private static void OnNewFrame(GstVideoStream sender, IGstVideoFrameContext frameContext)
{
// if frame count is zero, reset interval start time
if (_intervalFrameCount == 0)
{
_startTime = System.DateTime.UtcNow;
}
// increment number of frames in the current interval
_intervalFrameCount++;
// if frame counter is equal to MeasureFPSOnFrameCount (300), calculate FPS and reset frame counter
if (_intervalFrameCount == MeasureFPSOnFrameCount)
{
var intervalSpan = System.DateTime.UtcNow - _startTime;
_intervalFps = _intervalFrameCount / intervalSpan.TotalSeconds;
_intervalFrameCount = 0;
}
/*
* Use frameContext.Buffer for accessing raw buffer as IntPtr.
* Make sure the format is what you expect by checking frameContext.Format (RGBA is the only supported one for now)
* Use frameContext.CopyTo for copying raw frame data to another unmanaged buffer (e.g. WritableBitmap)
*/
}
private static GstVideoStream _stream = null; // SGtreamer video stream object
static void Main(string[] args)
{
if (args.Length == 0)
{
Console.WriteLine($"Please provide GStreamer command line, camera index (--camera_index option) or source uri (--source_uri option).");
return;
}
try
{
var result = Parser.Default.ParseArguments <CommandLineOptions>(args);
result.WithParsed <CommandLineOptions>(options =>
{
if (options.CameraIndex != -1) // camera index specified
{
_stream = new GstVideoStream(options.CameraIndex, 0, 0);
}
else if (!string.IsNullOrEmpty(options.URI)) // URI source provided
{
_stream = new GstVideoStream(options.URI);
}
});
// if neither --camera_index nor --source_uri options were provided, pass the command line to GStreamer command line parser
if (_stream == null)
{
_stream = GstVideoStream.FromAppSinkCommandLine(string.Join(' ', args));
}
}
catch (GLib.GException ex)
{
Console.WriteLine($"GStreamer pipeline creating failure: {ex.Message}.");
return;
}
// creating heartbeat timer - for showing that the app is working and for printing FPS every MeasureFPSOnFrameCount (300) frames
_timer = new Timer(1000);
_timer.Elapsed += OnTimerElapsed;
Console.WriteLine($"{Environment.NewLine}Starting GStreamer video stream at {System.DateTime.Now}.{Environment.NewLine}Command line: {_stream.GstCommandLine}");
_stream.NewFrame += OnNewFrame; // new frame handler
_stream.Error += OnError; // error handler
_stream.EndOfStream += OnEOS; // end of stream handler
_stream.Play(); // start pipeline
_timer.Start(); // start timer
_started = true;
Console.WriteLine("Started");
// waiting for the end of stream or a stream error
_stream.WaitForMessageAsync(MessageType.Eos | MessageType.Error, TimeSpan.Zero).Wait();
Console.WriteLine($"{Environment.NewLine}Stream stopped at {System.DateTime.Now}.");
_timer.Stop();
_stream.Dispose();
}
private static void OnEOS(GstVideoStream sender)
{
Console.WriteLine($"{Environment.NewLine}=== End Of Stream ===");
}
private static void OnError(GstVideoStream sender, GLib.GException error, string debug)
{
Console.WriteLine($"{Environment.NewLine}ERROR: {error.Message} ({debug})");
}
