boblark
4 years ago
parent
0232e199a8
commit
fb807bbec6
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#ifndef _AudioEffectFormantShiftFD_F32_h |
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#define _AudioEffectFormantShiftFD_F32_h |
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#include "AudioStream_F32.h" |
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#include <arm_math.h> |
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#include "FFT_Overlapped_F32.h" |
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class AudioEffectFormantShiftFD_F32 : public AudioStream_F32 |
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{ |
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public: |
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//constructors...a few different options. The usual one should be: AudioEffectFormantShiftFD_F32(const AudioSettings_F32 &settings, const int _N_FFT)
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AudioEffectFormantShiftFD_F32(void) : AudioStream_F32(1, inputQueueArray_f32) {}; |
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AudioEffectFormantShiftFD_F32(const AudioSettings_F32 &settings) : |
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AudioStream_F32(1, inputQueueArray_f32) { |
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sample_rate_Hz = settings.sample_rate_Hz; |
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} |
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AudioEffectFormantShiftFD_F32(const AudioSettings_F32 &settings, const int _N_FFT) : |
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AudioStream_F32(1, inputQueueArray_f32) { |
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setup(settings, _N_FFT); |
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} |
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//destructor...release all of the memory that has been allocated
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~AudioEffectFormantShiftFD_F32(void) { |
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if (complex_2N_buffer != NULL) delete complex_2N_buffer; |
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} |
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int setup(const AudioSettings_F32 &settings, const int _N_FFT) { |
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sample_rate_Hz = settings.sample_rate_Hz; |
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int N_FFT; |
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//setup the FFT and IFFT. If they return a negative FFT, it wasn't an allowed FFT size.
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N_FFT = myFFT.setup(settings, _N_FFT); //hopefully, we got the same N_FFT that we asked for
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if (N_FFT < 1) return N_FFT; |
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N_FFT = myIFFT.setup(settings, _N_FFT); //hopefully, we got the same N_FFT that we asked for
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if (N_FFT < 1) return N_FFT; |
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//decide windowing
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Serial.println("AudioEffectFormantShiftFD_F32: setting myFFT to use hanning..."); |
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(myFFT.getFFTObject())->useHanningWindow(); //applied prior to FFT
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#if 1 |
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if (myIFFT.getNBuffBlocks() > 3) { |
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Serial.println("AudioEffectFormantShiftFD_F32: setting myIFFT to use hanning..."); |
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(myIFFT.getIFFTObject())->useHanningWindow(); //window again after IFFT
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} |
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#endif |
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//print info about setup
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Serial.println("AudioEffectFormantShiftFD_F32: FFT parameters..."); |
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Serial.print(" : N_FFT = "); Serial.println(N_FFT); |
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Serial.print(" : audio_block_samples = "); Serial.println(settings.audio_block_samples); |
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Serial.print(" : FFT N_BUFF_BLOCKS = "); Serial.println(myFFT.getNBuffBlocks()); |
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Serial.print(" : IFFT N_BUFF_BLOCKS = "); Serial.println(myIFFT.getNBuffBlocks()); |
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Serial.print(" : FFT use window = "); Serial.println(myFFT.getFFTObject()->get_flagUseWindow()); |
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Serial.print(" : IFFT use window = "); Serial.println((myIFFT.getIFFTObject())->get_flagUseWindow()); |
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//allocate memory to hold frequency domain data
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complex_2N_buffer = new float32_t[2 * N_FFT]; |
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//we're done. return!
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enabled = 1; |
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return N_FFT; |
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} |
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//void setLowpassFreq_Hz(float freq_Hz) { lowpass_freq_Hz = freq_Hz; }
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//float getLowpassFreq_Hz(void) { return lowpass_freq_Hz; }
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float setScaleFactor(float scale_fac) { |
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if (scale_fac < 0.00001) scale_fac = 0.00001; |
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return shift_scale_fac = scale_fac; |
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} |
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float getScaleFactor(void) { |
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return shift_scale_fac; |
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} |
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virtual void update(void); |
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private: |
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int enabled = 0; |
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float32_t *complex_2N_buffer; |
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audio_block_f32_t *inputQueueArray_f32[1]; |
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FFT_Overlapped_F32 myFFT; |
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IFFT_Overlapped_F32 myIFFT; |
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float lowpass_freq_Hz = 1000.f; |
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float sample_rate_Hz = AUDIO_SAMPLE_RATE; |
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float shift_scale_fac = 1.0; //how much to shift formants (frequency multiplier). 1.0 is no shift
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}; |
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void AudioEffectFormantShiftFD_F32::update(void) |
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{ |
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//get a pointer to the latest data
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audio_block_f32_t *in_audio_block = AudioStream_F32::receiveReadOnly_f32(); |
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if (!in_audio_block) return; |
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//simply return the audio if this class hasn't been enabled
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if (!enabled) { |
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AudioStream_F32::transmit(in_audio_block); |
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AudioStream_F32::release(in_audio_block); |
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return; |
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} |
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//convert to frequency domain
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myFFT.execute(in_audio_block, complex_2N_buffer); |
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AudioStream_F32::release(in_audio_block); //We just passed ownership to myFFT, so release it here.
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// ////////////// Do your processing here!!!
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//define some variables
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int fftSize = myFFT.getNFFT(); |
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int N_2 = fftSize / 2 + 1; |
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int source_ind; // neg_dest_ind;
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float source_ind_float, interp_fac; |
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float new_mag, scale; |
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float orig_mag[N_2]; |
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//int max_source_ind = (int)(((float)N_2) * (10000.0 / (48000.0 / 2.0))); //highest frequency bin to grab from (Assuming 48kHz sample rate)
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#if 1 |
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float max_source_Hz = 10000.0; //highest frequency to use as source data
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int max_source_ind = min(int(max_source_Hz / sample_rate_Hz * fftSize + 0.5),N_2); |
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#else |
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int max_source_ind = N_2; //this line causes this feature to be defeated
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#endif |
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//get the magnitude for each FFT bin and store somewhere safes
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arm_cmplx_mag_f32(complex_2N_buffer, orig_mag, N_2); |
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//now, loop over each bin and compute the new magnitude based on shifting the formants
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for (int dest_ind = 1; dest_ind < N_2; dest_ind++) { //don't start at zero bin, keep it at its original
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//what is the source bin for the new magnitude for this current destination bin
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source_ind_float = (((float)dest_ind) / shift_scale_fac) + 0.5; |
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//source_ind = (int)(source_ind_float+0.5); //no interpolation but round to the neariest index
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//source_ind = min(max(source_ind,1),N_2-1);
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source_ind = min(max(1, (int)source_ind_float), N_2 - 2); //Chip: why -2 and not -1? Because later, for for the interpolation, we do a +1 and we want to stay within nyquist
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interp_fac = source_ind_float - (float)source_ind; |
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interp_fac = max(0.0, interp_fac); //this will be used in the interpolation in a few lines
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//what is the new magnitude
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new_mag = 0.0; scale = 0.0; |
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if (source_ind < max_source_ind) { |
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//interpolate in the original magnitude vector to find the new magnitude that we want
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//new_mag=orig_mag[source_ind]; //the magnitude that we desire
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//scale = new_mag / orig_mag[dest_ind];//compute the scale factor
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new_mag = orig_mag[source_ind]; |
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new_mag += interp_fac * (orig_mag[source_ind] - orig_mag[source_ind + 1]); |
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scale = new_mag / orig_mag[dest_ind]; |
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//apply scale factor
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complex_2N_buffer[2 * dest_ind] *= scale; //real
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complex_2N_buffer[2 * dest_ind + 1] *= scale; //imaginary
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} else { |
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complex_2N_buffer[2 * dest_ind] = 0.0; //real
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complex_2N_buffer[2 * dest_ind + 1] = 0.0; //imaginary
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} |
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//zero out the lowest bin
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complex_2N_buffer[0] = 0.0; //real
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complex_2N_buffer[1] = 0.0; //imaginary
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} |
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//rebuild the negative frequency space
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myFFT.rebuildNegativeFrequencySpace(complex_2N_buffer); //set the negative frequency space based on the positive
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// ///////////// End do your processing here
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//call the IFFT
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audio_block_f32_t *out_audio_block = myIFFT.execute(complex_2N_buffer); //out_block is pre-allocated in here.
