public byte[] GetVideoThumbnail(string inputFile, float frameTime, int width = -1, int height = -1)
{
InputFile = inputFile;
var settings = new FFmpegSettings
{
Seek = frameTime,
OutputFormat = "mjpeg",
VideoFrameSize = $"-vf scale={width}:{height}",
};
return(RunFFmpeg(inputFile, settings));
}
internal byte[] RunFFmpeg(string input, FFmpegSettings settings)
{
byte[] data;
try
{
var arguments = $" -hide_banner -loglevel panic -y -ss {settings.Seek.ToString(CultureInfo.InvariantCulture)} -i \"{input}\" -t 1 -f {settings.OutputFormat} -vframes 1 {settings.VideoFrameSize} \"-\"";
var processStartInfo =
new ProcessStartInfo(Utils.FfmpegPath, arguments)
{
WindowStyle = ProcessWindowStyle.Hidden,
CreateNoWindow = true,
UseShellExecute = false,
WorkingDirectory = Path.GetDirectoryName(Utils.FfmpegPath) ?? string.Empty,
RedirectStandardInput = true, //required to avoid ffmpeg printing to console
RedirectStandardOutput = true,
};
if (FFMpegProcess != null)
{
throw new InvalidOperationException();
}
FFMpegProcess = Process.Start(processStartInfo);
if (FFMpegProcess == null)
{
throw new FFMpegException(-1, "FFMpeg process was aborted");
}
var ms = new MemoryStream();
//start reading here, otherwise the streams fill up and ffmpeg will block forever
var imgDataTask = FFMpegProcess.StandardOutput.BaseStream.CopyToAsync(ms);
WaitFFMpegProcessForExit();
imgDataTask.Wait(1000);
data = ms.ToArray();
FFMpegProcess?.Close();
FFMpegProcess = null;
}
catch (Exception)
{
EnsureFFMpegProcessStopped();
throw;
}
return(data);
}
