Add a final makeup gain, trying to set the level straight at +0 LU (more or less...

[nageru] / mixer.h

diff --git a/mixer.h b/mixer.h
index f50eb58db5560f620b2fcdb1cc9097f4b6c5d1cb..ffae67a6e398687640c155ae12d8dd81c33f11e0 100644 (file)
--- a/mixer.h
+++ b/mixer.h
@@ -103,7 +103,7 @@ public:
 
        typedef std::function<void(float level_lufs, float peak_db,
                                   float global_level_lufs, float range_low_lufs, float range_high_lufs,
-                                  float gain_staging_db)> audio_level_callback_t;
+                                  float gain_staging_db, float final_makeup_gain_db)> audio_level_callback_t;
        void set_audio_level_callback(audio_level_callback_t callback)
        {
                audio_level_callback = callback;
@@ -171,17 +171,30 @@ public:
 
        void set_gain_staging_db(float gain_db)
        {
-               std::unique_lock<std::mutex> lock(level_compressor_mutex);
+               std::unique_lock<std::mutex> lock(compressor_mutex);
                level_compressor_enabled = false;
                gain_staging_db = gain_db;
        }
 
        void set_gain_staging_auto(bool enabled)
        {
-               std::unique_lock<std::mutex> lock(level_compressor_mutex);
+               std::unique_lock<std::mutex> lock(compressor_mutex);
                level_compressor_enabled = enabled;
        }
 
+       void set_final_makeup_gain_db(float gain_db)
+       {
+               std::unique_lock<std::mutex> lock(compressor_mutex);
+               final_makeup_gain_auto = false;
+               final_makeup_gain = pow(10.0f, gain_db / 20.0f);
+       }
+
+       void set_final_makeup_gain_auto(bool enabled)
+       {
+               std::unique_lock<std::mutex> lock(compressor_mutex);
+               final_makeup_gain_auto = enabled;
+       }
+
        void schedule_cut()
        {
                should_cut = true;
@@ -283,12 +296,12 @@ private:
        std::atomic<float> locut_cutoff_hz;
 
        // First compressor; takes us up to about -12 dBFS.
-       std::mutex level_compressor_mutex;
        StereoCompressor level_compressor;  // Under compressor_mutex. Used to set/override gain_staging_db if <level_compressor_enabled>.
        float gain_staging_db = 0.0f;  // Under compressor_mutex.
        bool level_compressor_enabled = true;  // Under compressor_mutex.
 
-       static constexpr float ref_level_dbfs = -14.0f;
+       static constexpr float ref_level_dbfs = -14.0f;  // Chosen so that we end up around 0 LU in practice.
+       static constexpr float ref_level_lufs = -23.0f;  // 0 LU, more or less by definition.
 
        StereoCompressor limiter;
        std::atomic<float> limiter_threshold_dbfs{ref_level_dbfs + 4.0f};   // 4 dB.
@@ -297,6 +310,9 @@ private:
        std::atomic<float> compressor_threshold_dbfs{ref_level_dbfs - 12.0f};  // -12 dB.
        std::atomic<bool> compressor_enabled{true};
 
+       double final_makeup_gain = 1.0;  // Under compressor_mutex. Read/write by the user. Note: Not in dB, we want the numeric precision so that we can change it slowly.
+       bool final_makeup_gain_auto = true;  // Under compressor_mutex.
+
        std::unique_ptr<ALSAOutput> alsa;
 
        struct AudioTask {