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//send the returned audio block. Don't issue the release command here because myIFFT will re-use it
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AudioStream_F32::transmit(out_audio_block); //don't release this buffer because myIFFT re-uses it within its own code
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return; |
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}; |
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#endif |
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@ -0,0 +1,219 @@ |
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// FormantShifter_FD
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//
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// Demonstrate formant shifting via frequency domain processin.
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//
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// Created: Chip Audette (OpenAudio) March 2019
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//
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// Approach:
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// * Take samples in the time domain
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// * Take FFT to convert to frequency domain
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// * Manipulate the frequency bins to do the formant shifting
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// * Take IFFT to convert back to time domain
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// * Send samples back to the audio interface
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//
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// The amount of formant shifting is controled via the Serial link.
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// It defaults to a modest upward shifting of the formants
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//
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// Built for the Tympan library for Teensy 3.6-based hardware
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//
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// MIT License. Use at your own risk.
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//
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#include <Tympan_Library.h> |
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#include "AudioEffectFormantShiftFD_F32.h" //the local file holding your custom function |
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#include "SerialManager.h" |
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//set the sample rate and block size
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const float sample_rate_Hz = 44117.f; ; //24000 or 44117 (or other frequencies in the table in AudioOutputI2S_F32)
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const int audio_block_samples = 128; //for freq domain processing choose a power of 2 (16, 32, 64, 128) but no higher than 128
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AudioSettings_F32 audio_settings(sample_rate_Hz, audio_block_samples); |
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//create audio library objects for handling the audio
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Tympan audioHardware(TympanRev::D); //do TympanRev::C or TympanRev::D
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AudioInputI2S_F32 i2s_in(audio_settings); //Digital audio *from* the Tympan AIC.
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AudioEffectFormantShiftFD_F32 formantShift(audio_settings); //create the frequency-domain processing block
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AudioEffectGain_F32 gain1; //Applies digital gain to audio data.
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AudioOutputI2S_F32 i2s_out(audio_settings); //Digital audio out *to* the Tympan AIC.
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//Make all of the audio connections
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AudioConnection_F32 patchCord1(i2s_in, 0, formantShift, 0); //use the Left input
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AudioConnection_F32 patchCord2(formantShift, 0, gain1, 0); //connect to gain
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AudioConnection_F32 patchCord3(gain1, 0, i2s_out, 0); //connect to the left output
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AudioConnection_F32 patchCord4(gain1, 0, i2s_out, 1); //connect to the right output
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//control display and serial interaction
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bool enable_printCPUandMemory = false; |
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void togglePrintMemoryAndCPU(void) { enable_printCPUandMemory = !enable_printCPUandMemory; }; |
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SerialManager serialManager(audioHardware); |
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#define mySerial audioHardware //audioHardware is a printable stream!
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//inputs and levels
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float input_gain_dB = 20.0f; //gain on the microphone
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float formant_shift_gain_correction_dB = 0.0; //will be used to adjust for gain in formant shifter
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float vol_knob_gain_dB = 0.0; //will be overridden by volume knob
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void switchToPCBMics(void) { |
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mySerial.println("Switching to PCB Mics."); |
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audioHardware.inputSelect(TYMPAN_INPUT_ON_BOARD_MIC); // use the microphone jack - defaults to mic bias OFF
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audioHardware.setInputGain_dB(input_gain_dB); |
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} |
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void switchToLineInOnMicJack(void) { |
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mySerial.println("Switching to Line-in on Mic Jack."); |
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audioHardware.inputSelect(TYMPAN_INPUT_JACK_AS_LINEIN); // use the microphone jack - defaults to mic bias OFF
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audioHardware.setInputGain_dB(0.0); |
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} |
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void switchToMicInOnMicJack(void) { |
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mySerial.println("Switching to Mic-In on Mic Jack."); |
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audioHardware.inputSelect(TYMPAN_INPUT_JACK_AS_MIC); // use the microphone jack - defaults to mic bias OFF
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audioHardware.setInputGain_dB(input_gain_dB); |
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} |
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// define the setup() function, the function that is called once when the device is booting
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void setup() { |
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audioHardware.beginBothSerial(); delay(1000); |
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mySerial.println("FormantShifter: starting setup()..."); |
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mySerial.print(" : sample rate (Hz) = "); mySerial.println(audio_settings.sample_rate_Hz); |
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mySerial.print(" : block size (samples) = "); mySerial.println(audio_settings.audio_block_samples); |
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// Audio connections require memory to work. For more
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// detailed information, see the MemoryAndCpuUsage example
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AudioMemory_F32(40, audio_settings); |
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// Configure the frequency-domain algorithm
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int overlap_factor = 4; //set to 4 or 8 or either 75% overlap (4x) or 87.5% overlap (8x)
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int N_FFT = audio_block_samples * overlap_factor;
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formantShift.setup(audio_settings, N_FFT); //do after AudioMemory_F32();
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formantShift.setScaleFactor(1.5); //1.0 is no formant shifting.
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if (overlap_factor == 4) { |
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formant_shift_gain_correction_dB = -3.0; |
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} else if (overlap_factor == 8) { |
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formant_shift_gain_correction_dB = -9.0; |
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} |
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//Enable the Tympan to start the audio flowing!
