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117 lines
6.1 KiB
117 lines
6.1 KiB
/*
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MixStereoToMono
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Created: Chip Audette, Jan 2017
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Purpose: Process audio mixing the Left and Right inputs into Mono.
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Demonstrates audio processing using floating point data type.
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Uses Teensy Audio Adapter.
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Assumes microphones (or whatever) are attached to the LINE IN (stereo)
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MIT License. use at your own risk.
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*/
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//These are the includes from the Teensy Audio Library
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#include <Audio.h> //Teensy Audio Librarya
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#include <Wire.h>
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#include <SPI.h>
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#include <SD.h>
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#include <SerialFlash.h>
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#include <OpenAudio_ArduinoLibrary.h> //for AudioConvert_I16toF32, AudioConvert_F32toI16, and AudioEffectGain_F32
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//create audio library objects for handling the audio
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AudioControlSGTL5000_Extended sgtl5000; //controller for the Teensy Audio Board
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AudioInputI2S i2s_in; //Digital audio *from* the Teensy Audio Board ADC. Sends Int16. Stereo.
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AudioOutputI2S i2s_out; //Digital audio *to* the Teensy Audio Board DAC. Expects Int16. Stereo
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AudioConvert_I16toF32 int2Float1, int2Float2; //Converts Int16 to Float. See class in AudioStream_F32.h
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AudioConvert_F32toI16 float2Int1, float2Int2; //Converts Float to Int16. See class in AudioStream_F32.h
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AudioMixer4_F32 mixer; //mix floating point data
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//Do you want to use the USB audio as your input, or do you want to use i2s as your input?
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#define DO_USB 1 //set to 1 to enable USB audio. Be sure to go under the "Tools" menu and do "USB Type" -> "Audio"
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#if DO_USB
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AudioInputUSB usb_in;
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AudioConnection patchCord1(usb_in, 0, int2Float1, 0);
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AudioConnection patchCord2(usb_in, 1, int2Float2, 0);
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#else
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AudioConnection patchCord1(i2s_in, 0, int2Float1, 0); //connect the Left input to the Left Int->Float converter
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AudioConnection patchCord2(i2s_in, 1, int2Float2, 0); //connect the Right input to the Right Int->Float converter
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#endif
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AudioConnection_F32 patchCord10(int2Float1, 0, mixer, 0); //Left. makes Float connections between objects
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AudioConnection_F32 patchCord11(int2Float2, 0, mixer, 1); //Right. makes Float connections between objects
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AudioConnection_F32 patchCord12(mixer, 0, float2Int1, 0); //Left. makes Float connections between objects
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AudioConnection_F32 patchCord13(mixer, 0, float2Int2, 0); //Right. makes Float connections between objects
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//For output, you always need an i2s or else you have no clock to drive the audio subsystem.
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//So, even if you're not going to use the headphone/line-out, you need these lines
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AudioConnection patchCord20(float2Int1, 0, i2s_out, 0); //connect the Left float processor to the Left output
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AudioConnection patchCord21(float2Int2, 0, i2s_out, 1); //connect the Right float processor to the Right output
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//Now, if you want USB output, it gets enabled here
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#if DO_USB
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AudioOutputUSB usb_out;
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AudioConnection patchCord30(float2Int1, 0, usb_out, 0); //connect the Left float processor to the Left output
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AudioConnection patchCord31(float2Int2, 0, usb_out, 1); //connect the Right float processor to the Right output
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#endif
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// which input on the audio shield will be used?
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const int myInput = AUDIO_INPUT_LINEIN;
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//const int myInput = AUDIO_INPUT_MIC;
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//define a function to setup the Teensy Audio Board how I like it
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void setupMyAudioBoard(void) {
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sgtl5000.enable(); //start the audio board
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sgtl5000.inputSelect(myInput); //choose line-in or mic-in
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sgtl5000.volume(0.8); //volume can be 0.0 to 1.0. 0.5 seems to be the usual default.
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sgtl5000.lineInLevel(10,10); //level can be 0 to 15. 5 is the Teensy Audio Library's default
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sgtl5000.adcHighPassFilterDisable(); //reduces noise. https://forum.pjrc.com/threads/27215-24-bit-audio-boards?p=78831&viewfull=1#post78831
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sgtl5000.micBiasEnable(3.0); //enable the mic bias voltage...only in AudioControlSGTL5000_Extended
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}
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// define the overall setup() function, the function that is called once when the device is booting
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void setup() {
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Serial.begin(115200); //open the USB serial link to enable debugging messages
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delay(500); //give the computer's USB serial system a moment to catch up.
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Serial.println("Teensy Hearing Aid: BasicCompressor_Float..."); //identify myself over the USB serial
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// Audio connections require memory, and the record queue
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// uses this memory to buffer incoming audio.
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AudioMemory(12); //allocate Int16 audio data blocks
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AudioMemory_F32(10); //allocate Float32 audio data blocks
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// Enable the audio shield, select input, and enable output
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setupMyAudioBoard();
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// set the gains on the mixer
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mixer.gain(0,0.5); //set gain to 0.5 (instead of 1.0) so that the mixer will never clip due to my two-channel mix
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mixer.gain(1,0.5); //set gain to 0.5 (instead of 1.0) so that the mixer will never clip due to my two-channel mix
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} //end setup()
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// define the loop() function, the function that is repeated over and over for the life of the device
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unsigned long curTime_millis = 0;
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unsigned long lastMemUpdate_millis=0;
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void loop() {
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//print status information to the Serial port
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curTime_millis = millis(); //what time is it right now
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if ((curTime_millis - lastMemUpdate_millis) < 0) lastMemUpdate_millis=0; //handle case where millis wraps around!
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if ((curTime_millis - lastMemUpdate_millis) > 2000) { // print a summary of the current & maximum usage
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printCPUandMemoryUsage(&Serial);
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lastMemUpdate_millis = curTime_millis; //we will use this value the next time around.
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}
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} //end loop();
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void printCPUandMemoryUsage(Stream *s) {
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s->print("Usage/Max: ");
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s->print("mixer CPU = "); s->print(mixer.processorUsage()); s->print("/"); s->print(mixer.processorUsageMax());s->print(", ");
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s->print("all CPU = " ); s->print(AudioProcessorUsage()); s->print("/"); s->print(AudioProcessorUsageMax());s->print(", ");
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s->print("Int16 Mem = ");s->print(AudioMemoryUsage()); s->print("/"); s->print(AudioMemoryUsageMax());s->print(", ");
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s->print("Float Mem = ");s->print(AudioMemoryUsage_F32());s->print("/"); s->print(AudioMemoryUsageMax_F32()); s->print(", ");
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s->println();
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};
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