Files

copied
Last update 5 years 8 months
Filesbraids
..
bootloader
data
drivers
hardware_design
resources
test
README.md
__init__.py
analog_oscillator.cc
analog_oscillator.h
braids.cc
digital_oscillator.cc
digital_oscillator.h
envelope.h
excitation.h
macro_oscillator.cc
macro_oscillator.h
makefile
parameter_interpolation.h
quantizer.cc
quantizer.h
quantizer_scales.h
resources.cc
resources.h
settings.cc
settings.h
signature_waveshaper.h
svf.h
ui.cc
ui.h
vco_jitter_source.h
quantizer.cc
// Copyright 2015 Olivier Gillet. // // Author: Olivier Gillet (ol.gillet@gmail.com) // // Permission is hereby granted, free of charge, to any person obtaining a copy // of this software and associated documentation files (the "Software"), to deal // in the Software without restriction, including without limitation the rights // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell // copies of the Software, and to permit persons to whom the Software is // furnished to do so, subject to the following conditions: // // The above copyright notice and this permission notice shall be included in // all copies or substantial portions of the Software. // // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN // THE SOFTWARE. // // See http://creativecommons.org/licenses/MIT/ for more information. // // ----------------------------------------------------------------------------- // // Note quantizer #include "braids/quantizer.h" #include <algorithm> #include <cstdlib> namespace braids { void Quantizer::Init() { enabled_ = true; codeword_ = 0; previous_boundary_ = 0; next_boundary_ = 0; for (int16_t i = 0; i < 128; ++i) { codebook_[i] = (i - 64) << 7; } } void Quantizer::Configure( const int16_t* notes, int16_t span, size_t num_notes) { enabled_ = notes != NULL && num_notes != 0 && span != 0; if (enabled_) { int32_t octave = 0; size_t note = 0; int16_t root = 0; for (int32_t i = 0; i < 64; ++i) { int32_t up = root + notes[note] + span * octave; int32_t down = root + notes[num_notes - 1 - note] + (-octave - 1) * span; CLIP(up) CLIP(down) codebook_[64 + i] = up; codebook_[64 - i - 1] = down; ++note; if (note >= num_notes) { note = 0; ++octave; } } } } int32_t Quantizer::Process(int32_t pitch, int32_t root) { if (!enabled_) { return pitch; } pitch -= root; if (pitch >= previous_boundary_ && pitch <= next_boundary_) { // We're still in the voronoi cell for the active codeword. pitch = codeword_; } else { // Search for the nearest neighbour in the codebook. int16_t upper_bound_index = std::upper_bound( &codebook_[3], &codebook_[126], static_cast<int16_t>(pitch)) - &codebook_[0]; int16_t lower_bound_index = upper_bound_index - 2; int16_t best_distance = 16384; int16_t q = -1; for (int16_t i = lower_bound_index; i <= upper_bound_index; ++i) { int16_t distance = abs(pitch - codebook_[i]); if (distance < best_distance) { best_distance = distance; q = i; } } codeword_ = codebook_[q]; // Enlarge the current voronoi cell a bit for hysteresis. previous_boundary_ = (9 * codebook_[q - 1] + 7 * codeword_) >> 4; next_boundary_ = (9 * codebook_[q + 1] + 7 * codeword_) >> 4; pitch = codeword_; } pitch += root; return pitch; } } // namespace braids
Report a bug