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

namespace Emgu_Cam
{
    public partial class MainWindow : Form
    {
        //  declaring global variables
        private Capture capture;            //takes images from camera as image frames
        private bool captureInProgress;     //checks if capture is executing

        public MainWindow()
        {
            InitializeComponent();
        }

        private void captureButton_Click(object sender, EventArgs e)
        {
            CaptureImage();
            captureButton.Enabled = false;
            stopCaptureButton.Enabled = true;
        }



        private void ProcessFrame(object sender, EventArgs arg)
        {
            //we start from taking a frame from the camera
            Image<Bgr, Byte> ImageFrame = capture.QueryFrame();

            //now we must scale the image
            double scale;
            if((camImageBox.Width / (double)ImageFrame.Width) >= (camImageBox.Height / (double)ImageFrame.Height))
            {
                scale = camImageBox.Width / (double)ImageFrame.Width;
            }
            else
            {
                scale = camImageBox.Height / (double)ImageFrame.Height;
            }

            ImageFrame = ImageFrame.Resize(scale, INTER.CV_INTER_LINEAR);

            //insert the image
            camImageBox.Image = ImageFrame;
        }
        private void CaptureImage()
        {
            #region if capture is not created, create it now
            if (capture == null)
            {
                try
                {
                    capture = new Capture();

                }
                catch (NullReferenceException excpt)
                {
                    MessageBox.Show(excpt.Message);
                }
            }
            #endregion

            if (capture != null)
            {
                if(captureInProgress == false)
                {
                    Application.Idle += ProcessFrame;
                    captureInProgress = true;
                }
                else
                {
                    Application.Idle -= ProcessFrame;
                    captureInProgress = false;
                }

            }
        }

        private void stopCaptureButton_Click(object sender, EventArgs e)
        {
            CaptureImage();
            captureButton.Enabled = true;
            stopCaptureButton.Enabled = false;
        }

    }
}