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Questions tagged [freak]

Fast Retina Keypoint is a keypoint descriptor based on human retina visual system.

A cascade of binary strings is computed by efficiently comparing image intensities over a retinal sampling pattern.

It is a competitive solution compared to other descriptors like SIFT or SURF.

Reference:

FREAK: Fast Retina Keypoint

Alexandre Alahi, Raphael Ortiz, Pierre Vandergheynst

Ecole Polytechnique Fed´ erale de Lausanne (EPFL), Switzerland

22 questions
18
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4 answers

Why does opencv FREAK extractor remove so many keypoints, specifically using ORB detector

I am using OpenCV 2.4.3 c++ interface to find matching points between two images. The first attempt was using SURF. The only problem is the consuming time, so I tried the new FREAK extractor. Using SURF for detection and FREAK for description, I…
min.yong.yoon
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2 answers

OpenCV FREAK: Fast Retina KeyPoint descriptor

I am developing an application which involves the use of Freak descriptors, just released in the OpenCV2.4.2 version. In the documentation only two functions appear: The class constructor A confusing method selectPairs() I want to use my own…
Jav_Rock
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15
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2 answers

FREAK Descriptor with Opencv Python

I was trying to implement the FREAK Descriptor in Python using Opencv. Here is the code i'm using: def surf_freak_detect(image,hessianThreshold): surfDetector = cv2.SURF(hessianThreshold) …
Colenso Castellino
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7
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2 answers

OpenCV FREAK returns too many outliers

I am trying the quite new descriptor FREAK from the latest version of OpenCV following the freak_demo.cpp example. Instead of using SURF I use FAST. My basic code is something like this: std::vector keypointsA, keypointsB; Mat…
Mar de Romos
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1 answer

BRISK and FREAK descriptors in MATLAB

I'm using MATLAB 2014a for extracting BRISK and FREAK descriptors. I couldn't find any option to reduce the bit string size to 128 or 256, they both generated as 512 bits. I think FREAK does not allow this by algorithm but BRISK should allow. Does…
guneykayim
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6
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2 answers

Convert a row of cv::Mat to an int

I have a matrix of descriptors from FREAK description extraction where each row is a descriptor of 64 elements. I need to create a vector from this matrix due to the system requirements. I tried this so far: Mat…
Jav_Rock
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4
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2 answers

opencv Freak - Can I use Freak feature descriptor with BOW?

I am trying to use Freak in opencv to detect features and extract descriptors, then build my BOW vocabulary and for each image use the vocabulary to match with BOW. You know, the whole thing. I know BOW can be used with other descriptors like SIFT…
coolC
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4
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1 answer

Cannot find FREAK detector in OpenCV

I am developing some code in OpenCV 2.4 and I want to test the FREAK detector but I get compilation errors. I am including the feature2d.h, what can I do to fix this?
Carlos Cachalote
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3
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0 answers

Cython access to opencv features2d module

I really need your help. I try to get access to the opencv descriptors AKAZE and FREAK with Python using Cython (until now I just tried it with FREAK). But everytime I try to compile it I get an error message about 730 lines because Cython says it…
Leo
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1 answer

Having a hard time finding any tutorials/examples for the FREAK feature extractor

I am trying to implement a feature/object tracking application using OpenCV and C++. Currently I am using the goodFeaturesToTrack function to create my feature vector from my first frame. From there, I am passing it to the calcOpticalFlowPyrLk…
szakeri
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3
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2 answers

OpenCV FREAK not robust to rotation/scaling

I have been dealing with OpenCV FREAK descriptor and after achieving quite awesome matching results with two similar oriented and scaled images I started trying with scaled and rotated images. FREAK is supposed to be invariant to scale/rotation, but…
Mar de Romos
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2
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0 answers

ORB Descriptors with any other detectors can be used?

Can I use ORB descriptor with any other detectors like AGAST / FREAK instead of ORB detector? Does it yield in much more efficient results.
WhoAmI
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2 answers

OpenCV : FREAK Descriptor arguments

I am having a difficulty in understanding the parameters orientationNormalized and scaleNormalized in the FREAK descriptor. Any idea on what they mean or do? OpenCV FREAK doc :…
user1403483
1
vote
1 answer

Assertion failed while drawing match Key Points BF BRISK+FREAK

I am trying to stitch two images using BRISK+FREAK Here's the code, When I try to draw the matches I get an error error: OpenCV(4.1.2) /io/opencv/modules/features2d/src/draw.cpp:225: error: (-215:Assertion failed) i1 >= 0 && i1 <…
Santhosh Dhaipule Chandrakanth
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Noclassdeffounderror DataBufferByte exception Freaking Math open source ios

I've got an open source game base on Libgdx at https://github.com/miniclassic/freakingmath that called Freaking Math Open Source. It's addictive,funny game and support mutilple plat form. It's ok on Android. But when i compile and run on device…
Tung Ha
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