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audioHardware.enable(); // activate AIC
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//setup DC-blocking highpass filter running in the ADC hardware itself
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float cutoff_Hz = 60.0; //set the default cutoff frequency for the highpass filter
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audioHardware.setHPFonADC(true,cutoff_Hz,audio_settings.sample_rate_Hz); //set to false to disble
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//Choose the desired input
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switchToPCBMics(); //use PCB mics as input
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//switchToMicInOnMicJack(); //use Mic jack as mic input (ie, with mic bias)
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//switchToLineInOnMicJack(); //use Mic jack as line input (ie, no mic bias)
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//Set the desired volume levels
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audioHardware.volume_dB(0); // headphone amplifier. -63.6 to +24 dB in 0.5dB steps.
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// configure the blue potentiometer
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servicePotentiometer(millis(),0); //update based on the knob setting the "0" is not relevant here.
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//finish the setup by printing the help menu to the serial connections
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serialManager.printHelp(); |
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} |
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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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void loop() { |
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//respond to Serial commands
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while (Serial.available()) serialManager.respondToByte((char)Serial.read()); //USB Serial
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//while (Serial1.available()) serialManager.respondToByte((char)Serial1.read()); //BT Serial
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//check the potentiometer
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servicePotentiometer(millis(), 100); //service the potentiometer every 100 msec
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//check to see whether to print the CPU and Memory Usage
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if (enable_printCPUandMemory) printCPUandMemory(millis(), 3000); //print every 3000 msec
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} //end loop();
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// ///////////////// Servicing routines
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//servicePotentiometer: listens to the blue potentiometer and sends the new pot value
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// to the audio processing algorithm as a control parameter
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void servicePotentiometer(unsigned long curTime_millis, const unsigned long updatePeriod_millis) { |
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//static unsigned long updatePeriod_millis = 100; //how many milliseconds between updating the potentiometer reading?
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static unsigned long lastUpdate_millis = 0; |
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static float prev_val = -1.0; |
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//has enough time passed to update everything?
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if (curTime_millis < lastUpdate_millis) lastUpdate_millis = 0; //handle wrap-around of the clock
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if ((curTime_millis - lastUpdate_millis) > updatePeriod_millis) { //is it time to update the user interface?
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//read potentiometer
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float val = float(audioHardware.readPotentiometer()) / 1023.0; //0.0 to 1.0
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val = (1.0/9.0) * (float)((int)(9.0 * val + 0.5)); //quantize so that it doesn't chatter...0 to 1.0
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//use the potentiometer value to control something interesting
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if (abs(val - prev_val) > 0.05) { //is it different than befor?
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prev_val = val; //save the value for comparison for the next time around
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#if 0 |
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//set the volume of the system
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setVolKnobGain_dB(val*45.0f - 10.0f - input_gain_dB); |
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#else |
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//set the amount of formant shifting
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float new_scale_fac = powf(2.0,(val-0.5)*2.0); |
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formantShift.setScaleFactor(new_scale_fac); |
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#endif |
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} |
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lastUpdate_millis = curTime_millis; |
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} // end if
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} //end servicePotentiometer();
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//This routine prints the current and maximum CPU usage and the current usage of the AudioMemory that has been allocated
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void printCPUandMemory(unsigned long curTime_millis, unsigned long updatePeriod_millis) { |
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//static unsigned long updatePeriod_millis = 3000; //how many milliseconds between updating gain reading?
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static unsigned long lastUpdate_millis = 0; |
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//has enough time passed to update everything?
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if (curTime_millis < lastUpdate_millis) lastUpdate_millis = 0; //handle wrap-around of the clock
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if ((curTime_millis - lastUpdate_millis) > updatePeriod_millis) { //is it time to update the user interface?
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mySerial.print("printCPUandMemory: "); |
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mySerial.print("CPU Cur/Peak: "); |
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mySerial.print(audio_settings.processorUsage()); |
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//mySerial.print(AudioProcessorUsage()); //if not using AudioSettings_F32
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mySerial.print("%/"); |
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mySerial.print(audio_settings.processorUsageMax()); |
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//mySerial.print(AudioProcessorUsageMax()); //if not using AudioSettings_F32
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mySerial.print("%, "); |
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mySerial.print("Dyn MEM Float32 Cur/Peak: "); |
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mySerial.print(AudioMemoryUsage_F32()); |
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mySerial.print("/"); |
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mySerial.print(AudioMemoryUsageMax_F32()); |
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mySerial.println(); |
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lastUpdate_millis = curTime_millis; //we will use this value the next time around.
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} |
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} |
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void printGainSettings(void) { |
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mySerial.print("Gain (dB): "); |
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mySerial.print("Vol Knob = "); mySerial.print(vol_knob_gain_dB,1); |
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//mySerial.print(", Input PGA = "); mySerial.print(input_gain_dB,1);
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mySerial.println(); |
