อยากทราบวิธีแก้ปัญหาดึงภาพมาจากกล้องแล้วรีโซลูชั่นไม่ตรงกันครับ Aforge.net c#.net

using System;
using System.Drawing;
using System.Collections.Generic;
using System.Linq;
using System.Collections.ObjectModel;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Input;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using Accord.Video.FFMPEG;
using AForge.Video;
using AForge.Video.DirectShow;
using GalaSoft.MvvmLight;
using GalaSoft.MvvmLight.CommandWpf;
using Microsoft.Win32;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using System.IO.Ports;
using Microsoft.Kinect;
using System.Configuration;
using System.IO;
using System.ComponentModel;
using System.Threading;




  private void MainWindow_Closing(object sender, System.ComponentModel.CancelEventArgs e)
        {
            
            StopCameraPtz();
            Dispose();
            Thread.Sleep(1000);
           
        }

        private void btnStart_Click(object sender, RoutedEventArgs e)
        {
            StartCameraPTz();
        }

        private void video_NewFrame(object sender, NewFrameEventArgs eventArgs)
        {
            try
            {
                if (_recording)
                {

                    if (_firstFrameTime != null)
                    {
                        _writer.WriteVideoFrame(eventArgs.Frame, DateTime.Now - _firstFrameTime.Value);
                       
                    }
                    else
                    {
                        _writer.WriteVideoFrame(eventArgs.Frame);
                        _firstFrameTime = DateTime.Now;
                        Console.WriteLine(_firstFrameTime.Value);

                    }//
                }
               
                using (var bitmap = (Bitmap)eventArgs.Frame.Clone())
                {
                    Console.WriteLine (bitmap.Size.Width);
                    Console.WriteLine(bitmap.Size.Height);
                    
                    bi = bitmap.ToBitmapImage();
                   
                    bitmap.Dispose();
                }
                Console.WriteLine(bi.Width+"x"+bi.Height);
                bi.Freeze(); // avoid cross thread operations and prevents leaks
                Dispatcher.BeginInvoke(new ThreadStart(delegate { ImagePtz.Source = bi; }));
            }
            catch (Exception exc)
            {
                MessageBox.Show("Error on _videoSource_NewFrame:\n" + exc.Message, "Error", MessageBoxButton.OK, MessageBoxImage.Error);
                StopCameraPtz();
            }
            Thread.Sleep(50);
        }

        private void btnStop_Click(object sender, RoutedEventArgs e)
        {
            StopCameraPtz();
        }
        private void btnStoprec_Click(object sender, RoutedEventArgs e)
        {
            _recording = false;
            _writer.Close();
            _writer.Dispose();
        }

        private void btnStartrec_Click(object sender, RoutedEventArgs e)
        {
            var dialog = new SaveFileDialog();
            dialog.FileName = "Video1";
            dialog.DefaultExt = ".mp4";
            dialog.AddExtension = true;
            var dialogresult = dialog.ShowDialog();
            if (dialogresult != true)
            {
                return;
            }
            _firstFrameTime = null;
            _writer = new VideoFileWriter();
            Console.WriteLine(bi.Format);
            _writer.Open(dialog.FileName, (int)Math.Round(bi.Width, 0), (int)Math.Round(bi.Height, 0), 30, VideoCodec.H264 );
            
            // _writer.Open(dialog.FileName,   1920 , 1080, 60, VideoCodec.H264, 100000);
            _recording = true;
        }

        private void btnSavesnp_Click(object sender, RoutedEventArgs e)
        {
            var dialog = new SaveFileDialog();
            dialog.FileName = "Snapshot1";
            dialog.DefaultExt = ".png";
            var dialogresult = dialog.ShowDialog();
            if (dialogresult != true)
            {
                return;
            }
            var encoder = new PngBitmapEncoder();
            encoder.Frames.Add(BitmapFrame.Create(bi));
            using (var filestream = new FileStream(dialog.FileName, FileMode.Create))
            {
                encoder.Save(filestream);
            }
        }

        public void Dispose()
        {
            if (_videoSource != null && _videoSource.IsRunning)
            {
                _videoSource.SignalToStop();
                _videoSource.WaitForStop();
                _videoSource = null;
            }
            _writer?.Dispose();
          
        }

        private void GetVideoDevices()
        {
            var devies = new FilterInfoCollection(FilterCategory.VideoInputDevice);
      
            foreach (FilterInfo filterInfo in devies)
            {
                Console.WriteLine(filterInfo.Name);
                VideoDevices.Add(filterInfo);
                
            }
         
            if (VideoDevices.Any())
            {
                CurrentDevice = VideoDevices[0];
            }
            else
            {
                MessageBox.Show("No video sources found", "Error", MessageBoxButton.OK, MessageBoxImage.Error);
            }
            
        }

        private void StartCameraPTz()
        {
            if (CurrentDevice != null)
            {
                if (_videoSource != null && _videoSource.IsRunning)
                {
                    _videoSource.SignalToStop();
                    _videoSource.WaitForStop();
                    
                }
            
                videodevice = new VideoCaptureDevice(CurrentDevice.MonikerString);
                Thread.Sleep(200);
                _videoSource = videodevice;
                _videoSource.NewFrame += video_NewFrame;
                _videoSource.Start();
            }
        }

        private void StopCameraPtz()
        {
            if (_videoSource != null && _videoSource.IsRunning)
            {
                _videoSource.SignalToStop();
                _videoSource.NewFrame -= new NewFrameEventHandler(video_NewFrame);
                _videoSource = null;
                
            }
        }

        protected void OnPropertyChanged(string propertyName)
        {
            PropertyChangedEventHandler handler = this.PropertyChanged;
            if (handler != null)
            {
                var e = new PropertyChangedEventArgs(propertyName);
                handler(this, e);
            }
        }