/* TestEqualizer1.ino Bob Larkin 10 May 2020 * This is a test of the Filter Equalizer for Teensy Audio. * This version is for the Chip Audette _F32 Library. */ // Removed redundant DSP_TeensyAudio_F32.h Bob 9 Mar 2022 #include "Audio.h" #include "OpenAudio_ArduinoLibrary.h" AudioInputI2S i2s1; // Start interrupts AudioSynthWaveformSine_F32 sine1; // Test signal AudioFilterEqualizer_F32 equalize1; AudioRecordQueue_F32 queue1; // The LSB output AudioConnection_F32 patchCord1(sine1, 0, equalize1, 0); AudioConnection_F32 patchCord2(equalize1, 0, queue1, 0); //nBands = 10 This octave band equalizer is set strangely to demonstrate the Equalizer float fBand[] = { 40.0, 80.0, 160.0, 320.0, 640.0, 1280.0, 2560.0, 5120.0, 10240.0, 22058.5}; float dbBand[] = {10.0, 2.0, -2.0, -5.0, -2.0, -4.0, -20.0, 6.0, 10.0, -100}; float equalizeCoeffs[249]; float dt1[128]; float *pq1, *pd1; int i, k; float32_t dBResponse[500]; // Show lots of detail void setup(void) { AudioMemory(5); AudioMemory_F32(10); Serial.begin(300); delay(1000); Serial.println("*** Test Audio Equalizer ***"); sine1.frequency(1000.0f); // Initialize the equalizer with 10 bands, 199 FIR coefficients and -65 dB sidelobes uint16_t eq = equalize1.equalizerNew(10, &fBand[0], &dbBand[0], 199, &equalizeCoeffs[0], 65); if (eq == ERR_EQ_BANDS) Serial.println("Equalizer failed: Invalid number of frequency bands."); else if (eq == ERR_EQ_SIDELOBES) Serial.println("Equalizer failed: Invalid sidelobe specification."); else if (eq == ERR_EQ_NFIR) Serial.println("Equalizer failed: Invalid number of FIR coefficients."); else Serial.println("Equalizer initialized successfully."); // Get frequency response in dB for 500 points, uniformly spaced from 0 to 21058 Hz equalize1.getResponse(500, dBResponse); Serial.println("Freq Hz, Response dB"); for(int m=0; m<500; m++) { // Print the response in Hz, dB, suitable for a spread sheet Serial.print((float32_t)m * 22058.5f / 500.0f); Serial.print(","); Serial.println(dBResponse[m]); } i = -10; k=0; } void loop(void) { if(i<0) i++; // Get past startup if(i==0) queue1.begin(); // Collect 128 samples and output to Serial // This "if" will be active for i == 0 if (queue1.available() >= 1 && i >= 0) { pq1 = queue1.readBuffer(); pd1 = &dt1[0]; for(k=0; k<128; k++) { *pd1++ = *pq1++; } i=1; // Only collect 1 block Serial.print("Maximum F32 memory usage at loop:"); Serial.println( AudioMemoryUsageMax_F32() ); queue1.freeBuffer(); queue1.end(); // No more data to queue1 } if(i == 1) { // Uncomment the next 3 lines to printout a sample of the sine wave. /*Serial.println("128 Samples: "); for (k=0; k<128; k++) { Serial.println (dt1[k],7); */ } i = 2; delay(2); }