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2018-09-15 08:34:22 -0600 commented answer Finding local maximum in grayscale image

I don't know exactly what you want. If you try to do a NonMaximumSupression try something like (For C++): cv::Mat imgMa

2018-09-15 08:32:53 -0600 commented answer Finding local maximum in grayscale image

I don't know exactly what you want. If you try to do a NonMaximumSupression try something like (For C++): cv::Mat imgMa

2018-09-13 12:43:42 -0600 edited answer Finding local maximum in grayscale image

dilate is a maximum filter. Just use it with the desired size and form (MORPH_RECT, MORPH_ELLIPSE, or a custom kernel).

2018-09-13 12:38:57 -0600 answered a question Finding local maximum in grayscale image

dilate is a maximum filter. Just use it with the desired size and form (MORPH_RECT, MORPH_ELLIPSE, or a custom kernel).

2018-08-29 11:56:54 -0600 commented question how to take points InputArray objectPoints, InputArray imagePoints could you please explain in detail with an example

Whats unclear? InputArray and OutputArray are just proxy arguments. You can pass for objectPoints and imagePoints either

2018-08-28 15:11:47 -0600 commented answer FindContours Duplicate Points

Imagine a straight line with one extra pixel on one side. How else should the algorithm detect this single pixel which d

2018-08-28 15:08:10 -0600 commented answer FindContours Duplicate Points

Imagine a straight line with one extra pixel on one side. How else should the algorithm detect this single pixel which d

2018-08-28 15:07:32 -0600 commented answer FindContours Duplicate Points

Imagine a straight line with one extra pixel on one side. How else should the algorithm detect this single pixel which d

2018-08-26 08:24:44 -0600 answered a question FindContours Duplicate Points

In case the contour is not closed (area is 0 or length of contour) you get duplicate contour points and this is the corr

2018-08-06 09:09:28 -0600 commented question How do I view numbers in a cv::mat when debugging in visual studio

What*s wrong with Image Watch 2017? To watch raw values you just have to zoom in enough. An alternative way would be to

2018-08-03 18:11:55 -0600 received badge  Nice Answer (source)
2018-08-03 12:41:49 -0600 commented answer How does OpenCV ensure that Mat::data is correctly aligned?

If you use Mat with void* your data alignment is unchanged. This is only a Mat wrapper around your data and does not cop

2018-08-02 10:26:17 -0600 answered a question How does OpenCV ensure that Mat::data is correctly aligned?

Take a look here and here

2018-04-16 13:07:31 -0600 answered a question To obtain Regular/Smooth Shape

If you deal with contours, take a look at approxPolyDP

2018-01-16 11:43:52 -0600 commented question Gpu is working slower than Cpu(General Filters)

How did you measure the performance? For valid results you should run your operation about a hundred times without usin

2017-12-16 17:51:25 -0600 answered a question template matching in source image containing multiple rotated images

Simple template matching is not rotation (and scale) invariant. Take a look at this project.

2017-12-10 14:54:16 -0600 commented question Add .dxf drawing to OpenCV Mat object

Also this could be interesting link text

2017-12-07 14:00:10 -0600 commented question LineSegmentDetector throws exception on resized image

I think I remember that a vector wasn't resized when the image is scaled down. So it's size was from calculation before

2017-12-05 11:59:07 -0600 commented question Optimization of Canny edge detector

Add some images and an example code. Also give us some information what system you use and than we can help you ;)

2017-11-28 11:54:01 -0600 answered a question how to accelerate filter2D with multi-core CPU?

If your convolution is separable you can use external parallelization like in my answer here. When using sepFilter2D you

2017-11-11 03:49:10 -0600 answered a question arcLength vs ContourArea?

