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2021-02-02 09:27:57 -0600 received badge  Popular Question (source)
2019-10-15 07:16:33 -0600 commented question self intersected contour

Perhaps you can work with cv::isContourConvex() though the function output is undefined for intersected contours.

2019-04-29 05:43:45 -0600 commented question Ellipse detection in noisy images

For these kind of problems I often used CLAHE (see also: https://answers.opencv.org/question/211398/detecting-very-light

2019-04-29 05:42:33 -0600 received badge  Commentator
2019-04-29 05:42:33 -0600 commented question Ellipse detection in noisy images

For these kind of problems I often used CLAHE (see also: https://answers.opencv.org/question/211398/detecting-very-light

2019-04-11 07:35:17 -0600 commented question Detecting Very light particles in an image

I updated my answer. I think it is possible to get even better results when refining the parameters of CLAHE and the thr

2019-04-11 07:34:11 -0600 commented question Detecting Very light particles in an image

I updated my answer. I think it is possible to get even better results when refining the parameters of CLAHE and the thr

2019-04-11 07:33:38 -0600 edited answer Detecting Very light particles in an image

Hi, for me it works with a simple threshold + CLAHE: int main(int argc, char** argv) { cv::Mat img = cv::imread("

2019-04-11 03:48:51 -0600 commented answer Detecting Very light particles in an image

Oh sorry - my bad. I didn't read quite well :D. I will try something later. Seems to be more difficult.

2019-04-11 02:02:42 -0600 commented question Split number touching each other with openCV

Please show us what you have tried so far.

2019-04-11 02:01:15 -0600 answered a question Detecting Very light particles in an image

Hi, for me it works with a simple threshold: int main(int argc, char** argv) { cv::Mat img = cv::imread("img_test

2019-03-19 07:33:41 -0600 commented question How to get 4 image points(extreme points along diagonal) from circular contour?

Can you post an image for better understanding?

2019-02-27 02:27:01 -0600 commented question How to store points cordinats

Ok, my bad. So the actual problem is finding the start and end point of the fitted line? If so, you could use findContou

2019-02-26 07:59:17 -0600 commented question How to store points cordinats

Ok, you found your line as a ´cv::Vec4f´ where you have a starting point (x0, y0) and a vector collinear to the line (vx

2019-02-26 04:16:46 -0600 commented question How to store points cordinats

That should work. What is your problem now?

2019-02-14 02:45:05 -0600 commented question Help in understanding the theory to select optimum fringe frequency in three phase fringe structured light

Ok, I read the script again :D. I think you are right. The problem is that you have to be able to distinguish your proje

2019-02-11 06:16:08 -0600 commented question Help in understanding the theory to select optimum fringe frequency in three phase fringe structured light

We have a structured light system with three different camera pairs in our lab and if we want to gain a higher accuracy

2019-02-06 02:15:16 -0600 commented question Blurred background replacement

What happens if you convert your rgb image to grayscale values?

2019-02-06 02:11:54 -0600 commented question I want to use 1D guided filter?

When you look at line 160-164 in: https://github.com/opencv/opencv_contrib/blob/master/modules/ximgproc/src/guided_filte

2019-02-05 07:09:46 -0600 commented question I want to use 1D guided filter?

Could you be more specific? Are you referring to this: https://docs.opencv.org/3.4/de/d73/classcv_1_1ximgproc_1_1GuidedF

2019-02-04 06:12:25 -0600 commented question Correctly interpreting the Pose (Rotation and Translation) after 'recoverPose' from Essential matrix

@Eduardo: Different question concerning that topic. Is it necessary to normalize your image point coordinates as stated

2019-02-04 06:12:19 -0600 commented question Correctly interpreting the Pose (Rotation and Translation) after 'recoverPose' from Essential matrix

@Eduard: Different question concerning that topic. Is it necessary to normalize your image point coordinates as stated i

2019-01-30 02:30:43 -0600 commented question How is the principal point defined?

Since the calibration matrix or camera matrix can be defined using floating point coordinates I assume the principal poi

2019-01-29 06:27:50 -0600 commented answer Easiest way to overload OpenCV function

Is it possible that I only recompile the calib3d.hpp and the five-point.cpp using OpenCV 3.2.0 under OS Windows 10? How

2019-01-29 02:37:10 -0600 marked best answer Easiest way to overload OpenCV function

Hi,

what is the easiest way to overload an OpenCV function on my computer?
I want to use the function cv::findEssentialMat with two different camera matrices. At the moment this is not implemented in the standard five-point.cpp .(https://github.com/opencv/opencv/blob/master/modules/calib3d/src/five-point.cpp). Nevertheless it would be very easy to overload the function using two different camera models. I do not come from a programming background so would it be possible if I just add an overloaded function with additional camera matrices to the data file five-point.cpp in my build directory on my pc?
Or can I send a request to someone to implement it? Only around 5 lines of code would have to be changed. For me it seems it would be a lot of work if I code the complete five-point algorithm in combination with RANSAC myself.