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} |
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void incrementKnobGain(float increment_dB) { //"extern" to make it available to other files, such as SerialManager.h
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setVolKnobGain_dB(vol_knob_gain_dB+increment_dB); |
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} |
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void setVolKnobGain_dB(float gain_dB) { |
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vol_knob_gain_dB = gain_dB; |
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gain1.setGain_dB(vol_knob_gain_dB+formant_shift_gain_correction_dB); |
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printGainSettings(); |
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} |
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float incrementFormantShift(float incr_factor) { |
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float cur_scale_factor = formantShift.getScaleFactor(); |
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return formantShift.setScaleFactor(cur_scale_factor*incr_factor); |
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} |
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@ -0,0 +1,87 @@ |
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#ifndef _SerialManager_h |
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#define _SerialManager_h |
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#include <Tympan_Library.h> |
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//now, define the Serial Manager class
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class SerialManager { |
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public: |
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public: |
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SerialManager(Tympan &_audioHardware) |
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: audioHardware(_audioHardware) |
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{ }; |
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//SerialManager(void)
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//{ };
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void respondToByte(char c); |
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void printHelp(void); |
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int N_CHAN; |
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float channelGainIncrement_dB = 2.5f;
|
||||
float formantScaleIncrement = powf(2.0,1.0/6.0); |
||||
|
||||
private: |
||||
Tympan &audioHardware; |
||||
}; |
||||
#define thisSerial audioHardware |
||||
|
||||
void SerialManager::printHelp(void) {
|
||||
thisSerial.println(); |
||||
thisSerial.println("SerialManager Help: Available Commands:"); |
||||
thisSerial.println(" h: Print this help"); |
||||
thisSerial.println(" g: Print the gain settings of the device."); |
||||
thisSerial.println(" C: Toggle printing of CPU and Memory usage"); |
||||
thisSerial.println(" p: Switch to built-in PCB microphones"); |
||||
thisSerial.println(" m: switch to external mic via mic jack"); |
||||
thisSerial.println(" l: switch to line-in via mic jack"); |
||||
thisSerial.print(" k: Increase the gain of all channels (ie, knob gain) by "); thisSerial.print(channelGainIncrement_dB); thisSerial.println(" dB"); |
||||
thisSerial.print(" K: Decrease the gain of all channels (ie, knob gain) by ");thisSerial.print(-channelGainIncrement_dB); thisSerial.println(" dB"); |
||||
thisSerial.print(" f: Raise formant shifting (change by "); thisSerial.print(formantScaleIncrement); thisSerial.println("x)"); |
||||
thisSerial.print(" F: Lower formant shifting (change by "); thisSerial.print(1.0/formantScaleIncrement); thisSerial.println("x)"); thisSerial.println(); |
||||
} |
||||
|
||||
//functions in the main sketch that I want to call from here
|
||||
extern void incrementKnobGain(float); |
||||
extern void printGainSettings(void); |
||||
extern void togglePrintMemoryAndCPU(void); |
||||
extern float incrementFormantShift(float); |
||||
extern void switchToPCBMics(void); |
||||
extern void switchToMicInOnMicJack(void); |
||||
extern void switchToLineInOnMicJack(void); |
||||
|
||||
//switch yard to determine the desired action
|
||||
void SerialManager::respondToByte(char c) { |
||||
//float old_val = 0.0, new_val = 0.0;
|
||||
switch (c) { |
||||
case 'h': case '?': |
||||
printHelp(); break; |
||||
case 'g': case 'G': |
||||
printGainSettings(); break; |
||||
case 'k': |
||||
incrementKnobGain(channelGainIncrement_dB); break; |
||||
case 'K': //which is "shift k"
|
||||
incrementKnobGain(-channelGainIncrement_dB); break; |
||||
case 'C': case 'c': |
||||
thisSerial.println("Received: toggle printing of memory and CPU usage."); |
||||
togglePrintMemoryAndCPU(); break; |
||||
case 'p': |
||||
switchToPCBMics(); break; |
||||
case 'm': |
||||
switchToMicInOnMicJack(); break; |
||||
case 'l': |
||||
switchToLineInOnMicJack();break; |
||||
case 'f': |
||||
{ float new_val = incrementFormantShift(formantScaleIncrement); |
||||
thisSerial.print("Recieved: new format scale = "); thisSerial.println(new_val);} |
||||
break; |
||||
case 'F': |
||||
{ float new_val = incrementFormantShift(1./formantScaleIncrement); |
||||
thisSerial.print("Recieved: new format scale = "); thisSerial.println(new_val);} |
||||
break; |
||||
} |
||||
} |
||||
|
||||
|
||||
#endif |
||||
@ -0,0 +1,226 @@ |
||||
// FreqShifter_FD
|
||||
//
|
||||
// Demonstrate frequency shifting via frequency domain processin.
|
||||
//
|
||||
// Created: Chip Audette (OpenAudio) Aug 2019
|
||||
//
|
||||
// Approach: This processing is performed in the frequency domain.
|
||||
// Frequencies can only be shifted by an integer number of bins,
|
||||
// so small frequency shifts are not possible. For example, for
|
||||
// a sample rate of 44.1kHz, and when using N=256, one can only
|
||||
// shift frequencies in multiples of 44.1/256 = 172.3 Hz.
|
||||
//
|
||||
// This processing is performed in the frequency domain where
|
||||
// we take the FFT, shift the bins upward or downward, take
|
||||
// the IFFT, and listen to the results. In effect, this is
|
||||
// single sideband modulation, which will sound very unnatural
|
||||
// (like robot voices!). Maybe you'll like it, or maybe not.
|
||||
// Probably not, unless you like weird. ;)
|
||||
//
|
||||
// You can shift frequencies upward or downward with this algorithm.
|
||||
//
|
||||
// Frequency Domain Processing:
|
||||
// * Take samples in the time domain
|
||||
// * Take FFT to convert to frequency domain
|
||||
// * Manipulate the frequency bins to do the freqyebct shifting
|
||||
// * Take IFFT to convert back to time domain
|
||||
// * Send samples back to the audio interface
|
||||
//
|
||||
// Built for the Tympan library for Teensy 3.6-based hardware
|
||||
//
|
||||
// MIT License. Use at your own risk.
|
||||
//
|
||||
|
||||
#include <Tympan_Library.h> |
||||
#include "SerialManager.h" |
||||
|
||||
//set the sample rate and block size
|
||||
const float sample_rate_Hz = 44117.f; ; //24000 or 44117 (or other frequencies in the table in AudioOutputI2S_F32)
|
||||
const int audio_block_samples = 64; //for freq domain processing choose a power of 2 (16, 32, 64, 128) but no higher than 128
|
||||
AudioSettings_F32 audio_settings(sample_rate_Hz, audio_block_samples); |
||||
|
||||
//create audio library objects for handling the audio
|
||||
Tympan audioHardware(TympanRev::D); //do TympanRev::C or TympanRev::D
|
||||
AudioInputI2S_F32 i2s_in(audio_settings); //Digital audio *from* the Tympan AIC.
|
||||
AudioEffectFreqShiftFD_F32 freqShift(audio_settings); //create the frequency-domain processing block
|
||||
AudioEffectGain_F32 gain1; //Applies digital gain to audio data.
|
||||
AudioOutputI2S_F32 i2s_out(audio_settings); //Digital audio out *to* the Tympan AIC.
|
||||
|
||||
//Make all of the audio connections
|
||||
AudioConnection_F32 patchCord10(i2s_in, 0, freqShift, 0); //use the Left input
|
||||
AudioConnection_F32 patchCord20(freqShift, 0, gain1, 0); //connect to gain
|
||||
AudioConnection_F32 patchCord30(gain1, 0, i2s_out, 0); //connect to the left output
|
||||
AudioConnection_F32 patchCord40(gain1, 0, i2s_out, 1); //connect to the right output
|
||||
|
||||
|
||||
//control display and serial interaction
|
||||
bool enable_printCPUandMemory = false; |
||||
void togglePrintMemoryAndCPU(void) { enable_printCPUandMemory = !enable_printCPUandMemory; }; |
||||
SerialManager serialManager(audioHardware); |
||||
#define mySerial audioHardware //audioHardware is a printable stream!
