WPF中使用第三方控件来直接进行录像的控件没有找到（aforgenet好像不维护了？WPFMediaKit好像只能实现摄像头拍照。收费的控件没有使用，不做评论。）
通过百度（感谢：https://www.cnblogs.com/giserlong88/p/11244779.html），确定了可以通过FFmpeg+Nginx+Vlc.DotNet.Wpf可以实现摄像头的录像保存、录像预览（有延时），实现方案是，通过FFmpeg来实现录像并推送到Nginx搭建的rtmp流媒体服务器，然后WPF通过Vlc.DotNet.Wpf来拉取rtmp流服务器的内容来实现视频预览。
具体代码如下：
首先去下载FFmpeg（http://ffmpeg.org/download.html），Nginx（http://nginx.org/en/download.html），Nuget上引用Vlc.DotNet.Wpf，下载其所需要的libvlc播放器
把下载的FFmpeg、Nginx和libvlc放到Debug目录下。
目录结构如下
Debug
FFmpeg
ffmpeg.exe
……
Nginx
nginx.exe
……
libvlc
win-x64
……
win-x86
……
新建一个WPF项目，在MainWindow.xaml主要处理启动Nginx和进行推送
<Window x:Class="VideTest.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d"
Title="MainWindow" Height="450" Width="800" Loaded="MainWindow_OnLoaded">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="20"></RowDefinition>
<RowDefinition Height="*"></RowDefinition>
</Grid.RowDefinitions>
<WrapPanel>
<TextBox Name="SavePath" Text="D:\test.mp4" Width="94" HorizontalAlignment="Left"></TextBox>
<TextBox Name="VideoName" Text="罗技高清网络摄像机 C930c" Width="94" HorizontalAlignment="Left"></TextBox>
<TextBox Name="AudioName" Text="麦克风 (罗技高清网络摄像机 C930c)" Width="94" HorizontalAlignment="Left"></TextBox>
<Button Content="1、启动视频监控" HorizontalAlignment="Left" VerticalAlignment="Top" Width="107" Click="ButtonStart_OnClick"/>
<Button Content="2、开始录制" HorizontalAlignment="Left" VerticalAlignment="Top" Width="75" Click="ButtonSase_OnClick"/>
<TextBlock Text="开始录制后大概5秒主界面就可以看到监控视频"></TextBlock>
</WrapPanel>
<Border Grid.Row="1">
<Image x:Name="img"></Image>
</Border>
</Grid>
</Window>
文本框中的摄像头和麦克风，是使用下发的Load中的命令检测到的。
后台代码：
using System;
using System.Diagnostics;
using System.IO;
using System.Reflection;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using Vlc.DotNet.Core;
using Vlc.DotNet.Wpf;
namespace VideTest
{
/// <summary>
/// MainWindow.xaml 的交互逻辑
/// </summary>
public partial class MainWindow : Window
{
private readonly string ffmpegPath = $"{AppDomain.CurrentDomain.BaseDirectory}FFmpeg/ffmpeg.exe";
private readonly string nginxPath = @"nginx.exe -c conf\nginx-win-rtmp.conf &taskkill /f /im nginx.exe";
private VlcVideoSourceProvider sourceProvider;
public MainWindow()
{
InitializeComponent();
}
private void MediaPlayer_Log(object sender, VlcMediaPlayerLogEventArgs e)
{
var message = "libVlc : " + e.Level + e.Message + e.Module;
Debug.WriteLine(message);
}
private void MainWindow_OnLoaded(object sender, RoutedEventArgs e)
{
//var ffmpegPath = $"{AppDomain.CurrentDomain.BaseDirectory}FFmpeg/ffmpeg.exe"; //// 显示可用的音效设备 //var ffmpegArgument = " -list_devices true -f dshow -i dummy"; //var process = new System.Diagnostics.Process(); //var startInfo = new System.Diagnostics.ProcessStartInfo(); //startInfo.FileName = ffmpegPath; //startInfo.Arguments = ffmpegArgument; //startInfo.UseShellExecute = false; //startInfo.RedirectStandardOutput = true; //startInfo.RedirectStandardError = true; // 将 StandardErrorEncoding 改为 UTF-8后FFmpeg输出不会中文乱码 //startInfo.StandardErrorEncoding = System.Text.Encoding.UTF8; //process.EnableRaisingEvents = true; //process.StartInfo = startInfo; //process.Start(); // 显示FFMpeg输出的内容，从中取出视频和音频设备名称 //string output = process.StandardError.ReadToEnd(); //Debug.WriteLine(output); //process.WaitForExit();
}
private void ButtonSase_OnClick(object sender, RoutedEventArgs e)
{
var file=new FileInfo(SavePath.Text);
if(file.Exists) file.Delete();
var ffmpegArgument = $" -f dshow -i video=\"{VideoName.Text}\" -f dshow -i audio=\"{AudioName.Text}\" -vcodec libx264 -acodec aac -strict -2 \"{SavePath.Text}\" -f flv rtmp://127.0.0.1:1935/live/home";
Task.Run(() =>
{
var process = new Process();
var startInfo = new ProcessStartInfo
{
FileName = ffmpegPath,
Arguments = ffmpegArgument,
UseShellExecute = true,
RedirectStandardOutput = false
};
process.StartInfo = startInfo;
process.Start();
process.WaitForExit();
});
}
private void ButtonStart_OnClick(object sender, RoutedEventArgs e)
{
Task.Run(() =>
{
var process = new Process();
var startInfo = new ProcessStartInfo("cmd.exe")
{
WorkingDirectory= $@"{AppDomain.CurrentDomain.BaseDirectory}nginx",
UseShellExecute = false,
RedirectStandardInput = true
};
process.StartInfo = startInfo;
process.Start();
process.StandardInput.WriteLine(nginxPath);
process.StandardInput.AutoFlush = true;
process.WaitForExit();
});
Dispatcher?.Invoke(() =>
{
var currentAssembly = Assembly.GetEntryAssembly();
var currentDirectory = new FileInfo(currentAssembly.Location).DirectoryName;
var libDirectory = new DirectoryInfo(System.IO.Path.Combine(currentDirectory, "libvlc",
IntPtr.Size == 4 ? "win-x86" : "win-x64"));
sourceProvider = new VlcVideoSourceProvider(Dispatcher);
sourceProvider.CreatePlayer(libDirectory);
sourceProvider.MediaPlayer.Play("rtmp://127.0.0.1:1935/live/home");
sourceProvider.MediaPlayer.Log += MediaPlayer_Log;
sourceProvider.MediaPlayer.Manager.SetFullScreen(sourceProvider.MediaPlayer.Manager.CreateMediaPlayer(),
true);
var bing = new Binding {Source = sourceProvider, Path = new PropertyPath("VideoSource")};
img.SetBinding(Image.SourceProperty, bing);
});
MessageBox.Show("启动成功，请点击开始录制。");
}
}
}
这样按顺序点击1和2的按钮后，即可实现WPF的视频录制和预览录制的视频内容。
同时我们在APP.cs中重写退出事件，来在程序退出的时候结束Nginx进行。
public partial class App : Application
{
protected override void OnExit(ExitEventArgs e)
{
var process = new Process();
var startInfo = new ProcessStartInfo()
{
FileName = "taskkill",
Arguments = " /f /im nginx.exe",
UseShellExecute = false,
RedirectStandardInput = true
};
process.StartInfo = startInfo;
process.Start();
process.WaitForExit();
}
}
至此，我们就变现实现了WPF进行视频录制和预览录制的视频内容的功能。