2019-01-28 07:16:20 -0600 commented question locating template image using sift algorithm

When calling SIFT_create() you can add an argument nfeatures to retain a certain number of best features e.g. SIFT_creat

2019-01-28 07:16:07 -0600 commented question locating template image using sift algorithm

When calling SIFT_create() you can add an argument nfeatures to retain a certain number of best features e.g. SIFT_creat

2019-01-28 07:14:32 -0600 commented question locating template image using sift algorithm

When calling SIFT_create() you can add an argument nfeatures to retain a certain number of best features e.g. `SIFT_crea

2019-01-28 07:05:09 -0600 asked a question Easiest way to overload OpenCV function

Easiest way to overload OpenCV function Hi, what is the easiest way to overload an OpenCV function on my computer? I w

2018-12-06 05:44:54 -0600 edited answer Guidance on landscape image recognition

Hi, I am usually working with historical images and thus having the same problems. For your problem I would try/consider

2018-12-06 05:34:09 -0600 answered a question Guidance on landscape image recognition

Hi, I am usually working with historical images and thus having the same problems. For your problem I would try/consider

2018-11-27 02:50:42 -0600 commented question Wrong rank in Fundamental Matrix

Can you show one example of a Fundamentalmatrix and how do you determine the rank?

2018-11-12 07:09:10 -0600 commented question Pattern recognition with location feedback of missing patterns

You really want an answer but I won't do the complete job for you ;). I think a lot of different strategies can lead to

2018-11-12 04:43:33 -0600 commented question Pattern recognition with location feedback of missing patterns

I think the question is still too general. An image would be really nice here. Just some ideas here because it is not ve

2018-11-12 03:51:02 -0600 commented question Pattern recognition with location feedback of missing patterns

Just FYI - Here is a crosspost: [SO] (https://stackoverflow.com/questions/53252242/opencv-pattern-recognition-with-locat

2018-11-07 06:09:28 -0600 commented question ORB feature matching in pyramid

Since the octaves (=levels of the pyramid) are saved in the KeyPoint structure of OpenCV matches can be correctly drawn

2018-11-02 03:51:47 -0600 commented question Canny Edge shows a clear rectangle, how do I make that ROI?

I once had a similar problem and solved it with at first using morphological operations. Since you only have these singl

2018-09-26 06:01:43 -0600 commented question Parameters of cv::SVDecomp

Ok, I am dumb. I assumed my matrix is 27 x 18 because I got it from src.size(). In fact the matrix is 18 x 27 which I co

2018-09-26 06:00:11 -0600 marked best answer Parameters of cv::SVDecomp

Hi,

what are the parameters w, u, vt of cv::SVDecomp(src, w, u, vt) in comparison to Matlab's

[U,S,V] = svd(src);

I need the submatrices for further calculations that I already have given in Matlab. Can I directly translate w to U, u to S and vt to V. It seems like they are having varying Matrix sizes. I did not find further explanations on the SVDecomp function (e.g. here: documentation)

Edit:
I tried more stuff. I have the src matrix of size 27x18 (edited): In Matlab I get as result for the sizes U(27x27), S(27x18), V(18x18) which solves the SVD equation src=USV'

In OpenCV I open the same matrix src(27x18) and I get as result with cv::SVD::FULL_UV:
w(1x18), u(18x18), vt(27x27) which does not solve the equation. I am quite confused right now, what is going on in openCV SVD.

2018-09-26 06:00:10 -0600 commented question Parameters of cv::SVDecomp

Ok, I am dumb. I assumed my matrix is 27 x 18 because I got it from src.size(). In fact the matrix is 18 x 27 which I co

2018-09-26 05:38:09 -0600 commented question Parameters of cv::SVDecomp

Sry, had an error in the description. My source matrix is 27x18. Ok, you are even faster than me :D. Wait, I will try in

2018-09-26 05:35:33 -0600 commented question Parameters of cv::SVDecomp

Sry, had an error in the description. My source matrix is 27x18.

2018-09-26 05:32:05 -0600 edited question Parameters of cv::SVDecomp

Parameters of cv::SVDecomp Hi, what are the parameters w, u, vt of cv::SVDecomp(src, w, u, vt) in comparison to Matlab'

2018-09-26 05:22:41 -0600 edited question Parameters of cv::SVDecomp

Parameters of cv::SVDecomp Hi, what are the parameters w, u, vt of cv::SVDecomp(src, w, u, vt) in comparison to Matlab'

2018-09-26 03:59:34 -0600 edited question Parameters of cv::SVDecomp

Parameters of cv::SVDecomp Hi, what are the parameters w, u, vt of cv::SVDecomp(src, w, u, vt) in comparison to Matlab'

2018-09-25 07:36:08 -0600 asked a question Parameters of cv::SVDecomp

Parameters of cv::SVDecomp Hi, what are the parameters w, u, vt of cv::SVDecomp(src, w, u, vt) in comparison to Matlab'

2018-09-24 03:58:01 -0600 commented question For some reason - matrix multiplication crashes

I am doing some matrix calculations with the openCV Mat. Though, it is not the best to do it with. Can you try this for

2018-09-13 05:38:01 -0600 commented question How to extract RANSAC's inlier object points from the matrix produced by solvePNPRansac() or findHomography()?

See: http://answers.opencv.org/question/38194/understanding-findhomography-mask/ When I tried it with cv::findFundamenta