Your contours are not closed. In this case the contour area is calculated as a line. By the way: the arc length of a 1p

2017-11-10 15:20:08 -0600 received badge  Nice Answer (source)
2017-11-10 09:51:18 -0600 edited answer parallel_for_ : nstripes parameter

It's the number of stripes you parallel loop is splitted. It is not the number of threads. Here is the implementation fo

2017-11-10 09:49:53 -0600 answered a question parallel_for_ : nstripes parameter

It's the number of stripes you parallel loop is splitted. It is not the number of threads. Here is the implementation fo

2017-11-10 06:12:39 -0600 commented question Smoothing binary mask and sort out distortion

Correction: You detect everything except the yellow square mask and the distortions. white: foreground black: backgrou

2017-11-06 11:29:34 -0600 commented answer parallel_for_

parallel_for_ is a wrapper not only for TBB. It also works with OpenMP, pthreads (Linux), Concurrency and WINRT (Windows

2017-11-05 11:44:39 -0600 commented answer Dilate and Erode

For Canny it is the best using the colour image because the algorithm uses the strongest gradient for each pixel out of

2017-11-05 09:38:34 -0600 commented answer Dilate and Erode

Processing a Sobel filter on a binarized image makes little sense. You can try to smooth the input image a little bit u

2017-11-05 06:10:56 -0600 answered a question Dilate and Erode

Dilate and erode are maximum-/minimum filters. So there is no correct or wrong approach. It simply depends on what you t

2017-10-22 10:40:20 -0600 commented answer Neon support for basic matrix operations

This code is currently a mixture of using SSE, Neon and the wrapper interface as well as using functors. I try to give y

2017-10-22 10:35:11 -0600 commented answer Neon support for basic matrix operations

This code is currently a mixture of using SSE, Neon and the wrapper interface as well as using functors. I try to give y

2017-10-22 09:09:52 -0600 edited answer Neon support for basic matrix operations

Neon seems to be supported (see here). Currently there are some pull requests like this which replaces explicit Neon and

2017-10-22 09:06:48 -0600 edited answer Neon support for basic matrix operations

Neon seems to be supported (see here). Currently there are some pull requests like this which replaces explicit Neon and

2017-10-22 08:59:51 -0600 answered a question Neon support for basic matrix operations

Currently there is a pull request which replaces explicit Neon and SSE operations with OpenCV's vector wrapper which sav

2017-10-20 11:35:27 -0600 received badge  Nice Answer (source)
2017-10-20 10:54:23 -0600 edited answer Where are the java source files?

OpenCV java uses C++ under the hood. There are no java source files for the algorithms itself, but java wrappers. You ca

2017-10-20 10:53:26 -0600 answered a question Where are the java source files?

OpenCV java uses C++ under the hood. There are no java source files for the algorithms itself, but java wrappers. You ca

2017-09-28 12:45:00 -0600 answered a question Contour to Spline

Take a look at approxPolyDP

2017-09-26 12:17:15 -0600 commented question Size of executable when static

On Windows I got ~7,5MB for a typical, small terminal application with static build until OpenCV 3.2. Since OpenCV 3.3 i

2017-09-26 12:07:14 -0600 answered a question How do you compute abs() using UMat?

Mmh, cv::abs doesn't seem to exist anymore. Even in docs the link is dead. As a workaround you could try: cv::absdiff(s

2017-09-25 14:41:22 -0600 commented answer Difference between a list of points and list of pixels.

You can use cv::arrowedLine in OpenCV 3.3 (and 3.2?). Round your points to int and pass it to the function.

2017-09-25 11:10:28 -0600 commented answer Difference between a list of points and list of pixels.

Yes it's about it's location. Here is a good explanation. If you are using OpenGL for example you can render in subpixe

2017-09-24 09:15:03 -0600 answered a question Difference between a list of points and list of pixels.

In general a list of pixels is a list with brightness values (grayvalues or in case of RGB 3 channels with brightness va

2017-09-23 10:22:05 -0600 commented answer iOS - Xcode - OpenCV - findContours error

Can you check CV_Assert(srcImage.type() == CV_8UC1); before findContours and are you sure cvtColor isn't throwing tha

2017-09-23 10:18:31 -0600 commented answer iOS - Xcode - OpenCV - findContours error

Can you check CV_Assert(srcImage.type() == CV_8UC1); before findContours and are you sure cvtColor isn't throwing tha

2017-09-23 09:07:14 -0600 answered a question iOS - Xcode - OpenCV - findContours error

Your srcImage type is not correct. Make sure it is single channel (which should be) and it's depth is CV_8U.

2017-09-21 13:18:38 -0600 commented answer Applying gaussian mask in frequency domain c++ opencv

The source code for mulSpectrums is here

2017-09-20 12:26:16 -0600 answered a question How to install openCV with contrib modules

I had never any bigger problems with building OpenCV with contrib modules, but I have to admit that the contrib master b