Merge branch 'master' into windows

[ardour.git] / libs / ardour / pi_controller.cc

diff --git a/libs/ardour/pi_controller.cc b/libs/ardour/pi_controller.cc
index 2ecfe730d8cd117cffa2737d0aada32750dcd8f1..a165aa9e40d379bb3c8dff2a05c81e14163ef0f3 100644 (file)
--- a/libs/ardour/pi_controller.cc
+++ b/libs/ardour/pi_controller.cc
@@ -1,11 +1,11 @@
 /*
   Copyright (C) 2008 Torben Hohn
-  
+
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
-  
+
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
@@ -25,8 +25,8 @@
 static inline double hann(double x) {
        return 0.5 * (1.0 - cos(2 * M_PI * x));
 }
-    
-PIController::PIController (double resample_factor, int fir_size) 
+
+PIController::PIController (double resample_factor, int fir_size)
 {
        resample_mean = resample_factor;
        static_resample_factor = resample_factor;
@@ -35,12 +35,12 @@ PIController::PIController (double resample_factor, int fir_size)
        offset_differential_index = 0;
        offset_integral = 0.0;
        smooth_size = fir_size;
-        
+
        for (int i = 0; i < fir_size; i++) {
                 offset_array[i] = 0.0;
                 window_array[i] = hann(double(i) / (double(fir_size) - 1.0));
        }
-       
+
        // These values could be configurable
        catch_factor = 20000;
        catch_factor2 = 4000;
@@ -62,7 +62,7 @@ PIController::get_ratio (int fill_level, int period_size)
        double this_catch_factor = catch_factor;
        double this_catch_factor2 = catch_factor2 * 4096.0/(double)period_size;
 
-       
+
        // Save offset.
        if( fir_empty ) {
            for (int i = 0; i < smooth_size; i++) {
@@ -72,50 +72,50 @@ PIController::get_ratio (int fill_level, int period_size)
        } else {
            offset_array[(offset_differential_index++) % smooth_size] = offset;
        }
-        
+
        // Build the mean of the windowed offset array basically fir lowpassing.
        smooth_offset = 0.0;
        for (int i = 0; i < smooth_size; i++) {
                 smooth_offset += offset_array[(i + offset_differential_index - 1) % smooth_size] * window_array[i];
        }
        smooth_offset /= double(smooth_size);
-        
+
        // This is the integral of the smoothed_offset
        offset_integral += smooth_offset;
 
        std::cerr << smooth_offset << " ";
-       
+
        // Clamp offset : the smooth offset still contains unwanted noise which would go straigth onto the resample coeff.
        // It only used in the P component and the I component is used for the fine tuning anyways.
-    
+
        if (fabs(smooth_offset) < pclamp)
                 smooth_offset = 0.0;
-       
+
        smooth_offset += (static_resample_factor - resample_mean) * this_catch_factor;
-       
-       // Ok, now this is the PI controller. 
+
+       // Ok, now this is the PI controller.
        // u(t) = K * (e(t) + 1/T \int e(t') dt')
-       // Kp = 1/catch_factor and T = catch_factor2  Ki = Kp/T 
-       current_resample_factor 
+       // Kp = 1/catch_factor and T = catch_factor2  Ki = Kp/T
+       current_resample_factor
                 = static_resample_factor - smooth_offset / this_catch_factor - offset_integral / this_catch_factor / this_catch_factor2;
-       
+
        // Now quantize this value around resample_mean, so that the noise which is in the integral component doesnt hurt.
        current_resample_factor = floor((current_resample_factor - resample_mean) * controlquant + 0.5) / controlquant + resample_mean;
-       
+
        // Calculate resample_mean so we can init ourselves to saner values.
        // resample_mean = 0.9999 * resample_mean + 0.0001 * current_resample_factor;
        resample_mean = (1.0-0.01) * resample_mean + 0.01 * current_resample_factor;
        std::cerr << fill_level << " " << smooth_offset << " " << offset_integral << " " << current_resample_factor << " " << resample_mean << "\n";
        return current_resample_factor;
 }
-        
-void 
+
+void
 PIController::out_of_bounds()
 {
        int i;
        // Set the resample_rate... we need to adjust the offset integral, to do this.
        // first look at the PI controller, this code is just a special case, which should never execute once
-       // everything is swung in. 
+       // everything is swung in.
        offset_integral = - (resample_mean - static_resample_factor) * catch_factor * catch_factor2;
        // Also clear the array. we are beginning a new control cycle.
        for (i = 0; i < smooth_size; i++) {
@@ -157,7 +157,7 @@ PIChaser::get_ratio(framepos_t chasetime_measured, framepos_t chasetime, framepo
        feed_estimator( chasetime_measured, chasetime );
        std::cerr << (double)chasetime_measured/48000.0 << " " << chasetime << " " << slavetime << " ";
        double crude = get_estimate();
-       double fine;  
+       double fine;
        framepos_t massaged_chasetime = chasetime + (framepos_t)( (double)(slavetime_measured - chasetime_measured) * crude );
 
        fine = pic->get_ratio (slavetime - massaged_chasetime, period_size);
@@ -183,7 +183,7 @@ PIChaser::get_ratio(framepos_t chasetime_measured, framepos_t chasetime, framepo
            speed = crude;
            pic->reset( crude );
        }
-       
+
        return speed;
 }