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2020-09-27 09:11:36 -0600 answered a question How to color the pixels in an image depending on whether they are inside/outside a zone/circle?

Use contour finding and bounding rect to get the rectangle of the collection of white pixels. Loop through all pixels in

2020-01-16 08:48:33 -0600 commented question [OpenCV.js] Template matching with mask

I wonder if the issue could be related to what is being masked. According to the docs, https://docs.opencv.org/4.2.0/df/

2020-01-15 06:38:42 -0600 answered a question How to draw contour lines between every colour?

You could use OpenCV's inrange function that will threshold based on color channel ranges. https://docs.opencv.org/3.4/d

2019-10-18 08:29:39 -0600 answered a question Feature extraction 3D

Not sure OpenCV has feature detectors or descriptors for your 3d adjacency data. Have you looked at 3d descriptors like

2019-10-01 14:33:36 -0600 answered a question efficiently fill cv::Mat

Here is my version of your functions and test code. I get very similar results for the Mat and vector reading using fst

2019-09-30 05:25:53 -0600 commented question android : Blur detection using OpenCV

Maybe this will help. https://www.pyimagesearch.com/2015/09/07/blur-detection-with-opencv/

2019-09-30 05:25:53 -0600 received badge  Commentator (source)
2019-09-17 15:18:57 -0600 answered a question Software synthesizer interface detection (lines inside of circles)

OpenCV has a couple techniques you can try and there is another that I don't think is in OpenCV. warp polar I cropped

2019-08-26 05:31:59 -0600 commented question Does exists a list of compatibles cameras with OpenCV

I have the same question. Before I buy a new camera, I would like to know if it will work with OpenCV.

2019-08-14 09:02:12 -0600 commented question HoughCircles detecting arches.

We have found hough circles to be unreliable and sensitive to its input parameters. Our preferred method is to use OpenC

2019-07-25 09:57:19 -0600 answered a question find outlined text in an image and cut the outline text ; with python

Would something like the following work? Here are the steps for the images below. convert the image to mono with cvtC

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2019-07-24 11:02:39 -0600 commented question Read image to an already allocated Mat

Interesting question. It doesn't look like there is a way to do this in the current code. It looks like imread_ calls m

2019-07-10 08:50:36 -0600 commented question Find hinge point or axis of rotation point?

Can you share some real images with us? Will the camera and object be fixed other than the rotation at the hinge? Will

2019-07-09 09:52:53 -0600 commented question How to take inputs from keyboard to start and stop the process?

Sounds like this may not really be an OpenCV question. Does opencv even have any keyboard input features? Stack Overflow

2019-06-30 15:07:32 -0600 commented answer How can I get the values of the pixels that are inside a contour?

It is a program I've been working on that allows you to test various computer vision algorithms and parameters. I plan t

2019-06-29 10:41:06 -0600 commented question How to create a image matrix of pixels showing there value

Set an roi (21x21) around the mouse position in the source image. Decide on a wd & ht value for each pixel in the ma

2019-06-29 10:33:22 -0600 commented question How can I export each image match using a template in opencv?

The code doesn't seem to match the question

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2019-06-29 10:21:45 -0600 answered a question How can I get the values of the pixels that are inside a contour?

Use a mask. Get the user selection as a contour then draw it as filled in a separate blank image. The 2nd image from the

2019-06-23 14:55:25 -0600 commented question How can correct a problem color

I am not quite sure what you mean by " put the correct color in the ball and the limits. because they vary with luminosi

2019-06-23 08:48:59 -0600 commented question How can I use Hough Transforms to fit a Plane

In the past, we have used principal component analysis (PCA) for this. https://docs.opencv.org/4.0.0/d3/d8d/classcv_1_1

2019-06-23 08:44:13 -0600 commented question Image classification in video stream with contours

Can you share some original images that have not been Canny filtered? I would like to see why template matching would no

2019-06-23 08:42:29 -0600 commented answer Measure similarity between two images with the same size

If you give matchTemplate two images that are the same size, it will return a single value or score. This score will be

2019-06-22 08:51:13 -0600 answered a question Measure similarity between two images with the same size

When I use template matching with TM_CCOEFF_NORMED, I get 0.83 score for Image1 & Image2 and 0.37 score for Image

2019-06-21 10:46:24 -0600 answered a question Object orientation (horizontal/vertical)

OpenCV has a useful tool called PCA (principal component analysis) https://robospace.wordpress.com/2013/10/09/object-ori

2019-06-18 07:02:56 -0600 answered a question Detection of red rectangle and environment lighting

Below are four images. The first is the red channel extracted from the original image. The 2nd is this extracted image t

2019-06-16 10:50:02 -0600 answered a question Compare font from image

Here's one solution. Do a binary inverse threshold so the letters are white and background is dark. Use findContours fun

2019-06-12 10:46:09 -0600 commented question Object orientation (horizontal/vertical)

Yes, orientation is a common problem in computer vision. Can you share some images with us?

