#include "Shifter.h" #include #include // #define SAMPLE_BY_SAMPLE #ifndef PI_F #define PI_F 3.1415927410125732421875f #endif void Shifter::SetAutoTuneSpeed(float val) { out_midi_smoother.SetTimeConstant(val); } void Shifter::SetAutoTuneDepth(float val) { out_midi_smoother.SetDepth(val); } static inline float mtof(float m) { return powf(2, (m - 69.0f) / 12.0f) * 440.0f; } static inline bool float_equal(float one, float two) { return abs(one - two) < 1e-5f; } void Shifter::Init(float samplerate, int samplesPerBlock) { sample_rate_ = samplerate; blocksize = samplesPerBlock; out_midi_smoother.SetFrameTime((float)samplesPerBlock / samplerate); volume = 1; helm.setframesize(1024); helm.setoverlap(1); for (int i = 0; i < MAX_VOICES; ++i) { voices[i].Init(samplerate); } for (int i = 0; i < BUFFER_SIZE; ++i) { in_buffer[i] = 0; out_buffer[0][i] = 0; out_buffer[1][i] = 0; } for (int i = 0; i < 8192; ++i) { cos_lookup[i] = cos(2 * PI_F * i / 8192.0); } } void Shifter::Process(const float* const* in, float** out, size_t size) { DetectPitch(in, out, size); SetRates(); // for (size_t i = 0; i < size; ++i) { // out[0][i] = 0; // } GetSamples(out, in[0], size); //for (size_t i = 0; i < size; ++i) //{ // // out[0][i] = osc.Process(); // // out[0][i] = in[0][i]; // //out[0][i] = out[0][i] + in[0][i]; // out[1][i] = out[0][i]; //} // } } float findMedian(float a, float b, float c) { if ((a >= b && a <= c) || (a <= b && a >= c)) return a; else if ((b >= a && b <= c) || (b <= a && b >= c)) return b; else return c; } void Shifter::DetectPitch(const float* const* in, float** out, size_t size) { // detect current pitch // pitch_detect.update(in[0], size); // if(pitch_detect.available()) // { // float read = pitch_detect.read(); // if(read >= 35 && read <= 2000) // { // for(int i = 2; i > 0; --i){ // last_freqs[i] = last_freqs[i-1]; // } // last_freqs[0] = read; // } // } // current_pitch = findMedian(last_freqs[0], last_freqs[1], last_freqs[2]); // in_period = 1.0 / current_pitch * 48000; helm.iosamples(in[0], out[0], size); float period = helm.getperiod(); float fidel = helm.getfidelity(); //DBG("frequency: " << 48000 / period << " fidel: " << fidel); // Adjustable filter amount (0.0f = no filtering, 1.0f = max filtering) static float in_period_filter_amount = 0.5f; // You can expose this as a parameter if (fidel > 0.95) { // Smoothly filter in_period changes in_period = in_period * in_period_filter_amount + period * (1.0f - in_period_filter_amount); } float in_freq = sample_rate_ / in_period; float midi = (12 * log2f(in_freq / 440) + 69.0f); //target_out_period = in_period * out_period_filter_amount + target_out_period * (1 - out_period_filter_amount); out_midi = out_midi_smoother.update(midi, (int)(midi+.5)); out_period = sample_rate_ / mtof(out_midi); } void Shifter::SetRates() {} float Shifter::GetOutputEnvelopePeriod(int out_voice) { if (out_voice >= MAX_VOICES) { return in_period * formant_preserve + out_period *(1.0 - formant_preserve); } //TODO add something so that low pitch ratios end up reducing formant_preservation return in_period * formant_preserve + voices[out_voice].CurrentPeriod() * (1.0 - formant_preserve); } int Shifter::GetPeakIndex() { int index = in_playhead - in_period * 2; if (index < 0) index += BUFFER_SIZE; //search for max absolute value int max_index = -1; float max_value = -2; for (int j = 0; j < in_period; ++j) { //float val = fabs(in_buffer[index]); float val = in_buffer[index]; if (val > max_value) { max_index = index; max_value = val; } if (++index >= BUFFER_SIZE) { index -= BUFFER_SIZE; } } return max_index; } //void Shifter::AddInterpolatedFrame(int voice, int max_index, float resampling_period) { // float period_ratio = resampling_period / out_periods[voice]; // float