Add a new option "loudness". When enabled, track_gain + normalisation… (#127)

* Add a new option "loudness". When enabled, track_gain + normalisationPregain will be applied to the incoming packet values. If disabled, incoming packet values will remain pristine.

* Refactored code

Author: leafy7382

core/src/main/java/xyz/gianlu/librespot/FileConfiguration.java

@@ -149,6 +149,11 @@ public boolean preloadEnabled() {
         return config.get("preload.enabled");
     }
 
+    @Override
+    public boolean enableNormalisation() {
+        return config.get("player.enableNormalisation");
+    }
+
     @Override
     public float normalisationPregain() {
         Object raw = config.get("player.normalisationPregain");

core/src/main/java/xyz/gianlu/librespot/player/Player.java

@@ -545,6 +545,8 @@ public interface Configuration {
 
         boolean preloadEnabled();
 
+        boolean enableNormalisation();
+
         float normalisationPregain();
 
         @Nullable

core/src/main/java/xyz/gianlu/librespot/player/codecs/Codec.java

@@ -35,8 +35,12 @@ public abstract class Codec implements Runnable {
         this.listener = listener;
         this.lines = lines;
         this.duration = duration;
-        this.normalizationFactor = normalizationData != null ? normalizationData.getFactor(conf) : 1;
         this.preloadEnabled = conf.preloadEnabled();
+
+        if (conf.enableNormalisation())
+            this.normalizationFactor = normalizationData != null ? normalizationData.getFactor(conf) : 1;
+        else
+            this.normalizationFactor = 1;
     }
 
     public final void play() {

core/src/main/resources/default.toml

@@ -23,6 +23,7 @@ enabled = true # Preload enabled
 [player] ### Player ###
 autoplayEnabled = true # Autoplay similar songs when your music ends
 preferredAudioQuality = "VORBIS_160" # Preferred audio quality (VORBIS_96, VORBIS_160, VORBIS_320)
+enableNormalisation = true # Whether to apply the Spotify loudness normalisation
 normalisationPregain = 0.0 # Normalisation pregain
 initialVolume = 65536 # Initial volume (0-65536)
 logAvailableMixers = true # Log available mixers
@@ -33,4 +34,4 @@ enableLoadingState = true # Enable loading state (useful for slow connections)
 useCdn = true # Use CDN to download tracks
 
 [player.episodes]
-useCdn = true # Use CDN to download episodes
+useCdn = true # Use CDN to download episodes