1 // Copyright 2015 Olivier Gillet. 2 // Copyright 2016 Matthias Puech. 3 // 4 // Author: Olivier Gillet (ol.gillet@gmail.com) 5 // Modified by: Matthias Puech (matthias.puech@gmail.com) 6 // 7 // Permission is hereby granted, free of charge, to any person obtaining a copy 8 // of this software and associated documentation files (the "Software"), to deal 9 // in the Software without restriction, including without limitation the rights 10 // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 11 // copies of the Software, and to permit persons to whom the Software is 12 // furnished to do so, subject to the following conditions: 13 // 14 // The above copyright notice and this permission notice shall be included in 15 // all copies or substantial portions of the Software. 16 // 17 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 18 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 19 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 20 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 21 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 22 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 23 // THE SOFTWARE. 24 // 25 // See http://creativecommons.org/licenses/MIT/ for more information. 26 // 27 // ----------------------------------------------------------------------------- 28 // 29 // Dynamic Gate 30 31 #ifndef GATE_H_ 32 #define GATE_H_ 33 34 #include "stmlib/dsp/dsp.h" 35 36 #include "parameters.h" 37 38 const float kThresholdLow = 0.002f * 32768.0f; 39 const float kThresholdHigh = 0.05f * 32768.0f; 40 41 class Gate { 42 public: Gate()43 Gate() { } ~Gate()44 ~Gate() { } 45 Init()46 void Init() { 47 peak_ = 0.5f; 48 } 49 Process(ShortFrame * in_out)50 inline void Process(ShortFrame* in_out) { 51 size_t size = kBlockSize; 52 while (size--) { 53 short l = (*in_out).l; 54 short r = (*in_out).r; 55 SLOPE(peak_, fabs(l), 0.05f, 0.00003f); 56 float gain = peak_ < kThresholdLow ? 0.0f : 57 peak_ > kThresholdHigh ? 1.0f : 58 (peak_ - kThresholdLow) / (kThresholdHigh - kThresholdLow); 59 (*in_out).l = l * gain; 60 (*in_out).r = r * gain; 61 ++in_out; 62 } 63 } 64 65 private: 66 float peak_; 67 68 DISALLOW_COPY_AND_ASSIGN(Gate); 69 }; 70 71 #endif 72