在ASP.Net MVC中使用C#从视频文件中获取视频元数据的最佳方法是什么？

Question

我已经在谷歌和StackOverflow上搜索了几个小时了。在StackOverflow上似乎有很多类似的问题，但它们都在3-5岁左右。

现在，使用FFMPEG仍然是从.NET web应用程序中的视频文件中提取元数据的最佳方法吗？如果是这样的话，最好的C#包装器是什么？

我试过MediaToolkit，MediaFile.dll，没有任何运气。我看到了，但它看起来几年没碰过了。

我还没有找到关于这个问题的任何最新数据。现在，从.NET最新版本中内置的视频中提取元数据的能力了吗？

在这一点上我基本上是在寻找方向。

我要补充的是，无论我使用什么，都可以每小时调用数千次，因此它必须是高效的。

Answer 1

看看MediaInfo项目(http://mediaarea.net/en/MediaInfo)

它获得关于大多数媒体类型的广泛信息，库与易于使用的c#助手类捆绑在一起。

您可以从这里下载windows的库和助手类：

http://mediaarea.net/en/MediaInfo/Download/Windows (无安装程序的DLL)

helper类位于Developers\Source\MediaInfoDLL\MediaInfoDLL.cs，只需将其添加到项目中并将MediaInfo.dll复制到bin中即可。

使用

您可以通过从库中请求特定参数来获取信息，下面是一个示例：

[STAThread]
static void Main(string[] Args)
{
    var mi = new MediaInfo();
    mi.Open(@"video path here");

    var videoInfo = new VideoInfo(mi);
    var audioInfo = new AudioInfo(mi);
     mi.Close();
}

public class VideoInfo 
{
    public string Codec { get; private set; }
    public int Width { get; private set; }
    public int Heigth { get; private set; }
    public double FrameRate { get; private set; }
    public string FrameRateMode { get; private set; }
    public string ScanType { get; private set; }
    public TimeSpan Duration { get; private set; }
    public int Bitrate { get; private set; }
    public string AspectRatioMode { get; private set; }
    public double AspectRatio { get; private set; }

    public VideoInfo(MediaInfo mi)
    {
        Codec=mi.Get(StreamKind.Video, 0, "Format");
        Width = int.Parse(mi.Get(StreamKind.Video, 0, "Width"));
        Heigth = int.Parse(mi.Get(StreamKind.Video, 0, "Height"));
        Duration = TimeSpan.FromMilliseconds(int.Parse(mi.Get(StreamKind.Video, 0, "Duration")));
        Bitrate = int.Parse(mi.Get(StreamKind.Video, 0, "BitRate"));
        AspectRatioMode = mi.Get(StreamKind.Video, 0, "AspectRatio/String"); //as formatted string
        AspectRatio =double.Parse(mi.Get(StreamKind.Video, 0, "AspectRatio"));
        FrameRate = double.Parse(mi.Get(StreamKind.Video, 0, "FrameRate"));
        FrameRateMode = mi.Get(StreamKind.Video, 0, "FrameRate_Mode");
        ScanType = mi.Get(StreamKind.Video, 0, "ScanType");
    }
}

public class AudioInfo
{
    public string Codec { get; private set; }
    public string CompressionMode { get; private set; }
    public string ChannelPositions { get; private set; }
    public TimeSpan Duration { get; private set; }
    public int Bitrate { get; private set; }
    public string BitrateMode { get; private set; }
    public int SamplingRate { get; private set; }

    public AudioInfo(MediaInfo mi)
    {
        Codec = mi.Get(StreamKind.Audio, 0, "Format");
        Duration = TimeSpan.FromMilliseconds(int.Parse(mi.Get(StreamKind.Audio, 0, "Duration")));
        Bitrate = int.Parse(mi.Get(StreamKind.Audio, 0, "BitRate"));
        BitrateMode = mi.Get(StreamKind.Audio, 0, "BitRate_Mode");
        CompressionMode = mi.Get(StreamKind.Audio, 0, "Compression_Mode");
        ChannelPositions = mi.Get(StreamKind.Audio, 0, "ChannelPositions");
        SamplingRate = int.Parse(mi.Get(StreamKind.Audio, 0, "SamplingRate"));
    }
}

您可以通过调用Inform()轻松地获得字符串格式的所有信息。

        var mi = new MediaInfo();
        mi.Open(@"video path here");
        Console.WriteLine(mi.Inform());
        mi.Close();

如果需要有关可用参数的更多信息，只需调用Options("Info_Parameters")查询所有参数即可。

        var mi = new MediaInfo();
        Console.WriteLine(mi.Option("Info_Parameters"));
        mi.Close();

Answer 2

可能有点晚了..。您可以使用NuGet包MediaToolKit使用最少的代码来完成这一任务。

要获得更多信息，请从这里MediaToolKit

Answer 3

我建议您对Process.Start使用ffmpeg，代码如下所示：

    private string GetVideoDuration(string ffmpegfile, string sourceFile) {
        using (System.Diagnostics.Process ffmpeg = new System.Diagnostics.Process()) {
            String duration;  // soon will hold our video's duration in the form "HH:MM:SS.UU"
            String result;  // temp variable holding a string representation of our video's duration
            StreamReader errorreader;  // StringWriter to hold output from ffmpeg

            // we want to execute the process without opening a shell
            ffmpeg.StartInfo.UseShellExecute = false;
            //ffmpeg.StartInfo.ErrorDialog = false;
            ffmpeg.StartInfo.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden;
            // redirect StandardError so we can parse it
            // for some reason the output comes through over StandardError
            ffmpeg.StartInfo.RedirectStandardError = true;

            // set the file name of our process, including the full path
            // (as well as quotes, as if you were calling it from the command-line)
            ffmpeg.StartInfo.FileName = ffmpegfile;

            // set the command-line arguments of our process, including full paths of any files
            // (as well as quotes, as if you were passing these arguments on the command-line)
            ffmpeg.StartInfo.Arguments = "-i " + sourceFile;

            // start the process
            ffmpeg.Start();

            // now that the process is started, we can redirect output to the StreamReader we defined
            errorreader = ffmpeg.StandardError;

            // wait until ffmpeg comes back
            ffmpeg.WaitForExit();

            // read the output from ffmpeg, which for some reason is found in Process.StandardError
            result = errorreader.ReadToEnd();

            // a little convoluded, this string manipulation...
            // working from the inside out, it:
            // takes a substring of result, starting from the end of the "Duration: " label contained within,
            // (execute "ffmpeg.exe -i somevideofile" on the command-line to verify for yourself that it is there)
            // and going the full length of the timestamp

            duration = result.Substring(result.IndexOf("Duration: ") + ("Duration: ").Length, ("00:00:00").Length);
            return duration;
        }
    }

希望它能帮上忙。