Live video feed from multiple webcam dynamically using opencv and c++

Question

0.00/5 (No votes)

See more:

I have implemented the code that displays four windows of opencv to get live video feed from 4 webcams. But the code is not dynamic. I want to make it dynamic where it will display only windows equal to the number of cameras attached to System. I am getting the number of camera attached to the machine. The only task remains is to implement the code for dynamic scenario.
Here's the code.

C++

#include<opencv\cv.h>
#include<opencv\highgui.h>
#include<d:\my>

using namespace cv;

int main(){

	//Create matrix to store image
	Mat image;
	Mat image1;
	Mat image2;
	Mat image3;

	//Mat image1;
	//initailize capture
	videoInput VI;
	int numDevices = VI.listDevices();	
 	VideoCapture cap;
	VideoCapture cap1;
	VideoCapture cap2;
	VideoCapture cap3;

	bool x = false;
	//VideoCapture cap1;
	cap.open(0);
	cap1.open(1);
	cap2.open(2);
	cap3.open(3);
	
	namedWindow("Camera 1",1);
	namedWindow("Camera 2",1);
	namedWindow("Camera 3",1);
	namedWindow("Camera 4",1);

	while(1){
		//copy webcam stream to image
		cap >> image;
		cap1 >> image1;
		cap2 >> image2;
		cap3 >> image3;
		cap4 >> image4;
		//cap1 >> image1;
		imshow("Camera 1",image);
		imshow("Camera 2",image1);
		imshow("Camera 3",image2);
		imshow("Camera 4",image3);

		//imshow("Camera 2",image1);
		//delay 33ms
		waitKey(33);
	}
}

Please point me to right direction for the making the dynamic code. Later i want to implement the code in mfc.

Posted 25-Oct-13 19:14pm

Mayur S7789

Updated 26-Oct-13 3:39am

André Kraak

v2

Add a Solution

Comments

Sergey Alexandrovich Kryukov 26-Oct-13 2:24am

Not clear where is your problem. You successfully got the number of cameras. So, what's missing?
—SA

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Jonathan Davies · Accepted Answer · 2013-10-26T03:29:00

There's likely to be a list of cameras provided, perhaps by the camera API - that's the first place to look, camera manufacturers usually provided example code. And perhaps linking to a list of structures, where each structure contains information about one camera. I'd look for these.
When using cameras (on a firewire bus) I needed be able to detect newly a added camera and reasoned that a person is there to add (or remove that camera) and so can press a button 'refresh camera list' rather demand an event fired by some low-level detection. Though it may be your API provides such an event so again, have a look for that.
You might later find it useful to write a C++ class to handle such additions and removals. I've added the header from such a class I wrote, and its description, to show how this might look.

C#

#include "CameraList.h" // The list of [camera] nodes on the bus that are managed.

/* The number of cameras on the firewire bus can change, that is a camera could be manually connected or disconnected or a connected camera could fail therefore we need to have our list of cameras updated, both on an event driven basis and at our request. A Bus Manager has been introduced to take care of this. Event driven changes are not really a problem, but at times the firewire bus has been initialised and generated events before the list of information on the ameras is actually required. So being able to ask the Bus Manager to regenerate the list upon demand, simply by calling the event handler OnNodeListChanged is extremely useful.
CBusManager also wraps the code for adding and removing nodes from the list of Cameras, making use of the bus simpler and cleaner. */

class CBusManager
{
public:
    CBusManager(CCameraList* pCameraList);
    void OnNodelistChanged();
    void EnableNode(UINT32 Ix,BOOL Enable);
    void RemoveNode(UINT32 Ix);
    void AddNode(FGNODEINFO *pInfo);

    CCameraList* m_pCameraList;
};