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2016-03-30 03:28:24 -0500 commented answer How can I get frames from my webcam ?

If you want to get access to video camera, just use index of camera (0-based) instead of filename. Unfortunately I know nothing about CCS, you can try to use new headers:

#include "opencv2/opencv.hpp"
2016-03-28 01:49:26 -0500 commented answer How can I get frames from my webcam ?

Something like this:

#include "cv.h"
#include "highgui.h"
int main(int argc, char** argv)
CvCapture* capture=0;
IplImage* frame=0;
capture = cvCaptureFromAVI("C:\\video.avi"); 
if( !capture )
    throw "Error when reading steam_avi";

cvNamedWindow( "w", 1);

for( ; ; )
    frame = cvQueryFrame( capture );
    cvShowImage("w", frame);
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2015-12-22 01:38:17 -0500 commented answer NO QUESTION - Suggestions concerning this question & answer area

Hello guys! Thanks for the report. Firstly we are working on the next update of the site. We want to add new captcha method, because we have to spent a lot of time to stop spam now. After this update (it will be at the beginning of January) we start to work on tags.

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2015-11-12 17:03:04 -0500 answered a question Contact site admin for account issue

Password restoring should work now.

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2015-07-11 10:35:47 -0500 marked best answer I have a patch for OpenCV, how can I do a contribution?

Hello, I have a patch for OpenCV, and I want to contribute it. It is possible and is there any coding guidelines for OpenCV project?

2015-07-11 10:16:04 -0500 marked best answer How can I get frames from my webcam ?

How can I do that in C++ and Python?

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2015-06-10 06:24:58 -0500 answered a question How can i make a .gif image using some images in opencv?

Unfortunately OpenCV doesn't support animated gif. You can try to use imagemagick to do it.

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2015-03-26 03:13:05 -0500 answered a question I am not able to change my profile picture/gravatar.

The picture that appears on the users profiles is called gravatar (which means globally recognized avatar).

Here is how it works: a cryptographic key (unbreakable code) is calculated from your email address. You upload your picture (or your favorite alter ego image) the website from where we later retreive your image using the key.

This way all the websites you trust can show your image next to your posts and your email address remains private.

Please personalize your account with an image - just register at (just please be sure to use the same email address that you used to register with us). Default image that looks like a kitchen tile is generated automatically.

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2015-02-06 08:08:18 -0500 answered a question How to make reusable code for multiplatform projects (iOS)

Firstly please don't use C interface in iOS environment. C++ environment is more convenient.

It is possible to use C interface. Please add more headers with _c appendix:

#include "opencv2/imgproc/types_c.h" 
#include "opencv2/imgproc/impgroc_c.h"

Recommended way is to use the following header:

#ifdef __cplusplus
#include <opencv2 opencv.hpp="">
2015-02-02 03:33:42 -0500 commented question New user, need some basic help
    Mat m1(h,w,CV_8UC3, data); // assumes bgr capture;
    // now, you probably do this in a callback function, 
    //  and your 'data' ptr will go out of scope,
    //  thus we need a 'deep copy':
    Mat m2 = m1.clone();
2015-02-02 03:03:29 -0500 commented answer Contact forum moderators or other users service?

I sent you email to the email address connected with your account.

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2015-01-30 07:36:38 -0500 answered a question Contact forum moderators or other users service?

If you find some issues connected with this website, please add them to

Non-moderators can't use private messages.

If you have any problems with your account let me know here.

2015-01-24 01:30:57 -0500 commented answer Questions regarding the "How to contribute a tutorial/code or a bugfix to OpenCV source code" guide

@AlexanderShishkov - could this guide be added to the contribute page?

2015-01-20 01:29:33 -0500 commented answer ddepth parameter of the Laplacian filter

Yes, it converts each channel to 8 bit.

2015-01-15 00:50:17 -0500 commented question How to implement RanSac Algorithm using OpenCV to remove outliers?

In what way points should be joined? What is the model for your task?

2015-01-15 00:49:39 -0500 edited question How to implement RanSac Algorithm using OpenCV to remove outliers?

For example, we have 6 points with x and y coordinates. Two of them are outliers. We want to join remaining points using RanSac. Thanks in advance.

2015-01-14 13:22:49 -0500 answered a question ddepth parameter of the Laplacian filter

Let imagine Laplacian filter 3x3 kernel: image description

Let consider pixel with the following neighborhood:

1   1    1 
1   255 1
1   1    1

After applying Laplacian filter pixel value should be equal -4*255 + 4 = -1016

If we continue use CV_8U type (unsigned char 0-255) we can't save this value. So we should change type to CV_16S (signed short int, –32,768 to 32,767)

2015-01-12 06:38:46 -0500 answered a question Should I use OpenMP or parallel_for_ for a simple for loop ?

E.g. iOS doesn't support OpenMP. parallel_for_ supports different frameworks for parallelisation (TBB, GCD, Concurrency, ...) So you code for parallelisation can be more cross platform than OpenMP.

2015-01-07 07:27:24 -0500 commented answer [ANNOUNCEMENT] Welcome back to the OpenCV Q&A forum 2.0!

I have created github project for the website. Please use github issues for this project if you have some problems with this website.

2015-01-02 14:51:23 -0500 edited question Disparity Map missing object?


I'm working on creating a disparity map from a stereo image pair using OpenCV. I'm trying to look at a 3D model of an F-15. The disparity map I'm generating is very noisey and seems to be ignoring the plane altogether (almost creating a shadow of the plane among the noise). Does anyone know what may be causing this?

I can generate clear disparity maps from other images (inclusing the provided example images).

My block-mathing code is: StereoSGBM(min_disparity=80, num_disp=96, sad_window_size=3, uniqueness=15, speckle_window_size=10, speckle_range=2, p1=1, p2-64, max_disparity=124, full_dp=False, settings=None)

depth_map right_image

Update: Thank you to those who responded! To overcome difficulties matching textureless regions, I added a camo pattern to the wings and adjusted the SGBM parameters as suggested in the comments. The resulting disparity map is still poor.

camo_depth_map camo_right_image

StereoSGBM(min_disparity=0, num_disp=96, sad_window_size=9, uniqueness=15, speckle_window_size=10, speckle_range=2, p1=1, p2=64, max_disparity=1, full_dp=False, settings=None)

Any assistance would be greatly appreciated. Thank you!

2015-01-02 03:58:56 -0500 edited question How can I change the location where OpenCV stores and access its images

I have toasted the directory in android and it is in data/data. I want to store and access the images in SD card.

2014-12-31 03:20:15 -0500 answered a question Offline refence manual for opencv 3
2014-12-30 04:44:41 -0500 commented question I need details of FAST Algorithm

I don't see described problems.