|
||||
|
||||
//inputs and levels
|
||||
float input_gain_dB = 15.0f; //gain on the microphone
|
||||
float vol_knob_gain_dB = 0.0; //will be overridden by volume knob
|
||||
void switchToPCBMics(void) { |
||||
mySerial.println("Switching to PCB Mics."); |
||||
audioHardware.inputSelect(TYMPAN_INPUT_ON_BOARD_MIC); // use the microphone jack - defaults to mic bias OFF
|
||||
audioHardware.setInputGain_dB(input_gain_dB); |
||||
} |
||||
void switchToLineInOnMicJack(void) { |
||||
mySerial.println("Switching to Line-in on Mic Jack."); |
||||
audioHardware.inputSelect(TYMPAN_INPUT_JACK_AS_LINEIN); // use the microphone jack - defaults to mic bias OFF
|
||||
audioHardware.setInputGain_dB(0.0); |
||||
} |
||||
void switchToMicInOnMicJack(void) { |
||||
mySerial.println("Switching to Mic-In on Mic Jack."); |
||||
audioHardware.inputSelect(TYMPAN_INPUT_JACK_AS_MIC); // use the microphone jack - defaults to mic bias OFF
|
||||
audioHardware.setEnableStereoExtMicBias(true); //put the mic bias on both channels
|
||||
audioHardware.setInputGain_dB(input_gain_dB); |
||||
} |
||||
|
||||
// define the setup() function, the function that is called once when the device is booting
|
||||
void setup() { |
||||
audioHardware.beginBothSerial(); delay(1000); |
||||
mySerial.println("freqShifter: starting setup()..."); |
||||
mySerial.print(" : sample rate (Hz) = "); mySerial.println(audio_settings.sample_rate_Hz); |
||||
mySerial.print(" : block size (samples) = "); mySerial.println(audio_settings.audio_block_samples); |
||||
|
||||
// Audio connections require memory to work. For more
|
||||
// detailed information, see the MemoryAndCpuUsage example
|
||||
AudioMemory_F32(40, audio_settings); |
||||
|
||||
// Configure the FFT parameters algorithm
|
||||
int overlap_factor = 4; //set to 2, 4 or 8...which yields 50%, 75%, or 87.5% overlap (8x)
|
||||
int N_FFT = audio_block_samples * overlap_factor;
|
||||
Serial.print(" : N_FFT = "); Serial.println(N_FFT); |
||||
freqShift.setup(audio_settings, N_FFT); //do after AudioMemory_F32();
|
||||
|
||||
//configure the frequency shifting
|
||||
float shiftFreq_Hz = 750.0; //shift audio upward a bit
|
||||
float Hz_per_bin = audio_settings.sample_rate_Hz / ((float)N_FFT); |
||||
int shift_bins = (int)(shiftFreq_Hz / Hz_per_bin + 0.5); //round to nearest bin
|
||||
shiftFreq_Hz = shift_bins * Hz_per_bin; |
||||
Serial.print("Setting shift to "); Serial.print(shiftFreq_Hz); Serial.print(" Hz, which is "); Serial.print(shift_bins); Serial.println(" bins"); |
||||
freqShift.setShift_bins(shift_bins); //0 is no ffreq shifting.
|
||||
|
||||
//Enable the Tympan to start the audio flowing!
|
||||
audioHardware.enable(); // activate AIC
|
||||
|
||||
//setup DC-blocking highpass filter running in the ADC hardware itself
|
||||
float cutoff_Hz = 60.0; //set the default cutoff frequency for the highpass filter
|
||||
audioHardware.setHPFonADC(true,cutoff_Hz,audio_settings.sample_rate_Hz); //set to false to disble
|
||||
|
||||
//Choose the desired input
|
||||
switchToPCBMics(); //use PCB mics as input
|
||||
//switchToMicInOnMicJack(); //use Mic jack as mic input (ie, with mic bias)
|
||||
//switchToLineInOnMicJack(); //use Mic jack as line input (ie, no mic bias)
|
||||
|
||||
//Set the desired volume levels
|
||||
audioHardware.volume_dB(0); // headphone amplifier. -63.6 to +24 dB in 0.5dB steps.
|
||||
|
||||
// configure the blue potentiometer
|
||||
servicePotentiometer(millis(),0); //update based on the knob setting the "0" is not relevant here.
|
||||
|
||||
//finish the setup by printing the help menu to the serial connections
|
||||
serialManager.printHelp(); |
||||
} |
||||
|
||||
|
||||
// define the loop() function, the function that is repeated over and over for the life of the device
|
||||
void loop() { |
||||
|
||||
//respond to Serial commands
|
||||
while (Serial.available()) serialManager.respondToByte((char)Serial.read()); //USB Serial
|
||||
//while (Serial1.available()) serialManager.respondToByte((char)Serial1.read()); //BT Serial
|
||||
|
||||
//check the potentiometer
|
||||
servicePotentiometer(millis(), 100); //service the potentiometer every 100 msec
|
||||
|
||||
//check to see whether to print the CPU and Memory Usage
|
||||
if (enable_printCPUandMemory) printCPUandMemory(millis(), 3000); //print every 3000 msec
|
||||
|
||||
} //end loop();
|
||||
|
||||
|
||||
// ///////////////// Servicing routines
|
||||
|
||||
//servicePotentiometer: listens to the blue potentiometer and sends the new pot value
|
||||
// to the audio processing algorithm as a control parameter
|
||||
void servicePotentiometer(unsigned long curTime_millis, const unsigned long updatePeriod_millis) { |
||||
//static unsigned long updatePeriod_millis = 100; //how many milliseconds between updating the potentiometer reading?
|
||||
static unsigned long lastUpdate_millis = 0; |
||||
static float prev_val = -1.0; |
||||
|
||||
//has enough time passed to update everything?
|
||||
if (curTime_millis < lastUpdate_millis) lastUpdate_millis = 0; //handle wrap-around of the clock
|
||||
if ((curTime_millis - lastUpdate_millis) > updatePeriod_millis) { //is it time to update the user interface?
|
||||
|
||||
//read potentiometer
|
||||
float val = float(audioHardware.readPotentiometer()) / 1023.0; //0.0 to 1.0
|
||||
val = (1.0/9.0) * (float)((int)(9.0 * val + 0.5)); //quantize so that it doesn't chatter...0 to 1.0
|
||||
|
||||
//use the potentiometer value to control something interesting
|
||||
if (abs(val - prev_val) > 0.05) { //is it different than befor?
|
||||
prev_val = val; //save the value for comparison for the next time around
|
||||
|
||||
//change the volume
|
||||
float vol_dB = 0.f + 30.0f * ((val - 0.5) * 2.0); //set volume as 0dB +/- 30 dB
|
||||
audioHardware.print("Changing output volume to = "); audioHardware.print(vol_dB); audioHardware.println(" dB"); |
||||
audioHardware.volume_dB(vol_dB); |
||||
|
||||
} |
||||
|
||||
|
||||
lastUpdate_millis = curTime_millis; |
||||
} // end if
|
||||
} //end servicePotentiometer();
|
||||
|
||||
|
||||
|
||||
//This routine prints the current and maximum CPU usage and the current usage of the AudioMemory that has been allocated
|
||||
void printCPUandMemory(unsigned long curTime_millis, unsigned long updatePeriod_millis) { |
||||
//static unsigned long updatePeriod_millis = 3000; //how many milliseconds between updating gain reading?
