/* TestCompressor2.ino Bob Larkin 23 January 2021 * * Test of AudioEffectCompressor2_F32 * See AudioEffectCompressor2_F32.h for much detail and explanation. * Choice of test signals is a single sine wave, a random sequence * of sine waves of varying frequency and amplitude, a power * sweep or a pulse of sine wave to see transient behavior. * * This version is for the Chip Audette OpenAudio_F32 Library. and * thus has that interface structure. * * NOTE: As of 23 January 2021, the compressor AudioEffectWDRC2_F32.h * was not finalized and could change in detail. Use here with * this in mind. */ #include "Audio.h" #include "OpenAudio_ArduinoLibrary.h" #define RANDOM 1 #define POWER_SWEEP 2 #define PULSE 3 #define ALTERNATE 4 // Edit in one of the last four, here: #define SIGNAL_SOURCE RANDOM AudioSynthWaveformSine_F32 sine1; // Test signal AudioEffectCompressor2_F32 compressor1; // Audio Compressor AudioEffectGain_F32 gain0; // Sets volume sent to output AudioEffectGain_F32 gain1; // Sets the same AudioOutputI2S_F32 i2sOut; AudioConnection_F32 patchCord1(sine1, 0, compressor1, 0); AudioConnection_F32 patchCord2(compressor1, 0, gain0, 0); AudioConnection_F32 patchCord3(compressor1, 0, gain1, 0); AudioConnection_F32 patchCord4(gain0, 0, i2sOut, 0); AudioConnection_F32 patchCord5(gain1, 0, i2sOut, 1); AudioControlSGTL5000 sgtl5000_1; uint16_t count17, count27; float level = 0.05f; void setup(void) { AudioMemory(50); AudioMemory_F32(100); Serial.begin(300); delay(1000); Serial.println("*** Test Compressor2 Gain Compressor **"); count17 = 0; count27 = 0; sine1.frequency(1000.0f); sine1.amplitude(0.05f); // CAUTION - If using ears on the output, adjust the following two carefully gain0.setGain_dB(-25.0f); // Consider (-50.0f); gain1.setGain_dB(-25.0f); // Consider (-50.0f); sgtl5000_1.enable(); int16_t delaySize = 256; // Any power of 2, i.e., 256, 128, 64, etc. compressor1.setDelayBufferSize(delaySize); // *** Here are four sample compressor curves. *** // Select by number here, and re-compile. #define COMPRESSOR_CURVE 1 #if COMPRESSOR_CURVE == 1 // Specify arbitrary 5-segment compression curve. An example of specifying // compressionCurve. See AudioEffectCompressor2_F32.h for more details. struct compressionCurve crv = { -2.0f, 0.0f, // margin, offset {0.0f, -10.0f, -20.0f, -30.0f, -1000.0f}, // kneeDB[] { 100.0f, 2.5f, 1.5f, 1.0f, 1.0f} }; // compressionRatio compressor1.setCompressionCurve(&crv); compressor1.begin(); #endif AudioEffectCompressor2_F32 *pc1 = &compressor1; // Needed for any *macro* defined curve. // Defines pointer to compressor1, called pc1 #if COMPRESSOR_CURVE == 2 // Sample of a limiter at -3 dB out for highest 15 dB, limiter macro limiterBegin(pc1, -3.0f, -15.0f); // pc1 is a pointer to compressor1 object #elif COMPRESSOR_CURVE == 3 // Another one, a basic compressor curve: // (pobject, linearInDB, compressionRatioDB) <- macro parameters basicCompressorBegin(pc1, -25.0f, 2.0); #elif COMPRESSOR_CURVE == 4 // And one using a high gain region as a squelch (but no clicks or pops) // (squelchIndB, linearInDB, compressionIndB, compressionRatioDB) <- macro parameters squelchCompressorBegin(pc1, -40.0f, -25.0f, -10.0f, 1.5f); #endif } void loop(void) { static uint16_t kk; #if SIGNAL_SOURCE == RANDOM /* To give an audio signal with interest, we alter the frequency * every 17 blocks (49 msec) and alter the level every 27 b;ocks * (78.4 msec) The pattern keeps changing to be more interesting * Janet thinks it is aliens. */ delay(3); // Serial.print(" CurInDB= "); Serial.print( compressor1.getCurrentInputDB(), 3); // Serial.print(" CurrentGainDB= "); Serial.println( compressor1.getCurrentGainDB(), 3); // Serial.print("Maximum Input = "); Serial.println(compressor1.getvInMaxDB()); if(count17++ == 17) { // Put a delay in, like between words if(randUniform() < 0.03) delay( (int)(1500.0*randUniform()) ); count17 = 0; float ff = 350.0f + 700.0f*sqrtf( randUniform() ); sine1.frequency(ff); //Serial.println(ff); } if(count27++ == 27) { count27 = 0; level = 1.0f*powf( randUniform(), 2 ); // 0 to 1, emphasizing 0 end sine1.amplitude(level); } #elif SIGNAL_SOURCE == POWER_SWEEP if(count17++ == 17) { count17 = 0; level *= 1.0592537f; // 0.5 dB delay(200); if(level > 1.0f) { level=0.001f; delay(500); } Serial.print( compressor1.getCurrentInputDB(), 3); Serial.print(","); Serial.println( compressor1.getCurrentGainDB(), 3); sine1.amplitude(level); } #elif SIGNAL_SOURCE == PULSE // A pulse, repeats every 3 minutes or so delay(3); if(count17 == 5) sine1.amplitude(0.0f); // Settling else if(count17 == 498) compressor1.printOn(true); //record it else if(count17 == 500) sine1.amplitude(0.03f); else if(count17 == 510) sine1.amplitude(0.0f); else if(count17 == 700) compressor1.printOn(false); // or build your own transient test pulse here count17++; #endif } /* randUniform() - Returns random number, uniform on (0, 1) * The "Even Quicker" uniform random sample generator from D. E. Knuth and * H. W. Lewis and described in Chapter 7 of "Numerical Receipes in C", * 2nd ed, with the comment "this is about as good as any 32-bit linear * congruential generator, entirely adequate for many uses." */ #define FL_ONE 0X3F800000 #define FL_MASK 0X007FFFFF float randUniform(void) { static uint32_t idum = 12345; union { uint32_t i32; float f32; } uinf; idum = (uint32_t)1664525 * idum + (uint32_t)1013904223; // return (*(float *)&it); // Cute convert to float but gets compiler warning uinf.i32 = FL_ONE | (FL_MASK & idum); // So do the same thing with a union return uinf.f32 - 1.0f; }