like to ehm, abuse the service (I leave it up to you to figure the nature of such abuse), which is not something I endorse in any way, nor do most of my users. No, I have not stolen…
Armen Michaeli
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knnMatch with k = 2 returns 0 nearest-neighbour even with images trained

I am basically extracting many keypoints with SURF from similar images and adding them to the BFMatcher(NORM_L2) In runtime It can happen that I add new keypoints to my matcher with matcher->add(myNewDescriptors); Now when I have added an image with…
dynamic
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OpenCV: Extract SURF Features from user-defined keypoints

I want to compute SURF Features from keypoints that I specify. I am using the Python wrapper of OpenCV. The following is the code I am trying to use, but I cannot find a working example anywhere. surf = cv2.SURF() keypoints, descriptors =…
hjweide
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Why we need crossCheckMatching for feature?

I am reading lot of post for object detection using feature extraction (sift ecc). After having calculate descriptors on both images, to get good matches they are using crossCheckMatching. (found on…
dynamic
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OpenCV matching images

I am trying to use OpenCV to match images like these: img2 http://img849.imageshack.us/img849/8177/clearz.jpg And I need to find the best intersection of them. I tried using SURFDetector and matching using BruteforceMatcher, but finds descriptors…
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SURF interest point parameters

I want to give alternative interest points as input to SURF using the -p1 command (I'm using the authors implementation: http://www.vision.ee.ethz.ch/~surf/download.html). But I'm not sure what to make of the parameters. I need to give x,y,a,b,c…
Bart
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How to match and align two images using SURF features (Python OpenCV )?

I am using following code for matching surf features of the two images but unable to crop and align the image. The original image，the rotated image and matched image are as follow. I want to straight the rotated image just like the original image…
Muhammad Danial Khan
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