|
||||
static unsigned long lastUpdate_millis = 0; |
||||
|
||||
//has enough time passed to update everything?
|
||||
if (curTime_millis < lastUpdate_millis) lastUpdate_millis = 0; //handle wrap-around of the clock
|
||||
if ((curTime_millis - lastUpdate_millis) > updatePeriod_millis) { //is it time to update the user interface?
|
||||
mySerial.print("printCPUandMemory: "); |
||||
mySerial.print("CPU Cur/Peak: "); |
||||
mySerial.print(audio_settings.processorUsage()); |
||||
mySerial.print("%/"); |
||||
mySerial.print(audio_settings.processorUsageMax()); |
||||
mySerial.print("%, "); |
||||
mySerial.print("Dyn MEM Float32 Cur/Peak: "); |
||||
mySerial.print(AudioMemoryUsage_F32()); |
||||
mySerial.print("/"); |
||||
mySerial.print(AudioMemoryUsageMax_F32()); |
||||
mySerial.println(); |
||||
|
||||
lastUpdate_millis = curTime_millis; //we will use this value the next time around.
|
||||
} |
||||
} |
||||
|
||||
void printGainSettings(void) { |
||||
mySerial.print("Gain (dB): "); |
||||
mySerial.print("Vol Knob = "); mySerial.print(vol_knob_gain_dB,1); |
||||
//mySerial.print(", Input PGA = "); mySerial.print(input_gain_dB,1);
|
||||
mySerial.println(); |
||||
} |
||||
|
||||
|
||||
void incrementKnobGain(float increment_dB) { //"extern" to make it available to other files, such as SerialManager.h
|
||||
setVolKnobGain_dB(vol_knob_gain_dB+increment_dB); |
||||
} |
||||
|
||||
void setVolKnobGain_dB(float gain_dB) { |
||||
vol_knob_gain_dB = gain_dB; |
||||
gain1.setGain_dB(vol_knob_gain_dB); |
||||
printGainSettings(); |
||||
} |
||||
|
||||
int incrementFreqShift(int incr_factor) { |
||||
int cur_shift_bins = freqShift.getShift_bins(); |
||||
return freqShift.setShift_bins(cur_shift_bins + incr_factor); |
||||
} |
||||
@ -0,0 +1,87 @@ |
||||
|
||||
|
||||
#ifndef _SerialManager_h |
||||
#define _SerialManager_h |
||||
|
||||
#include <Tympan_Library.h> |
||||
|
||||
|
||||
//now, define the Serial Manager class
|
||||
class SerialManager { |
||||
public: |
||||
public: |
||||
SerialManager(Tympan &_audioHardware) |
||||
: audioHardware(_audioHardware) |
||||
{ }; |
||||
//SerialManager(void)
|
||||
//{ };
|
||||
|
||||
void respondToByte(char c); |
||||
void printHelp(void); |
||||
int N_CHAN; |
||||
float channelGainIncrement_dB = 2.5f;
|
||||
int freq_shift_increment = 1; |
||||
|
||||
private: |
||||
Tympan &audioHardware; |
||||
}; |
||||
#define thisSerial audioHardware |
||||
|
||||
void SerialManager::printHelp(void) {
|
||||
thisSerial.println(); |
||||
thisSerial.println("SerialManager Help: Available Commands:"); |
||||
thisSerial.println(" h: Print this help"); |
||||
thisSerial.println(" g: Print the gain settings of the device."); |
||||
thisSerial.println(" C: Toggle printing of CPU and Memory usage"); |
||||
thisSerial.println(" p: Switch to built-in PCB microphones"); |
||||
thisSerial.println(" m: switch to external mic via mic jack"); |
||||
thisSerial.println(" l: switch to line-in via mic jack"); |
||||
thisSerial.print(" k: Increase the gain of all channels (ie, knob gain) by "); thisSerial.print(channelGainIncrement_dB); thisSerial.println(" dB"); |
||||
thisSerial.print(" K: Decrease the gain of all channels (ie, knob gain) by ");thisSerial.print(-channelGainIncrement_dB); thisSerial.println(" dB"); |
||||
thisSerial.print(" f: Raise freq shifting (change by "); thisSerial.print(freq_shift_increment); thisSerial.println(" bins)"); |
||||
thisSerial.print(" F: Lower freq shifting (change by "); thisSerial.print(-freq_shift_increment); thisSerial.println(" bins)"); thisSerial.println(); |
||||
} |
||||
|
||||
//functions in the main sketch that I want to call from here
|
||||
extern void incrementKnobGain(float); |
||||
extern void printGainSettings(void); |
||||
extern void togglePrintMemoryAndCPU(void); |
||||
extern int incrementFreqShift(int); |
||||
extern void switchToPCBMics(void); |
||||
extern void switchToMicInOnMicJack(void); |
||||
extern void switchToLineInOnMicJack(void); |
||||
|
||||
//switch yard to determine the desired action
|
||||
void SerialManager::respondToByte(char c) { |
||||
//float old_val = 0.0, new_val = 0.0;
|
||||
switch (c) { |
||||
case 'h': case '?': |
||||
printHelp(); break; |
||||
case 'g': case 'G': |
||||
printGainSettings(); break; |
||||
case 'k': |
||||
incrementKnobGain(channelGainIncrement_dB); break; |
||||
case 'K': //which is "shift k"
|
||||
incrementKnobGain(-channelGainIncrement_dB); break; |
||||
case 'C': case 'c': |
||||
thisSerial.println("Received: toggle printing of memory and CPU usage."); |
||||
togglePrintMemoryAndCPU(); break; |
||||
case 'p': |
||||
switchToPCBMics(); break; |
||||
case 'm': |
||||
switchToMicInOnMicJack(); break; |
||||
case 'l': |
||||
switchToLineInOnMicJack();break; |
||||
case 'f': |
||||
{ int new_val = incrementFreqShift(freq_shift_increment); |
||||
thisSerial.print("Recieved: new freq shift = "); thisSerial.println(new_val);} |
||||
break; |
||||
case 'F': |
||||
{ int new_val = incrementFreqShift(-freq_shift_increment); |
||||
thisSerial.print("Recieved: new freq shift = "); thisSerial.println(new_val);} |
||||
break; |
||||
} |
||||
} |
||||
|
||||
|
||||
#endif |
||||
@ -0,0 +1,125 @@ |
||||
/*
|
||||
* This include is NOT global to the OpenAudio library, but supports |
||||
* LowpassFilter_FD.ino |
||||
*/ |
||||
#ifndef _AudioEffectLowpassFD_F32_h |
||||
#define _AudioEffectLowpassFD_F32_h |
||||
|
||||
#include "AudioStream_F32.h" |
||||
#include <arm_math.h> |
||||
#include "FFT_Overlapped_OA_F32.h" |
||||
|
||||
class AudioEffectLowpassFD_F32 : public AudioStream_F32 |
||||
{ |
||||
public: |
||||
// constructors...a few different options. The usual one should be:
|
||||
// AudioEffectLowpassFD_F32(const AudioSettings_F32 &settings, const int _N_FFT)
|
||||
AudioEffectLowpassFD_F32(void) : AudioStream_F32(1, inputQueueArray_f32) {}; |
||||
AudioEffectLowpassFD_F32(const AudioSettings_F32 &settings) : |
||||
AudioStream_F32(1, inputQueueArray_f32) { sample_rate_Hz = settings.sample_rate_Hz; } |
||||
AudioEffectLowpassFD_F32(const AudioSettings_F32 &settings, const int _N_FFT) :
|
||||
AudioStream_F32(1, inputQueueArray_f32) { setup(settings,_N_FFT); } |
||||
|
||||
//destructor...release all of the memory that has been allocated
|
||||
~AudioEffectLowpassFD_F32(void) { |
||||
if (complex_2N_buffer != NULL) delete complex_2N_buffer; |
||||
} |
||||
|
||||
int setup(const AudioSettings_F32 &settings, const int _N_FFT) { |
||||
sample_rate_Hz = settings.sample_rate_Hz; |
||||
int N_FFT; |
||||
|
||||
//setup the FFT and IFFT. If they return a negative FFT, it wasn't an allowed FFT size.