2019-06-12 10:43:25 -0600 commented question Image classification in video stream with contours

You may want to look at template matching https://docs.opencv.org/4.0.0/df/dfb/group__imgproc__object.html#ga586ebfb0a7

2019-06-07 15:07:57 -0600 answered a question Remove the black line surrounding text in opencv

OpenCV's contours will work if you filter the contours by aspect ratio. In the image below the 2nd from the left is thre

2019-06-04 08:20:26 -0600 commented question Camera for Gear Inspection

Also, don't underestimate the need for a high quality lens for this fine resolution work. We recently worked on a projec

2019-06-04 08:12:55 -0600 answered a question Horizontal projection of area between 2 circles

One Opencv tool you should try is lineIterator. Create some radial lines and step across the boundary of the bottle ope

2019-06-02 07:36:25 -0600 answered a question robust external contour detection?

For more robust circle/ellipse finding, I like to use the line iterator. Set up radial lines either from the center of

2019-06-02 06:55:22 -0600 commented question Camera for Gear Inspection

I recommend you contact and talk to these guys: http://www.physimetrics.com/

2019-05-31 15:52:38 -0600 commented question Ignore part of an image whilst detecting LED colour

It would be helpful if you could share some images with us.

2019-05-31 07:36:59 -0600 commented answer Extract and detect line

No, these results came from another, larger c++ program

2019-05-25 07:26:19 -0600 answered a question i want to output coordinates.

Opencv has great tools for this problem. The 1st image from the left below is the blue channel extracted. The 2nd im

2019-05-25 06:58:41 -0600 commented question paper edge detection and perspective transform

Often machine vision challenges are not so much software as what I call staging. By staging I mean foreground, backgroun

2019-05-24 14:18:00 -0600 commented question How to get stats from image segmented with watershed?

After finding all the contours, if you take each one alone and dilate it with the same kernel, you should get a boundary

2019-05-18 07:34:35 -0600 commented answer Detect green laser dot

The morphology looks something like: Size kernelSize(3, 3); Mat kernel = getStructuringElement(MORPH_RECT, kernelSize);

2019-05-18 07:34:08 -0600 commented answer Detect green laser dot

The morphology looks something like: Size kernelSize(3, 3); Mat kernel = getStructuringElement(MORPH_RECT, kernelSize);

2019-05-18 07:33:53 -0600 commented answer Detect green laser dot

The morphology looks something like: Size kernelSize(3, 3); Mat kernel = getStructuringElement(MORPH_RECT, kernelSize);

2019-05-17 09:51:07 -0600 answered a question I am building and document scanner application and facing issue with detecting corner circles

I was able to get the image below with just a few OpenCV steps: threshold the image with binary_inverse and threshold

2019-05-17 08:58:17 -0600 edited answer color detection in different background of human machine interface

Here are the steps that seem to work well from left to right in the image below. original image apply Sobel filter wit

2019-05-16 14:37:26 -0600 commented question How to get stats from image segmented with watershed?

Would this help? I opened the above image as mono, did one iteration of erosion with 3x3 Rect kernel, did a threshold at

2019-05-16 14:36:19 -0600 commented question How to get stats from image segmented with watershed?

Would this help? I opened the above image as mono, did one iteration of erosion with 3x3 Rect kernel, did a threshold at

2019-05-15 05:29:55 -0600 commented question Finding subpixel position of fiducial shapes (Plus, Dot, Square)

Yes, please share some sample images with us. Hard to suggest anything without seeing what there is to work with.

2019-05-15 05:26:20 -0600 commented question What are the functions in opencv that takes only 8bit images

OpenCV works with many image types: single channel, multi channel, 8bit, 16bit, integral types and floating point types.

2019-05-15 05:17:35 -0600 commented answer Detect green laser dot

Hey Bhavesh, I am not sure what the original tank image looks like. Is the background unique somehow? If so, you can ta