feature-detection Questions

4

Solved

I am currently trying to black out everything outside a circle. I am drawing the circle using the following lines of code: cv::Point center(cvRound(circles[i][0]), cvRound(circles[i][1])); // CVRo...
Gossipy asked 27/8, 2013 at 7:59

1

Solved

Is there a way of storing a built-in javascript method in a variable to set different behaviour for when this method isn't available in certain browsers? My specific case is for intersectionObser...
Bullpup asked 14/2, 2018 at 18:5

5

Solved

I've written some code that uses OpenCV libraries to detect white lines painted on grass. I need someone's opinion on the approach I used (as I'm sure there's a much better way than mine). Also, th...

3

Solved

I want to limit a SurfFeatureDetector to a set of regions (mask). For a test I define only a single mask: Mat srcImage; //RGB source image Mat mask = Mat::zeros(srcImage.size(), srcImage.type()); ...
Pearliepearline asked 3/5, 2013 at 18:10

3

Solved

I have a short question: When I do feature-matching in OpenCV, what does the distance attribute mean of DMatches in MatOfMatches? I know that I have to filter matches with bigger distance because ...
Dryasdust asked 8/6, 2013 at 6:35

1

Solved

By reading a few answers on stackoverflow, I've learned this much so far: The mask has to be a numpy array (which has the same shape as the image) with data type CV_8UC1 and have values from 0 to ...
Rabelais asked 22/8, 2017 at 6:33

7

Solved

SURF is patented, as is SIFT. ORB and BRIEF are not patented, but their features are not scale-invariant, seriously limiting their usefulness in complex scenarios. Are there any feature extractors...

2

Solved

As far as I know, CNN rely on sliding window techniques and can only indicate if a certain pattern is present or not anywhere in given bounding boxes. Is that true? Can one achieve localization wi...

3

I have a training set of images, for each of which I've detected and computed their feature vectors (using ORB feature descriptors and extractors. The questions is: since I need to save those featu...
Solubilize asked 7/3, 2013 at 12:35

5

I am using HTML5 <input type="date" />, which works fine in Chrome and I get the calendar popup to select the date. But in firefox it acts like a text box and no calendar pops up. After d...
Fumy asked 28/5, 2015 at 9:56

1

Solved

I'm currently trying to work with a Brute Force feature matcher using SIFT in openCV, using python. I'm trying to utilise it for my image search function on my server, where I'm inputting an image ...

1

Solved

I have been trying to figure out whether it's possible to nest CSS feature queries (also known as “CSS @supports”) and regular media queries, and what would be the correct way to do it. Example A ...
Jodhpurs asked 24/2, 2017 at 11:55

4

Solved

I am trying to extract features using OpenCV's HoG API, however I can't seem to find the API that allow me to do that. What I am trying to do is to extract features using HoG from all my dataset (...

1

Solved

I am building a simple project in Python3, using OpenCV3, trying to match jigsaw pieces to the "finished" jigsaw image. I have started my tests by using SIFT. I can extract the contour of the jig...
Margo asked 20/2, 2017 at 14:8

1

Solved

I am studying something about some possibilities of OpenCV object detection and this is confusing to me. I just don't see the difference between these two.

4

Solved

As a self-development exercise, I want to develop a simple classification algorithm that, given a particular cell of a Dilbert cartoon, is able to identify which characters are present in the carto...

2

Solved

There are several kinds of detectors and descriptors, like SIFT, SURF, FAST. I wonder are they all eligible for real-time applications? Which is the best or better? And furthermore, is Harri...
Squib asked 26/8, 2013 at 6:25

1

I recently discovered phase correlation in OpenCV, which with the Log Polar Transform (LPT) can perform rotation and scale invariant template matching. I'm wondering what the difference is between ...
Mort asked 10/5, 2016 at 16:18

4

Solved

I am playing around with CSS-animated SVG elements and came across the problem that even though all technologies, which are used, are supported by some browsers the combination is not, i.e. CSS-ani...
Landowner asked 22/7, 2015 at 15:47

2

Solved

Does anyone know the difference between feature detection and descriptor extraction in OpenCV 2.3? I understand that the latter is required for matching using DescriptorMatcher. If that's the cas...

2

Solved

As known in OpenCV 2.4.9.0 are these feature-detectors: SIFT, SURF, BRISK, FREAK, STAR, FAST, ORB. http://docs.opencv.org/modules/features2d/doc/feature_detection_and_description.html http://doc...

0

I am looking for a way to test if a browser can have an external svg reference in the use element: <svg> <use xlink:href="sprite.svg#icon-name"></use> </svg> This works ...
Kuvasz asked 17/8, 2016 at 2:1

1

I was trying to show the matched keypoints between two Images (one that is captured from my camera and the other from the database) Can anyone help me out in writing DrawMatches function in my cod...
Turley asked 5/8, 2016 at 11:17

0

I just used an open source implementation of an ORB. How can I implement ORB further by adding new modules? What can I do from my end in order to get better results than just using an ORB. Am th...
Inesinescapable asked 30/6, 2016 at 8:43

2

Solved

Is there any way to detect whether a browser supports CSS custom properties (eg. color: var(--primary))? I need to write a script that behaves slightly differently in browsers that don't sup...
Sojourn asked 24/6, 2016 at 11:9

© 2022 - 2024 — McMap. All rights reserved.