How to get list of webcams?

[Andy]

I have two webcams installed on my system, but how to get the names of webcams installed on my system using emgucv?

At first when my app is started I will display the list of webcams, and then user will select which webcam he want to use!

[masangga]

hi,

maybe you can open this link

http://fewtutorials.bravesites.com/entries/emgu-cv-c/level-2---use-multiple-cameras-in-one-application

[Andy]

But how to get names of webcams installed?

[kerbooo]

Hi, you can use "DirectShowLib" dll http://sourceforge.net/projects/directshownet/files/DirectShowNET/v2.1/DirectShowLibV2-1.zip/download for listing system cams.

Usage example is below which i used in my project.

Code: Select all

....
//-> import DirectShowLib-2005.dll to your project referance
using DirectShowLib;
....


Code: Select all

....
//-> define var
private int _CameraIndex;
....

Put a ComboBox on your project form. Than rename that "ComboBoxCameraList"

Code: Select all

  //-> Create a List to store for ComboCameras
            List<KeyValuePair<int, string>> ListCamerasData = new List<KeyValuePair<int, string>>();

            //-> Find systems cameras with DirectShow.Net dll
            DsDevice[] _SystemCamereas = DsDevice.GetDevicesOfCat(FilterCategory.VideoInputDevice);

            int _DeviceIndex = 0;
            foreach (DirectShowLib.DsDevice _Camera in _SystemCamereas)
            {
                ListCamerasData.Add(new KeyValuePair<int, string>(_DeviceIndex, _Camera.Name));
                _DeviceIndex++;
            }

            //-> clear the combobox
            ComboBoxCameraList.DataSource = null;
            ComboBoxCameraList.Items.Clear();

            //-> bind the combobox
            ComboBoxCameraList.DataSource = new BindingSource(ListCamerasData, null);
            ComboBoxCameraList.DisplayMember = "Value";
            ComboBoxCameraList.ValueMember = "Key";


i hope, this approach can help you.

[Andy]

Ok Now I have added the code in form load().
It shows list of camera installed.
But I want webcam to be selected on click of my ok button. How to do that?

[kerbooo]

You can do that with ComboBox's "SelectedIndexChanged' method like below.

Code: Select all

  private void ComboCameras_SelectedIndexChanged(object sender, EventArgs e)
        {
            //-> Get the selected item in the combobox
            KeyValuePair<int, string> SelectedItem = (KeyValuePair<int, string>)ComboBoxCameraList.SelectedItem;

            //-> Assign selected cam index to defined var
           _CameraIndex = SelectedItem.Key;
        }

If you don't want to do with ComboBox's "SelectedIndexChanged" method.
You can use a button's "_Click" method.

Code: Select all

 private void YourButton_Click(object sender, EventArgs e)
{
    //-> Get the selected item in the combobox
            KeyValuePair<int, string> SelectedItem = (KeyValuePair<int, string>)ComboBoxCameraList.SelectedItem;
  //-> Assign selected cam index to defined var
            _CameraIndex = SelectedItem.Key;
 }
       

After that, you can use "_CameraIndex" var with new capture object.

Code: Select all

_Capture = new Capture(_CameraIndex);

[Andy]

Thankyou Kerbooo

[kerbooo]

You're welcome

[olugbone]

I am trying to get a higher resolution from my webcams. I can only get a default of 640X480.

Here is my code:

Code: Select all

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using Emgu.CV;
using Emgu.CV.Structure;
using Emgu.Util;
namespace Camera_Capture
{
 public partial class Form1 : Form
 {
 //declaring global variables
 private Capture capture1,capture2; //takes images from camera as image frames
 private bool captureInProgress; // checks if capture is executing

 public Form1()
 {
 InitializeComponent();
 }
 private void Form1_Load(object sender, EventArgs e)
 {
 capture1 = new Capture(0);
 capture1.SetCaptureProperty(Emgu.CV.CvEnum.CAP_PROP.CV_CAP_PROP_FRAME_WIDTH, 1280);
 capture1.SetCaptureProperty(Emgu.CV.CvEnum.CAP_PROP.CV_CAP_PROP_FRAME_HEIGHT, 720);

 capture2 = new Capture(1);
 this.capture2.SetCaptureProperty(Emgu.CV.CvEnum.CAP_PROP.CV_CAP_PROP_FRAME_WIDTH, 1024);



 }

 private void button1_Click(object sender, EventArgs e)
 {
 #region if capture is not created, create it now
 if (capture1 == null)
 {
 try
 {
 capture1 = new Capture(0);
 capture2 = new Capture(1);
 }
 catch (NullReferenceException excpt)
 {
 MessageBox.Show(excpt.Message);
 }
 }
 #endregion

 if (capture1 != null)
 {
 if (captureInProgress)
 { //if camera is getting frames then stop the capture and set button Text
 // "Start" for resuming capture
 button1.Text = "Start!"; //
 Application.Idle -= ProcessFrame;
 }
 else
 {
 //if camera is NOT getting frames then start the capture and set button
 // Text to "Stop" for pausing capture
 button1.Text = "Stop";
 Application.Idle += ProcessFrame;
 }

 captureInProgress = !captureInProgress;
 }
 }
 private void ProcessFrame(object sender, EventArgs arg)
 {
 Image<Bgr, Byte> ImageFrame = capture1.QueryFrame();
 camimageBox.Image = ImageFrame; //line 2
 Image<Bgr, Byte> ImageFrame2 = capture2.QueryFrame();
 imageBox1.Image = ImageFrame2;
 }

 private void ReleaseData()
 {
 if (capture1 != null)
 capture1.Dispose();
 }
 }
}

Thanks in advance

[Andy]

How to change the webcam in runtime?

Means currently my application is running on webcam A, now I will select Webcam B. Immediately my application should switch to Webcam B.