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2019-10-01 15:33:52 -0500 commented question Best pattern/method for low resolution marker detection

Relying on color: You can probably differentiate 15 markers based on color, but significantly more than 15 will be chal

2019-10-01 15:08:00 -0500 commented question Methods for deciding if there is an object on the surface or not

Look into background modeling. There has been a lot of work on this subject. A "quick and dirty" approach would be to

2019-09-18 12:09:00 -0500 commented question OpenCV fisheye calibration error

I would also add that it is much easier to get calibration points into the far corners of the image if you use the Charu

2019-09-18 12:07:24 -0500 commented question OpenCV fisheye calibration error

I have done testing with the fisheye calibration vs standard calibration, and I found that the normal calibrateCamera fu

2019-09-18 12:06:43 -0500 commented question OpenCV fisheye calibration error

I have done testing with the fisheye calibration vs standard calibration, and I found that the normal calibrateCamera fu

2019-09-12 16:59:58 -0500 commented question Distance between Camera and Marker (calculate with Tvec)

My first guess would be that the intrinsic calibration is not very accurate (focal length in particular). How many imag

2019-09-12 11:57:48 -0500 commented question OpenCV fisheye calibration fails

One more thing is that with high distortion you might run into issues where the calibration either doesn't detect the co

2019-09-12 11:56:48 -0500 commented question OpenCV fisheye calibration fails

One more thing is that with high distortion you might run into issues where the calibration either doesn't detect the co

2019-09-12 11:40:48 -0500 commented question OpenCV fisheye calibration fails

A few ideas: If your calibration target and camera can be held in a fixed position, take multiple images and compute an

2019-09-12 11:35:28 -0500 commented question Distance between Camera and Marker (calculate with Tvec)

I can't tell from your notation what you are doing, but if you multiplying the two vectors component by component, I don

2019-09-12 11:23:53 -0500 commented question Determine the rotation, translation and scaling in homography matrix from estimateAffinePartial2D; Can I force no scaling? (Euclidan/Rigid)

I'm not sure what the differences are between estimateAffinePartial2D and estimateRigidTransform, but I use the former (

2019-09-12 11:23:06 -0500 commented question Determine the rotation, translation and scaling in homography matrix from estimateAffinePartial2D; Can I force no scaling? (Euclidan/Rigid)

I'm not sure what the differences are between estimateAffinePartial2D and estimateRigidTransform, but I use the former (

2019-09-12 11:14:07 -0500 commented question fixed points in findHomography

Add an Aruco marker somewhere, and use that to determine orientation, or use a Charuco claibration target (instead of th

2019-09-11 15:45:54 -0500 commented question why fx focal length is changing when I calibrating the camera.

In my experience the focal length shouldn't change by that much from one calibration to the next (unless you are changin

2019-09-11 15:39:29 -0500 commented question Multi camera calibration with flat pattern, error minimization.

For the 3 camera case you may want to look into using the trifocal tensor instead of two stereo calibrations. I'm not a

2019-09-11 14:51:18 -0500 commented question Wrong Intrinsic and Distrotion coefficients

What looks wrong to you about the image? If it is the curved black boundary, that is normal because when you undistor

2019-09-11 14:39:53 -0500 commented question OpenCV projectionPoints giving abnormal results

The intrinsic reprojection error is high, and the error from SolvePNP is absurdly high. I'd start by trying to address

2019-09-11 13:37:51 -0500 commented question OpenCV fisheye calibration fails

I have had problems with the fisheye calibration with OpenCV 3.2. As I recall my issue was that it would run "successfu

2019-04-03 10:58:39 -0500 commented question implementation calibration (zhang) homography problem

I haven't had a chance to look at the code yet, but I did examine the image more closely. One thing that I noticed is t

2019-04-02 15:08:00 -0500 commented question implementation calibration (zhang) homography problem

Post your code.

2019-03-28 17:34:47 -0500 commented question Converting from RGB => YUV => YUYV => RGB results in different image

YUYV format encodes two pixels in 4 bytes. The same 2 pixels as RGB use 6 bytes, so information is lost converting to YU

2019-03-28 17:34:12 -0500 commented question Converting from RGB => YUV => YUYV => RGB results in different image

YUYV format encodes two pixels in 4 bytes. The same 2 pixels as RGB use 6 bytes, so information is lost converting to YU

2019-03-21 13:06:37 -0500 commented answer Charuco calibration

@LBerger Have you had a chance to test with synthetic data? I'd be interested to know the results if you have any.

2019-03-17 21:33:06 -0500 commented answer Charuco calibration

How do you compare the intrinsics and extrinsics of the calibrated vs synthetic camera models? It is just by looking at

2019-03-17 10:11:06 -0500 commented question RGB changing B value affects R and G as well.... How to solve?

