Add return type in music.py

fade() takes an optional parameter, fade_seconds
fading is now logarithmic

app/config.py

@@ -53,8 +53,9 @@ class Config(object):
     FADE_CURVE_BACKGROUND = "lightyellow"
     FADE_CURVE_FOREGROUND = "blue"
     FADE_CURVE_MS_BEFORE_FADE = 5000
-    FADE_STEPS = 20
+    FADEOUT_DB = -10
-    FADE_TIME = 3000
+    FADEOUT_SECONDS = 5
+    FADEOUT_STEPS_PER_SECOND = 5
     HIDE_AFTER_PLAYING_OFFSET = 5000
     INFO_TAB_TITLE_LENGTH = 15
     LAST_PLAYED_TODAY_STRING = "Today"

app/music.py

@@ -19,11 +19,12 @@ lock = threading.Lock()
 
 
 class FadeTrack(QRunnable):
-    def __init__(self, player: vlc.MediaPlayer) -> None:
+    def __init__(self, player: vlc.MediaPlayer, fade_seconds) -> None:
         super().__init__()
         self.player = player
+        self.fade_seconds = fade_seconds
 
-    def run(self):
+    def run(self) -> None:
         """
         Implementation of fading the player
         """
@@ -31,24 +32,18 @@ class FadeTrack(QRunnable):
         if not self.player:
             return
 
-        fade_time = Config.FADE_TIME / 1000
+        # Reduce volume logarithmically
-        steps = Config.FADE_STEPS
+        total_steps = self.fade_seconds * Config.FADEOUT_STEPS_PER_SECOND
-        sleep_time = fade_time / steps
+        db_reduction_per_step = Config.FADEOUT_DB / total_steps
-        original_volume = self.player.audio_get_volume()
+        reduction_factor_per_step = pow(10, (db_reduction_per_step / 20))
 
-        # We reduce volume by one mesure first, then by two measures,
+        volume = self.player.audio_get_volume()
-        # then three, and so on.
-        # The sum of the arithmetic sequence 1, 2, 3, ..n is
-        # (n**2 + n) / 2
-        total_measures_count = (steps**2 + steps) / 2
 
-        measures_to_reduce_by = 0
+        for i in range(1, total_steps + 1):
-
+            self.player.audio_set_volume(
-        for i in range(1, steps + 1):
+                int(volume * pow(reduction_factor_per_step, i))
-            measures_to_reduce_by += i
+            )
-            volume_factor = 1 - (measures_to_reduce_by / total_measures_count)
+            sleep(1 / Config.FADEOUT_STEPS_PER_SECOND)
-            self.player.audio_set_volume(int(original_volume * volume_factor))
-            sleep(sleep_time)
 
         self.player.stop()
         log.debug(f"Releasing player {self.player=}")
@@ -65,7 +60,7 @@ class Music:
         self.player = None
         self.max_volume = Config.VOLUME_VLC_DEFAULT
 
-    def fade(self) -> None:
+    def fade(self, fade_seconds: int = Config.FADEOUT_SECONDS) -> None:
         """
         Fade the currently playing track.
 
@@ -86,7 +81,7 @@ class Music:
             self.player = None
 
         pool = QThreadPool.globalInstance()
-        fader = FadeTrack(p)
+        fader = FadeTrack(p, fade_seconds=fade_seconds)
         pool.start(fader)
 
     def get_position(self) -> Optional[float]:
@@ -96,7 +91,7 @@ class Music:
             return None
         return self.player.get_position()
 
-    def play(self, path: str, position: Optional[float] = None) -> Optional[int]:
+    def play(self, path: str, position: Optional[float] = None) -> None:
         """
         Start playing the track at path.
 
@@ -107,19 +102,15 @@ class Music:
             log.error(f"play({path}): path not readable")
             return None
 
-        status = -1
-
         media = self.VLC.media_new_path(path)
         self.player = media.player_new_from_media()
         if self.player:
-            status = self.player.play()
+            _ = self.player.play()
             self.set_volume(self.max_volume)
             if position:
                 self.player.set_position(position)
 
-        return status
+    def set_volume(self, volume=None, set_default=True) -> None:
-
-    def set_volume(self, volume=None, set_default=True):
         """Set maximum volume used for player"""
 
         if not self.player: