protected override IEnumerable<Datum> Poll(CancellationToken cancellationToken)
{
MediaRecorder recorder = null;
try
{
recorder = new MediaRecorder();
recorder.SetAudioSource(AudioSource.Mic);
recorder.SetOutputFormat(OutputFormat.ThreeGpp);
recorder.SetAudioEncoder(AudioEncoder.AmrNb);
recorder.SetOutputFile("/dev/null");
recorder.Prepare();
recorder.Start();
// mark start time of amplitude measurement -- MaxAmplitude is always computed from previous call to MaxAmplitude
int dummy = recorder.MaxAmplitude;
Thread.Sleep(SampleLengthMS);
return new Datum[] { new SoundDatum(DateTimeOffset.UtcNow, 20 * Math.Log10(recorder.MaxAmplitude)) }; // http://www.mathworks.com/help/signal/ref/mag2db.html
}
finally
{
if (recorder != null)
{
try { recorder.Stop(); }
catch (Exception) { }
try { recorder.Release(); }
catch (Exception) { }
}
}
}
protected override void OnCreate (Bundle bundle)
{
base.OnCreate (bundle);
SetContentView (Resource.Layout.video);
string path = Android.OS.Environment.ExternalStorageDirectory.AbsolutePath + "/test.mp4";
var record = FindViewById<Button> (Resource.Id.Record);
var stop = FindViewById<Button> (Resource.Id.Stop);
var play = FindViewById<Button> (Resource.Id.Play);
var video = FindViewById<VideoView> (Resource.Id.SampleVideoView);
record.Click += delegate {
video.StopPlayback ();
recorder = new MediaRecorder ();
recorder.SetVideoSource (VideoSource.Camera);
recorder.SetAudioSource (AudioSource.Mic);
recorder.SetOutputFormat (OutputFormat.Default);
recorder.SetVideoEncoder (VideoEncoder.Default);
recorder.SetAudioEncoder (AudioEncoder.Default);
recorder.SetOutputFile (path);
recorder.SetPreviewDisplay (video.Holder.Surface);
recorder.Prepare ();
recorder.Start ();
};
stop.Click += delegate {
if (recorder != null) {
recorder.Stop ();
recorder.Release ();
}
};
play.Click += delegate {
var uri = Android.Net.Uri.Parse (path);
video.SetVideoURI (uri);
video.Start ();
};
}
public void StopRecorder()
{
try
{
IsRecorderStop = true;
IsRecorderPlaying = false;
if (timer != null)
{
timer.Stop();
timer.Dispose();
timer = null;
}
if (mediaRecorder != null)
{
mediaRecorder.Stop();
mediaRecorder.Release();
mediaRecorder.Dispose();
mediaRecorder = null;
}
}
catch (System.Exception ex)
{
}
}
public void OnCompletion(MediaRecorder recorder)
{
f.Close();
if (!failed)
{
recorder.Reset();
recorder.Release();
try
{
System.IO.File.Move(tempFilename, outputFilename);
System.IO.File.Delete(tempFilename);
} catch
{
}
}
}