If you are saving the image as a JPG or other lossy format, you could be seeing compression artifacts that result in R a

2019-03-16 09:53:23 -0500 commented answer Charuco calibration

Using synthetic data with noise is a good idea. For this case I would add noise to synthetic input images (not image lo

2019-03-16 09:40:40 -0500 commented answer Charuco calibration

Using synthetic data with noise is a good idea. For this case I would add noise to synthetic input images (not image lo

2019-03-16 09:39:44 -0500 commented answer Charuco calibration

Using synthetic data with noise is a good idea. For this case I would add noise to synthetic input images (not image lo

2019-03-15 09:32:28 -0500 edited answer Charuco calibration

The aruco corners aren't nearly as accurate as the chessboard corners, particularly in OpenCV 3.3.1. The chessboard cor

2019-03-15 09:27:11 -0500 received badge  Editor (source)
2019-03-15 09:27:11 -0500 edited answer Charuco calibration

The aruco corners aren't nearly as accurate as the chessboard corners, particularly in OpenCV 3.3.1. The chessboard cor

2019-03-14 14:57:16 -0500 commented question Detection of holes

I prefer these methods to Hough transform: link text I was able to get repeatable and robust results, but my input im

2019-03-14 14:56:51 -0500 commented question Detection of holes

I prefer these methods to Hough transform: link text I was able to get repeatable and robust results, but my input im

2019-03-14 12:25:31 -0500 answered a question Charuco calibration

The aruco corners aren't nearly as accurate as the chessboard corners, particularly in OpenCV 3.3.1. The chessboard cor

2019-03-11 23:12:57 -0500 commented question Averaging of houghlines

I have dealt with this type of situation by doing something like: For all of the lines: angle = (angle + 45) mod 180

2019-03-11 13:59:37 -0500 commented question Averaging of houghlines

I have dealt with this type of situation by doing something like: For all of the lines: angle = (angle + 45) mod 180 co

2019-03-09 17:15:20 -0500 commented question i'm getting assertion failed error, while working on face recognition using opencv.

Yep...you are probably right...I totally missed the Anaconda part of the question...I was just focused on the assertion.

2019-03-09 17:14:15 -0500 commented question How do i get the angle of an object in front of my camera?

I'm not sure I understand what you are looking for, but maybe I do? First you need to figure out what your image center

2019-03-08 23:06:35 -0500 commented question How to detect fuzzy edge of a raindrop

What result are you looking for? An image with just the "fuzzy edge" pixels turned on, or a list of X,Y locations that

2019-03-08 22:57:20 -0500 commented question Detecting indentation on plate

How consistent is the surface quality, and how consistent is the lighting? I might be inclined to try to isolate the th

2019-03-08 22:38:44 -0500 commented question Detect rust using color segmentation

see: Color Constancy Here is a paper (I haven't read it) that classifies road scenes. Maybe this method could be appl

2019-03-08 22:38:09 -0500 commented question Detect rust using color segmentation

see: link text Here is a paper (I haven't read it) that classifies road scenes. Maybe this method could be applied to

2019-03-08 22:29:16 -0500 commented question Detect rust using color segmentation

Unless your rust is very consistent, and your lighting is also tightly controlled, it's probably going to be a good bit

2019-03-08 22:08:09 -0500 commented question i'm getting assertion failed error, while working on face recognition using opencv.

Whenever I get an OpenCV assertion that isn't obvious, I look at the source. See what is going on in matrix.cpp at 235

2019-03-07 13:40:13 -0500 commented question Camera Calibration for underwater lens

Admittedly I have no experience with underwater photography, so I don't have a good context for your specific issues, bu

2019-03-07 13:39:53 -0500 commented question Camera Calibration for underwater lens

Admittedly I have no experience with underwater photography, so I don't have a good context for your specific issues, bu

2019-03-07 13:39:15 -0500 commented question Camera Calibration for underwater lens

Admittedly I have no experience with underwater photography, so I don't have a good context for your specific issues, bu

2019-03-07 13:38:46 -0500 commented question Camera Calibration for underwater lens

Admittedly I have no experience with underwater photography, so I don't have a good context for your specific issues, bu

2019-03-07 13:31:45 -0500 commented question Camera Calibration for underwater lens

Admittedly I have no experience with underwater photography, so I don't have a good context for your specific issues, bu

2019-03-07 09:53:47 -0500 commented question Camera Calibration for underwater lens

You say it is not usable in air - what happens if you try to take pictures in air? If it is possible, I would attempt t