public CloneableAudioRecord([GeneratedEnum] AudioSource audioSource,
int sampleRateInHz,
[GeneratedEnum] ChannelIn channelConfig,
[GeneratedEnum] Android.Media.Encoding audioFormat,
int bufferSizeInBytes) : base(audioSource, sampleRateInHz, channelConfig, audioFormat, bufferSizeInBytes)
{
}
public string Prepare()
{
ChannelIn ch = ChannelIn.Mono;
if (CHANNELS == 2)
{
ch = ChannelIn.Stereo;
}
bufferSize = AudioRecord.GetMinBufferSize
(SAMPLING_RATE, ch, Android.Media.Encoding.Pcm16bit) * 3;
var recordingId = Guid.NewGuid().ToString();
var fileName = $"{recordingId}.{FILE_EXTENSION}";
endRecording = false;
audioBuffer = new System.Byte[bufferSize];
try
{
filePath = GetFullPathNameForRecording(fileName);
audioRecord = new AudioRecord(
// Hardware source of recording.
AudioSource.Mic,
// Frequency
SAMPLING_RATE,
// Mono or stereo
ch,
// Audio encoding
Android.Media.Encoding.Pcm16bit,
// Length of the audio clip.
audioBuffer.Length
);
output = new AudioFile()
{
FileName = fileName,
BitDepth = BIT_RATE,
SampleRate = SAMPLING_RATE,
NumberOfChannels = CHANNELS,
ContentType = MIME_TYPE,
};
currentState = State.Prepared;
return(recordingId);
}
catch (IllegalStateException e)
{
throw new RecordingException(e.ToString());
}
}
/// <summary>
/// Initializes a new instance of the <see cref="AudioStream"/> class.
/// </summary>
/// <param name="sampleRate">Sample rate.</param>
/// <param name="channels">The <see cref="ChannelIn"/> value representing the number of channels to record.</param>
/// <param name="audioFormat">The format of the recorded audio.</param>
public AudioStream(int sampleRate = 44100, ChannelIn channels = ChannelIn.Mono, Encoding audioFormat = Encoding.Pcm16bit)
{
bufferSize = AudioRecord.GetMinBufferSize(sampleRate, channels, audioFormat);
if (bufferSize < 0)
{
throw new Exception("Invalid buffer size calculated; audio settings used may not be supported on this device");
}
SampleRate = sampleRate;
this.channels = channels;
this.audioFormat = audioFormat;
}
public static AudioRecord FindAudioRecord(ref int sampleRate, ref Android.Media.Encoding audioFormat, ref ChannelIn channelConfig, ref int bufferSize)
{
foreach (int sr in _sampleRates)
{
foreach (var af in new Android.Media.Encoding[] { Android.Media.Encoding.Pcm16bit, Android.Media.Encoding.Pcm8bit })
{
foreach (var cc in new ChannelIn[] { ChannelIn.Stereo, ChannelIn.Mono })
{
try
{
// Log.Debug(C.TAG, "Attempting rate " + rate + "Hz, bits: " + audioFormat + ", channel: "
// + channelConfig);
int bs = AudioRecord.GetMinBufferSize(sr, cc, af);
if (bs > 0)
{
// check if we can instantiate and have a success
AudioRecord recorder = new AudioRecord(AudioSource.Default, sr, cc, af, bs);
if (recorder.State == State.Initialized)
{
bufferSize = bs;
sampleRate = sr;
audioFormat = af;
channelConfig = cc;
return recorder;
}
}
}
catch (Exception e)
{
// Log.e(C.TAG, rate + "Exception, keep trying.", e);
}
}
}
}
return null;
}
public static Supermortal.Common.PCL.Enums.ChannelConfiguration AndroidChannelConfigurationToChannelConfiguration(ChannelIn channelConfig)
{
if (channelConfig == ChannelIn.Mono)
return Supermortal.Common.PCL.Enums.ChannelConfiguration.Mono;
if (channelConfig == ChannelIn.Stereo)
return Supermortal.Common.PCL.Enums.ChannelConfiguration.Stereo;
return Supermortal.Common.PCL.Enums.ChannelConfiguration.Unknown;
}
/// <summary>
/// Starts the recording process.
/// </summary>
private async Task StartRecording()
{
if (isRecording)
{
// Already recording
return;
}
else
{
#region UWP
#if NETFX_CORE
// Prepare MediaRecorder and encoding profile
await SetupRecording();
var profile = MediaEncodingProfile.CreateWav(AudioEncodingQuality.Auto);
profile.Audio = AudioEncodingProperties.CreatePcm((uint)Parameters.SamplingRate, (uint)Parameters.Channels, 16);
// Start recording
isRecording = true;
await audioCapture.StartRecordToStreamAsync(profile, buffer);
return;
#endif
#endregion
#region ANDROID
#if __ANDROID__
// Setup recorder
ChannelIn channels = Parameters.Channels == 1 ? ChannelIn.Mono : ChannelIn.Stereo;
recorder = new AudioRecord(
AudioSource.Mic,
(int)Parameters.SamplingRate,
channels,
Android.Media.Encoding.Pcm16bit,
bufferLimit
);
// Start recording
isRecording = true;
int totalBytesRead = 0;
buffer = new byte[bufferLimit];
// lock buffer so that no other thread can acces the buffer (ie. replay while recording)
// and create inconsistent audio data
lock (bufferLock)
{
recorder.StartRecording();
// Record audio until buffer is full
while (totalBytesRead < bufferLimit)
{
try
{
totalBytesRead = recorder.Read(buffer, 0, bufferLimit);
if (totalBytesRead < 0)
{
throw new Exception(String.Format("Exception code: {0}", totalBytesRead));
}
}
catch (Exception e)
{
// Invalidate audio buffer
buffer = null;
break;
}
}
}
#endif
#endregion
}
}
