WPF另类实现摄像头录像

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

nginx-win-rtmp.conf配置文件内容如下：

#user  nobody;
# multiple workers works !
worker_processes  2;

#error_log  logs/error.log;
#error_log  logs/error.log  notice;
#error_log  logs/error.log  info;

#pid        logs/nginx.pid;
#worker_rlimit_nofile 100000;   #更改worker进程的最大打开文件数限制
                                               #如果没设置的话, 这个值为操作系统的限制.
                                               #设置后你的操作系统和Nginx可以处理比“ulimit -a”更多的文件
                                               #所以把这个值设高, 这样nginx就不会有“too many open files”问题了


events {
    worker_connections  8192;#设置可由一个worker进程同时打开的最大连接数
                              #如果设置了上面提到的worker_rlimit_nofile, 我们可以将这个值设得很高
    # max value 32768, nginx recycling connections+registry optimization = 
    #   this.value * 20 = max concurrent connections currently tested with one worker
    #   C1000K should be possible depending there is enough ram/cpu power
    # multi_accept on;
}

rtmp {
    server {
        listen 1935;#监听端口,若被占用,可以更改
        chunk_size 4000;#上传flv文件块儿的大小
        application live { #创建一个叫live的应用
             live on;#开启live的应用
             allow publish 127.0.0.1;#
             allow play all;
        }
    }
}

http {
    #include      /nginx/conf/naxsi_core.rules;
    include       mime.types;
    default_type  application/octet-stream;

    #log_format  main  '$remote_addr:$remote_port - $remote_user [$time_local] "$request" '
    #                  '$status $body_bytes_sent "$http_referer" '
    #                  '"$http_user_agent" "$http_x_forwarded_for"';

    #access_log  logs/access.log  main;

#     # loadbalancing PHP
#     upstream myLoadBalancer {
#         server 127.0.0.1:9001 weight=1 fail_timeout=5;
#         server 127.0.0.1:9002 weight=1 fail_timeout=5;
#         server 127.0.0.1:9003 weight=1 fail_timeout=5;
#         server 127.0.0.1:9004 weight=1 fail_timeout=5;
#         server 127.0.0.1:9005 weight=1 fail_timeout=5;
#         server 127.0.0.1:9006 weight=1 fail_timeout=5;
#         server 127.0.0.1:9007 weight=1 fail_timeout=5;
#         server 127.0.0.1:9008 weight=1 fail_timeout=5;
#         server 127.0.0.1:9009 weight=1 fail_timeout=5;
#         server 127.0.0.1:9010 weight=1 fail_timeout=5;
#         least_conn;
#     }

    sendfile        off;
    #tcp_nopush     on;

    server_names_hash_bucket_size 128;

## Start: Timeouts ##
    client_body_timeout   10;
    client_header_timeout 10;
    keepalive_timeout     30;
    send_timeout          10;
    keepalive_requests    10;
## End: Timeouts ##

    #gzip  on;

    server {
        listen       8088;
        server_name  localhost;

        #charset koi8-r;

        #access_log  logs/host.access.log  main;

        ## Caching Static Files, put before first location
        #location ~* .(jpg|jpeg|png|gif|ico|css|js)$ {
        #    expires 14d;
        #    add_header Vary Accept-Encoding;
        #}

# For Naxsi remove the single # line for learn mode, or the ## lines for full WAF mode
        location / {
            #include    /nginx/conf/mysite.rules; # see also http block naxsi include line
            ##SecRulesEnabled;
              ##DeniedUrl "/RequestDenied";
              ##CheckRule "$SQL >= 8" BLOCK;
              ##CheckRule "$RFI >= 8" BLOCK;
              ##CheckRule "$TRAVERSAL >= 4" BLOCK;
              ##CheckRule "$XSS >= 8" BLOCK;
            root   html;
            index  index.html index.htm;
        }

# For Naxsi remove the ## lines for full WAF mode, redirect location block used by naxsi
        ##location /RequestDenied {
        ##    return 412;
        ##}

## Lua examples !
#         location /robots.txt {
#           rewrite_by_lua '
#             if ngx.var.http_host ~= "localhost" then
#               return ngx.exec("/robots_disallow.txt");
#             end
#           ';
#         }

        #error_page  404              /404.html;

        # redirect server error pages to the static page /50x.html
        #
        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
            root   html;
        }

        # proxy the PHP scripts to Apache listening on 127.0.0.1:80
        #
        #location ~ .php$ {
        #    proxy_pass   http://127.0.0.1;
        #}

        # pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000
        #
        #location ~ .php$ {
        #    root           html;
        #    fastcgi_pass   127.0.0.1:9000; # single backend process
        #    fastcgi_pass   myLoadBalancer; # or multiple, see example above
        #    fastcgi_index  index.php;
        #    fastcgi_param  SCRIPT_FILENAME  $document_root$fastcgi_script_name;
        #    include        fastcgi_params;
        #}

        # deny access to .htaccess files, if Apache's document root
        # concurs with nginx's one
        #
        #location ~ /.ht {
        #    deny  all;
        #}
    }


    # another virtual host using mix of IP-, name-, and port-based configuration
    #
    #server {
    #    listen       8000;
    #    listen       somename:8080;
    #    server_name  somename  alias  another.alias;

    #    location / {
    #        root   html;
    #        index  index.html index.htm;
    #    }
    #}


    # HTTPS server
    #
    #server {
    #    listen       443 ssl spdy;
    #    server_name  localhost;

    #    ssl                  on;
    #    ssl_certificate      cert.pem;
    #    ssl_certificate_key  cert.key;

    #    ssl_session_timeout  5m;

    #    ssl_prefer_server_ciphers On;
    #    ssl_protocols TLSv1 TLSv1.1 TLSv1.2;
    #    ssl_ciphers ECDH+AESGCM:ECDH+AES256:ECDH+AES128:ECDH+3DES:RSA+AESGCM:RSA+AES:RSA+3DES:!aNULL:!eNULL:!MD5:!DSS:!EXP:!ADH:!LOW:!MEDIUM;

    #    location / {
    #        root   html;
    #        index  index.html index.htm;
    #    }
    #}

}

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:	est.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
ginx-win-rtmp.conf";
        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。