f_index; // f_index = max_index - resampling_period; // if (f_index < 0) // { // f_index += BUFFER_SIZE; // } // float mult = 0; // int out_index = out_playhead; // for (int j = 0; j < resampling_period * 2; ++j) // { // // mult = .5 // // * (1 - cosf(2 * PI_F * j / (period_to_use * 2 - 1))); // float interp = f_index - (int)f_index; // mult = .5 // * (1 - cos_lookup[(int)((float)j / (resampling_period * 2.0) * 8191.0)]); // float value = ((1 - interp) * in_buffer[(int)f_index] + (interp)*in_buffer[(int)(f_index + 1) % 8192]) * mult; // out_buffer[0][out_index] += value * (1 - out_panning[voice]); // out_buffer[1][out_index] += value * out_panning[voice]; // // // f_index += period_ratio; // if (f_index >= BUFFER_SIZE) // { // f_index -= BUFFER_SIZE; // } // if (++out_index >= BUFFER_SIZE) // { // out_index -= BUFFER_SIZE; // } // } //} void Shifter::AddInterpolatedFrame(int voice, int max_index, float resampling_period) { float period_ratio = in_period / resampling_period; float f_index; f_index = max_index - in_period; if (f_index < 0) { f_index += BUFFER_SIZE; } float mult = 0; int out_index = out_playhead; for (int j = 0; j < resampling_period * 2; ++j) { // mult = .5 // * (1 - cosf(2 * PI_F * j / (period_to_use * 2 - 1))); float interp = f_index - (int)f_index; mult = .5 * (1 - cos_lookup[(int)((float)j / (resampling_period * 2.0) * 8191.0)]); float value = ((1 - interp) * in_buffer[(int)f_index] + (interp)*in_buffer[(int)(f_index + 1) % 8192]) * mult; if(voice >= MAX_VOICES) { //value *= volume; out_buffer[0][out_index] += value * melody_mix; out_buffer[1][out_index] += value * melody_mix; } else { value *= voices[voice].CurrentAmplitude() * volume; out_buffer[0][out_index] += value * voices[voice].GetPanning(0) * harmony_mix; out_buffer[1][out_index] += value * voices[voice].GetPanning(1) * harmony_mix; } f_index += period_ratio; if (f_index >= BUFFER_SIZE) { f_index -= BUFFER_SIZE; } if (++out_index >= BUFFER_SIZE) { out_index -= BUFFER_SIZE; } } } void Shifter::GetSamples(float** output, const float* input, size_t size) { for (int i = 0; i < size; ++i) { //add new samples if necessary for (int out_p = 0; out_p < MAX_VOICES; ++out_p) { voices[out_p].Process(); if (!voices[out_p].IsActive()) continue; if (voices[out_p].PeriodOverflow()) { float resampling_period = GetOutputEnvelopePeriod(out_p); //find the start index int max_index = GetPeakIndex(); //add samples centered on that max AddInterpolatedFrame(out_p, max_index, resampling_period); } } if (out_period_counter > out_period) { out_period_counter -= out_period; float resampling_period = GetOutputEnvelopePeriod(MAX_VOICES); //find the start index int max_index = GetPeakIndex(); //add samples centered on that max AddInterpolatedFrame(MAX_VOICES, max_index, resampling_period); } //add input samples in_buffer[in_playhead] = input[i]; //output samples, set to 0 for (int ch = 0; ch < 2; ++ch) { output[ch][i] = out_buffer[ch][out_playhead]; out_buffer[ch][out_playhead] = 0; } //increment playheads if (++in_playhead >= BUFFER_SIZE) { in_playhead -= BUFFER_SIZE; } if (++out_playhead >= BUFFER_SIZE) { out_playhead -= BUFFER_SIZE; } out_period_counter++; } } void Shifter::AddMidiNote(int note) { for (int i = 0; i < MAX_VOICES; ++i) { if (voices[i].onoff_ && voices[i].GetMidiNote() == note) { voices[i].Release(); } } for (int i = 0; i < MAX_VOICES; ++i) { if (!voices[i].onoff_) { voices[i].Trigger(note); return; } } } void Shifter::RemoveMidiNote(int note) { for (int i = 0; i < MAX_VOICES; ++i) { if (voices[i].GetMidiNote() == note) { voices[i].Release(); } } } void Shifter::SetHarmonyMix(float mix) { if (mix < .5) { melody_mix = 1.0f; harmony_mix = mix * 2.0f; } else { harmony_mix = 1.0f; melody_mix = (1.0f - mix) * 2.0f; } }