switching loudness and masking

cpp/zimt/fourier_bank.cc

@@ -52,15 +52,15 @@ float Loudness(int k, float val) {
     { 0.354, -3.5, 12.3, }, // 12500
   };
   const float *vals = &pars[k / 5][0];
-  static float constant1 = 33.13457678814273;
-  static float constant2 = 27.720606627666342;
+  static float constant1 = 32.617115877848235;
+  static float constant2 = 27.588336629470223;
   val *= (constant1 + vals[1]) * (1.0 / constant2);
   return val;
 }
 
 float SimpleDb(float energy) {
   // ideally 78.3 db
-  static const float full_scale_sine_db = 77.47500423191678;
+  static const float full_scale_sine_db = 77.4742570462833;
   static const float exp_full_scale_sine_db = exp(full_scale_sine_db);
   // epsilon, but the biggest one you saw (~4.95e23)
   static const float epsilon = 1.0033294789821357e-09 * exp_full_scale_sine_db;
@@ -71,33 +71,49 @@ float SimpleDb(float energy) {
 
 void FinalizeDb(hwy::AlignedNDArray<float, 2>& channels, float mul,
                 size_t out_ix) {
+  for (int k = 0; k < kNumRotators; ++k) {
+    float v = SimpleDb(mul * channels[{out_ix}][k]);
+    channels[{out_ix}][k] = Loudness(k, v);
+  }
   double masker = 0.0;
   static const double octaves_in_20_to_20000 = log(20000/20.)/log(2);
   static const double octaves_per_rot =
       octaves_in_20_to_20000 / float(kNumRotators - 1);
-  static const double masker_step_per_octave_up_0 = 15.795427054351489;
-  static const double masker_step_per_octave_up_1 = 21.852019717473834;
-  static const double masker_step_per_octave_up_2 = 20.79201971747383;
+  static const double masker_step_per_octave_up_0 = 14.713710868625487;
+  static const double masker_step_per_octave_up_1 = 21.82837106569622;
+  static const double masker_step_per_octave_up_2 = 6.398379411619291;
   static const double masker_step_per_rot_up_0 = octaves_per_rot * masker_step_per_octave_up_0;
   static const double masker_step_per_rot_up_1 = octaves_per_rot * masker_step_per_octave_up_1;
   static const double masker_step_per_rot_up_2 = octaves_per_rot * masker_step_per_octave_up_2;
-  static const double masker_gap_up = 19.140338374861235;
-  static const float maskingStrengthUp = 0.1252262923615547;
+  static const double masker_gap_up = 20.73060456058724;
+  static const float maskingStrengthUp = 0.13574932102981796;
   static const float up_blur = 0.8738593591692092;
-  static const float fraction_up = 1.02;
+  static const float fraction_up = 1.0189925926484509;
 
-  static const double masker_step_per_octave_down = 42.33972783112732;
+  static const double masker_step_per_octave_down = 53.404905982421795;
   static const double masker_step_per_rot_down = octaves_per_rot * masker_step_per_octave_down;
-  static const double masker_gap_down = 19.66099875393617;
-  static const float maskingStrengthDown = 0.19329999999999992;
+  static const double masker_gap_down = 18.944464865908305;
+  static const float maskingStrengthDown = 0.18023700284914426;
   static const float down_blur = 0.714425315233319;
 
   static const float min_limit = -11.397341001787765;
-  static const float fraction_down = 1.02;
+  static const float fraction_down = 1.0198983999315951;
+
+  static const float temporal0 = 0.0999047126828788;
+  static const float temporal1 = 0.08127754119644388;
+  static const float temporal2 = 0.009595578765516729;
+  static float weightp = 0.17921002086852425;
+  static float weightm = 0.04999327787335808;
+
+  static float mask_k = 0.017060747885286255;
+
   // Scan frequencies from bottom to top, let lower frequencies to mask higher frequencies.
   // 'masker' maintains the masking envelope from one bin to next.
   for (int k = 0; k < kNumRotators; ++k) {
-    float v = SimpleDb(mul * channels[{out_ix}][k]);
+    float v = channels[{out_ix}][k];
+    if (out_ix != 0) {
+      v = (1.0 - mask_k) * v + mask_k * channels[{out_ix - 1}][k];
+    }
     if (v < min_limit) {
       v = min_limit;
     }
@@ -126,6 +142,9 @@ void FinalizeDb(hwy::AlignedNDArray<float, 2>& channels, float mul,
   masker = 0.0;
   for (int k = kNumRotators - 1; k >= 0; --k) {
     float v = channels[{out_ix}][k];
+    if (out_ix != 0) {
+      v = (1.0 - mask_k) * v + mask_k * channels[{out_ix - 1}][k];
+    }
     float v2 = (1 - down_blur) * v2 + down_blur * v;
     if (k == kNumRotators - 1) {
       v2 = v;
@@ -140,12 +159,19 @@ void FinalizeDb(hwy::AlignedNDArray<float, 2>& channels, float mul,
     channels[{out_ix}][k] = v;
     masker -= masker_step_per_rot_down;
   }
-  for (int k = 0; k < kNumRotators; ++k) {
-    channels[{out_ix}][k] = Loudness(k, channels[{out_ix}][k]);
-  }
   // temporal masker
   if (out_ix >= 3) {
     for (int k = 0; k < kNumRotators; ++k) {
+      float m = (temporal0 * channels[{out_ix - 1}][k] +
+                 temporal1 * channels[{out_ix - 2}][k] +
+                 temporal2 * channels[{out_ix - 3}][k]) / (temporal0 + temporal1 + temporal2);
+      if (m > channels[{out_ix}][k]) {
+        channels[{out_ix}][k] -= weightp * (m - channels[{out_ix}][k]);
+      } else {
+        channels[{out_ix}][k] -= weightm * (m - channels[{out_ix}][k]);
+      }
+      /*
+      // todo(jyrki): explore with this
       static const float temporal_masker0 = 0.1387454636244773;
       channels[{out_ix}][k] -=
           temporal_masker0 * (channels[{out_ix - 1}][k] - channels[{out_ix}][k]);
@@ -155,6 +181,7 @@ void FinalizeDb(hwy::AlignedNDArray<float, 2>& channels, float mul,
       static const float temporal_masker2 = -0.03785233735225447;
       channels[{out_ix}][k] -=
           temporal_masker2 * (channels[{out_ix - 3}][k] - channels[{out_ix}][k]);
+      */
     }
   }
 }