#ifndef __ardour_dB_h__
#define __ardour_dB_h__
+#include <limits>
#include "pbd/fastlog.h"
+#define GAIN_COEFF_ZERO 0.f
+#define GAIN_COEFF_SMALL 0.0000001f //-140dB
+#define GAIN_COEFF_UNITY 1.f
+
static inline float dB_to_coefficient (float dB) {
return dB > -318.8f ? pow (10.0f, dB * 0.05f) : 0.0f;
}
}
static inline float accurate_coefficient_to_dB (float coeff) {
- return 20.0f * log10 (coeff);
+ if (coeff < 1e-15) return -std::numeric_limits<float>::infinity();
+ return 20.0f * log10f (coeff);
+}
+
+static inline double dB_coeff_step(double max_coeff) {
+ const double max_db = lrint(accurate_coefficient_to_dB(max_coeff));
+ return 0.1 * (max_coeff / max_db);
}
-static const double zero_db_as_fraction = 0.781787;
+extern double zero_db_as_fraction;
#endif /* __ardour_dB_h__ */