startPlayerFromMic().

The τ Player API

`startPlayerFromMic()`

Dart API: startPlayerFromMic().

Starts the Microphone and plays what is recorded.

The Speaker is directely linked to the Microphone. There is no processing between the Microphone and the Speaker.

Tip: If you want to process the data before playing them, actually you must define a loop between a FlutterSoundPlayer and a FlutterSoundRecorder. (Please, look to this example).

startPlayerFromMic() has three optional parameters :

sampleRate: the Sample Rate used. Optional. Only used on Android. The default value is probably a good choice and the App can ommit this optional parameter.
numChannels: 1 for monophony, 2 for stereophony. Optional. Actually only monophony is implemented.
bufferSize: the size of the working buffer. This parameter is used on Android and iOS. The default value is 8192.

startPlayerFromMic() returns a Future, which is completed when the Player is really started.

Note: Several τ users needs to play on the headset what is recorded by the microphone, in quasi-real-time. I am convinced that implementing audio-graph will be the general solution and will be very elegant. But I think that we can implement this new simple verb startPlayerFromMic() before the great global solution. Later, we will implement the Tau Audio Graph concept, which will be a more general object.

This new example can be compared to the old loop example.

1. iOS

startPlayerFromMic() directely links the microphone to the headset inside the OS itself, without any processing by τ

The improvement is really good. The delay between what is recorded and what is played is much better.

2. Android

The link beetween the microphone and the headset is done inside τ-core. The messaging channels between Java and Dart is not involved. The audio data are just transfered from the recording-thread to the player thread.

This is a great disappointment : the performances are marginally improved. This means that implementing data transfert from/to Dart with FFI will not benefit from using FFI.

Example:

Dart
Javascript

     await myPlayer.startPlayerFromMic();
     ...
     myPlayer.stopPlayer();

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