Form1.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

using Emgu;
using Emgu.CV;
using Emgu.CV.Util;
using Emgu.CV.Structure;
using Emgu.Util;
using Emgu.CV.CvEnum;
using Emgu.CV.UI;

using DirectShowLib;

namespace Web_camera
{
    public partial class Form1 : Form
    {
        private VideoCapture capture = null;
        private DsDevice[] webCams = null;
        private int selevtedCameraid = 0;
        public Form1()
        {
            InitializeComponent();
            

        }

        private void Form1_Load(object sender, EventArgs e)
        {
            webCams = DsDevice.GetDevicesOfCat(FilterCategory.VideoInputDevice);
            for(int i=0; i<webCams.Length;i++)
            {
                toolStripTextBox1.Items.Add(webCams[i].Name);
            }
        }

        private void toolStripTextBox1_SelectedIndexChanged(object sender, EventArgs e)
        {
            selevtedCameraid = toolStripTextBox1.SelectedIndex;
        }

        private void toolStripButton1_Click(object sender, EventArgs e)
        {
            try
            {
                if(webCams.Length ==0)
                {
                    throw new Exception("Нет доступных камер!");
                }
                else if(toolStripTextBox1.SelectedItem ==null)
                {
                    throw new Exception("Необходимо выбрать камеру!");
                }
                else if(capture !=null)
                {
                    capture.Start();
                }
                else
                {
                    capture = new VideoCapture(selevtedCameraid);
                    capture.ImageGrabbed += Capture_ImageGrabbed;
                    capture.Start();
                }
            }
            catch(Exception ex)
            {
                MessageBox.Show(ex.Message, "Ошибка!", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
        }

        private void Capture_ImageGrabbed(object sender, EventArgs e)
        {
            try
            {
                Mat m = new Mat();
                capture.Retrieve(m);
                pictureBox1.Image = m.ToImage<Bgr, byte>().Flip(Emgu.CV.CvEnum.FlipType.Horizontal).AsBitmap<Bgr,byte>();
                
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message, "Ошибка!", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
        }

        
        private void toolStripButton2_Click(object sender, EventArgs e)
        {
            try
            {
                if (capture != null)
                    capture.Pause();
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message, "Ошибка!", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
        }

        private void toolStripButton3_Click(object sender, EventArgs e)
        {
            try
            {
                if (capture != null)
                {
                    capture.Pause();
                    capture.Dispose();
                    capture = null;
                    pictureBox1.Image.Dispose();
                    pictureBox1.Image = null;
                    selevtedCameraid = 0;
                }

            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message, "Ошибка!", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
        }

        private void toolStripButton4_Click(object sender, EventArgs e)
        {
            if(capture ==null)
            {
                MessageBox.Show("Запустите камеру!");
                return;
            }
            try
            {
                Mat m = new Mat();
                capture.Retrieve(m);
                MakeScreen makeScreenForm = new MakeScreen(m.ToImage<Bgr, byte>().Flip(Emgu.CV.CvEnum.FlipType.Horizontal));
                makeScreenForm.ShowDialog();
            }
            catch(Exception ex)
            {
                MessageBox.Show(ex.Message, "Ошибка!", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
        }

        private void toolStripButton5_Click(object sender, EventArgs e)
        {
            Form3 Form3 = new Form3();
            Form3.ShowDialog();
        }
    }
}