|
||||
N_FFT = myFFT.setup(settings,_N_FFT); //hopefully, we got the same N_FFT that we asked for
|
||||
if (N_FFT < 1) return N_FFT; |
||||
N_FFT = myIFFT.setup(settings,_N_FFT); //hopefully, we got the same N_FFT that we asked for
|
||||
if (N_FFT < 1) return N_FFT; |
||||
|
||||
//decide windowing
|
||||
Serial.println("AudioEffectLowpassFD_F32: setting myFFT to use hanning..."); |
||||
(myFFT.getFFTObject())->useHanningWindow(); //applied prior to FFT
|
||||
//if (myIFFT.getNBuffBlocks() > 3) {
|
||||
// Serial.println("AudioEffectLowpassFD_F32: setting myIFFT to use hanning...");
|
||||
// (myIFFT.getIFFTObject())->useHanningWindow(); //window again after IFFT
|
||||
//}
|
||||
|
||||
//print info about setup
|
||||
Serial.println("AudioEffectLowpassFD_F32: FFT parameters..."); |
||||
Serial.print(" : N_FFT = "); Serial.println(N_FFT); |
||||
Serial.print(" : audio_block_samples = "); Serial.println(settings.audio_block_samples); |
||||
Serial.print(" : FFT N_BUFF_BLOCKS = "); Serial.println(myFFT.getNBuffBlocks()); |
||||
Serial.print(" : IFFT N_BUFF_BLOCKS = "); Serial.println(myIFFT.getNBuffBlocks()); |
||||
Serial.print(" : FFT use window = "); Serial.println(myFFT.getFFTObject()->get_flagUseWindow()); |
||||
Serial.print(" : IFFT use window = "); Serial.println((myIFFT.getIFFTObject())->get_flagUseWindow()); |
||||
|
||||
//allocate memory to hold frequency domain data
|
||||
complex_2N_buffer = new float32_t[2*N_FFT]; |
||||
|
||||
//we're done. return!
|
||||
enabled=1; |
||||
return N_FFT; |
||||
} |
||||
|
||||
void setLowpassFreq_Hz(float freq_Hz) { lowpass_freq_Hz = freq_Hz; } |
||||
|
||||
float getLowpassFreq_Hz(void) { return lowpass_freq_Hz; } |
||||
|
||||
virtual void update(void); |
||||
|
||||
private: |
||||
int enabled=0; |
||||
float32_t *complex_2N_buffer; |
||||
audio_block_f32_t *inputQueueArray_f32[1]; |
||||
FFT_Overlapped_OA_F32 myFFT; |
||||
IFFT_Overlapped_OA_F32 myIFFT; |
||||
float lowpass_freq_Hz = 1000.f; |
||||
float sample_rate_Hz = AUDIO_SAMPLE_RATE;
|
||||
}; |
||||
|
||||
|
||||
void AudioEffectLowpassFD_F32::update(void) |
||||
{ |
||||
//get a pointer to the latest data
|
||||
audio_block_f32_t *in_audio_block = AudioStream_F32::receiveReadOnly_f32(); |
||||
if (!in_audio_block) return; |
||||
|
||||
//simply return the audio if this class hasn't been enabled
|
||||
if (!enabled) { AudioStream_F32::transmit(in_audio_block); AudioStream_F32::release(in_audio_block); return; } |
||||
|
||||
//convert to frequency domain
|
||||
myFFT.execute(in_audio_block, complex_2N_buffer); |
||||
AudioStream_F32::release(in_audio_block); //We just passed ownership to myFFT, so release it here.
|
||||
|
||||
// ////////////// Do your processing here!!!
|
||||
|
||||
//this is lowpass, so zero the bins above the cutoff
|
||||
int NFFT = myFFT.getNFFT(); |
||||
int nyquist_bin = NFFT/2 + 1; |
||||
float bin_width_Hz = sample_rate_Hz / ((float)NFFT); |
||||
int cutoff_bin = (int)(lowpass_freq_Hz / bin_width_Hz + 0.5); //the 0.5 is so that it rounds instead of truncates
|
||||
if (cutoff_bin < nyquist_bin) { |
||||
for (int i=cutoff_bin; i < nyquist_bin; i++) { //only do positive frequency space...will rebuild the neg freq space later
|
||||
#if 0 |
||||
//zero out the bins (silence
|
||||
complex_2N_buffer[2*i] = 0.0f; //real
|
||||
complex_2N_buffer[2*i+1]= 0.0f; //imaginary
|
||||
#else |
||||
//attenuate by 30 dB
|
||||
complex_2N_buffer[2*i] *= 0.03f; //real
|
||||
complex_2N_buffer[2*i+1] *= 0.03f; //imaginary
|
||||
#endif |
||||
} |
||||
} |
||||
myFFT.rebuildNegativeFrequencySpace(complex_2N_buffer); //set the negative frequency space based on the positive
|
||||
|
||||
// ///////////// End do your processing here
|
||||
|
||||
//call the IFFT
|
||||
audio_block_f32_t *out_audio_block = myIFFT.execute(complex_2N_buffer); //out_block is pre-allocated in here.
