Permit rational precision to vary by quality setting in RatioOftenChanging mode

src/common/BQResampler.cpp

@@ -122,6 +122,7 @@ BQResampler::QualityParams::QualityParams(Quality q)
         k_snr = 70.0;
         k_transition = 0.2;
         cut = 0.9;
+        rational_max = 48000;
         break;
     case FastestTolerable:
         p_multiple = 62;
@@ -129,6 +130,7 @@ BQResampler::QualityParams::QualityParams(Quality q)
         k_snr = 90.0;
         k_transition = 0.05;
         cut = 0.975;
+        rational_max = 96000;
         break;
     case Best:
         p_multiple = 122;
@@ -136,6 +138,7 @@ BQResampler::QualityParams::QualityParams(Quality q)
         k_snr = 100.0;
         k_transition = 0.01;
         cut = 0.995;
+        rational_max = 192000;
         break;
     }
 }
@@ -375,7 +378,7 @@ BQResampler::pick_params(double ratio) const
 {
     // Farey algorithm, see
     // https://www.johndcook.com/blog/2010/10/20/best-rational-approximation/
-    int max_denom = 192000;
+    int max_denom = m_qparams.rational_max;
     double a = 0.0, b = 1.0, c = 1.0, d = 0.0;
     double pa = a, pb = b, pc = c, pd = d;
     double eps = 1e-9;

src/common/BQResampler.h

@@ -71,6 +71,7 @@ private:
         double k_snr;
         double k_transition;
         double cut;
+        int rational_max;
         QualityParams(Quality);
     };