The sift tag has no wiki summary.
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Keypoint position and scale in SIFT
If I understood it right, a keypoint is a tuple $$(x,y,\sigma, r),$$ where $x,y$ define the position of the keypoint and $r$ an orientation (given by the most domiant gradiant vector around the ...
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Affine detector + SIFT descriptor
I am approaching to the Oxford Buildings dataset which contains already computed SIFT descriptors from affine detected keypoint locations.
Usually SIFT detector provides to its detected keypoints ...
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Detecting a filled glass object
I've been sent here from this question in stackoverflow, please excuse me if the question comes too specific and it's not in the manners in here:)
The task is to find a glass with specific liquid in ...
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How to proceed for BOW creation From sift features
I extracted sift feature to construct a bag-of-words model. I did the following to extract the feature vector:
Extracted features from the key frames.
After the feature extraction I tried using ...
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0answers
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Geometric models to discard image features
I am working on the implementation of a location recognition pipeline as detailed in the section 5.4 of the paper Leveraging 3D City Models for Rotation Invariant Place-of-Interest Recognition:
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1answer
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Object-Recognition using SIFT: Switching the order of images creates two different results
I've developed a large test-system which can use every interest-point-detector and -descriptor. I use it for evaluation of the given algorithms with the standford-image-collection of cd-covers. This ...
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1answer
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Image classification using SIFT features and SVM
I am hoping someone can explain how to use the bag of words model to perform image classification using SIFT/SURF/ORB features and a support vector machine?
At the moment I can compute the SIFT ...
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3answers
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Scale and Rotation invariant feature descriptors
Can you list some scale and rotational invariant feature descriptors for use in feature detection.
The application is for the detection of cars and humans in video captured by a UAV, using a ...
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1answer
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What scale should a detected SIFT point be extracted at?
I've heard this from a few different researchers but I can't find a definitive value. Given the "scale" extracted by David Lowe's SIFT detector, we need to extract a descriptor at a specific scale.
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Is sift a good way to extract features from an image?
I am trying to extract features from an image, but I have failed to get the points that I want to extract, and hence my image fails to match with the template.
Are there any checkpoints that I have ...
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3answers
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What are some free alternatives to SIFT/ SURF that can be used in commercial applications?
As far as I understand, both SURF and SIFT are patent protected.
Are there any alternative methods that can be used in a commercial application freely?
For more info on the patent check out:
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