|
||||
|
||||
|
||||
//send the returned audio block. Don't issue the release command here because myIFFT will re-use it
|
||||
AudioStream_F32::transmit(out_audio_block); //don't release this buffer because myIFFT re-uses it within its own code
|
||||
return; |
||||
}; |
||||
#endif |
||||
@ -0,0 +1,114 @@ |
||||
/* LowpassFilter_FD.ino
|
||||
* |
||||
* Demonstrate audio procesing in the frequency domain. |
||||
* |
||||
* Created: Chip Audette Sept-Oct 2016 for Tympan Library |
||||
* Approach: |
||||
* Take samples in the time domain |
||||
* Take FFT to convert to frequency domain |
||||
* Manipulate the frequency bins as desired (LP filter? BP filter? Formant shift?) |
||||
* Take IFFT to convert back to time domain |
||||
* Send samples back to the audio interface |
||||
* |
||||
* Assumes the use of the Audio library from PJRC |
||||
* |
||||
* Adapted to OpenAudio, "_OA". June 2020 Bob Larkin. |
||||
* This changed from direct F32 AudioInputI2S to I16 Teensy Audio Library |
||||
* versions with Chip Audette's AudioConvert objects. Also removed volume |
||||
* control. Class and file names are isolated from other libraries by "_OA". |
||||
* Tested T3.6 and T4.0 with PJRC Teensy Audio Adaptor. |
||||
*
|
||||
* Ref: https://github.com/Tympan/Tympan_Library
|
||||
* https://github.com/Tympan/Tympan_Library/tree/master/examples/04-FrequencyDomain/LowpassFilter_FD
|
||||
* https://forum.pjrc.com/threads/40188-Fast-Convolution-filtering-in-floating-point-with-Teensy-3-6
|
||||
* https://forum.pjrc.com/threads/40590-Teensy-Convolution-SDR-(Software-Defined-Radio)
|
||||
*
|
||||
* This example code is in the public domain (MIT License) |
||||
*/ |
||||
|
||||
#include "SD.h" |
||||
#include "AudioStream_F32.h" |
||||
#include <OpenAudio_ArduinoLibrary.h> |
||||
#include "AudioEffectLowpassFD_F32.h" // the local file holding your custom function |
||||
|
||||
//set the sample rate and block size
|
||||
const float sample_rate_Hz = 44117.f; |
||||
const int audio_block_samples = 128; // for freq domain processing, choose 16, 32, 64 or 128
|
||||
AudioSettings_F32 audio_settings(sample_rate_Hz, audio_block_samples); |
||||
|
||||
//create audio library objects for handling the audio
|
||||
AudioInputI2S i2sIn; |
||||
AudioConvert_I16toF32 cnvrt1; |
||||
AudioSynthWaveformSine_F32 sinewave(audio_settings); |
||||
AudioEffectLowpassFD_F32 audioEffectLowpassFD(audio_settings); //create the frequency-domain processing block
|
||||
AudioConvert_F32toI16 cnvrt2;
|
||||
AudioOutputI2S i2sOut; |
||||
AudioControlSGTL5000 codec; |
||||
//Make all of the audio connections if 1 for Codec input, 0 for internally generated sine wave
|
||||
#if 1 |
||||
AudioConnection patchCord1(i2sIn, 0, cnvrt1, 0); // connect to Left codec, 16-bit
|
||||
AudioConnection_F32 patchCord2(cnvrt1, 0, audioEffectLowpassFD, 0); // Now converted to float
|
||||
#else |
||||
AudioConnection_F32 patchCord1(sinewave, 0, audioEffectLowpassFD, 0); // connect sine to filter
|
||||
#endif |
||||
AudioConnection_F32 patchCord5(audioEffectLowpassFD, 0, cnvrt2, 0); // filtered output
|
||||
AudioConnection patchCord6(cnvrt2, 0, i2sOut, 0); // Left channel
|
||||
|
||||
int is_windowing_active = 0; |
||||
void setup() { |
||||
//begin the serial comms (for debugging), any baud rate
|
||||
Serial.begin(1); delay(500); |
||||
Serial.println("FrequencyDomainDemo2: starting setup()..."); |
||||
Serial.print(" : sample rate (Hz) = "); Serial.println(audio_settings.sample_rate_Hz); |
||||
Serial.print(" : block size (samples) = "); Serial.println(audio_settings.audio_block_samples); |
||||
|
||||
// Audio connections require memory to work. For more
|
||||
// detailed information, see the MemoryAndCpuUsage example
|
||||
AudioMemory(10); AudioMemory_F32(20, audio_settings); |
||||
|
||||
codec.enable(); |
||||
|
||||
// Configure the frequency-domain algorithm
|
||||
int N_FFT = 1024; |
||||
audioEffectLowpassFD.setup(audio_settings,N_FFT); //do after AudioMemory_F32();
|
||||
|
||||
sinewave.frequency(1000.0f); |
||||
sinewave.amplitude(0.025f); |
||||
|
||||
Serial.println("Setup complete."); |
||||
} |
||||
|
||||
void loop() { |
||||
|
||||
}
|
||||
|
||||
//This routine prints the current and maximum CPU usage and the current usage of the AudioMemory that has been allocated
|
||||
void printCPUandMemory(unsigned long curTime_millis, unsigned long updatePeriod_millis) { |
||||
//static unsigned long updatePeriod_millis = 3000; //how many milliseconds between updating gain reading?
|
||||
static unsigned long lastUpdate_millis = 0; |
||||
|
||||
//has enough time passed to update everything?
|
||||
if (curTime_millis < lastUpdate_millis) lastUpdate_millis = 0; //handle wrap-around of the clock
|
||||
if ((curTime_millis - lastUpdate_millis) > updatePeriod_millis) { //is it time to update the user interface?
|
||||
Serial.print("printCPUandMemory: "); |
||||
Serial.print("CPU Cur/Peak: "); |
||||
Serial.print(audio_settings.processorUsage()); |
||||
//Serial.print(AudioProcessorUsage()); //if not using AudioSettings_F32
|
||||
Serial.print("%/"); |
||||
Serial.print(audio_settings.processorUsageMax()); |
||||
//Serial.print(AudioProcessorUsageMax()); //if not using AudioSettings_F32
|
||||
Serial.print("%, "); |
||||
Serial.print("Dyn MEM Int16 Cur/Peak: "); |
||||
Serial.print(AudioMemoryUsage()); |
||||
Serial.print("/"); |
||||
Serial.print(AudioMemoryUsageMax()); |
||||
Serial.print(", "); |
||||
Serial.print("Dyn MEM Float32 Cur/Peak: "); |
||||
Serial.print(AudioMemoryUsage_F32()); |
||||
Serial.print("/"); |
||||
Serial.print(AudioMemoryUsageMax_F32()); |
||||
Serial.println(); |
||||
|
||||
lastUpdate_millis = curTime_millis; //we will use this value the next time around.
|
||||
} |
||||
} |
||||
Loading…
Reference in new issue