musicmuster/app/music.py
Keith Edmunds d2444159ac Improved fading
fade() takes an optional parameter, fade_seconds
fading is now logarithmic
2023-10-17 22:38:57 +01:00

146 lines
3.6 KiB
Python

# import os
import threading
import vlc # type: ignore
#
from config import Config
from helpers import file_is_unreadable
from typing import Optional
from time import sleep
from log import log
from PyQt6.QtCore import ( # type: ignore
QRunnable,
QThreadPool,
)
lock = threading.Lock()
class FadeTrack(QRunnable):
def __init__(self, player: vlc.MediaPlayer, fade_seconds) -> None:
super().__init__()
self.player = player
self.fade_seconds = fade_seconds
def run(self):
"""
Implementation of fading the player
"""
if not self.player:
return
# Reduce volume logarithmically
total_steps = self.fade_seconds * Config.FADEOUT_STEPS_PER_SECOND
db_reduction_per_step = Config.FADEOUT_DB / total_steps
reduction_factor_per_step = pow(10, (db_reduction_per_step / 20))
volume = self.player.audio_get_volume()
for i in range(1, total_steps + 1):
self.player.audio_set_volume(
int(volume * pow(reduction_factor_per_step, i))
)
sleep(1 / Config.FADEOUT_STEPS_PER_SECOND)
self.player.stop()
log.debug(f"Releasing player {self.player=}")
self.player.release()
class Music:
"""
Manage the playing of music tracks
"""
def __init__(self) -> None:
self.VLC = vlc.Instance()
self.player = None
self.max_volume = Config.VOLUME_VLC_DEFAULT
def fade(self, fade_seconds: int = Config.FADEOUT_SECONDS) -> None:
"""
Fade the currently playing track.
The actual management of fading runs in its own thread so as not
to hold up the UI during the fade.
"""
if not self.player:
return
if not self.player.get_position() > 0 and self.player.is_playing():
return
# Take a copy of current player to allow another track to be
# started without interfering here
with lock:
p = self.player
self.player = None
pool = QThreadPool.globalInstance()
fader = FadeTrack(p, fade_seconds=fade_seconds)
pool.start(fader)
def get_position(self) -> Optional[float]:
"""Return current position"""
if not self.player:
return None
return self.player.get_position()
def play(self, path: str, position: Optional[float] = None) -> Optional[int]:
"""
Start playing the track at path.
Log and return if path not found.
"""
if file_is_unreadable(path):
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.set_volume(self.max_volume)
if position:
self.player.set_position(position)
return status
def set_volume(self, volume=None, set_default=True):
"""Set maximum volume used for player"""
if not self.player:
return
if set_default:
self.max_volume = volume
if volume is None:
volume = Config.VOLUME_VLC_DEFAULT
self.player.audio_set_volume(volume)
def stop(self) -> float:
"""Immediately stop playing"""
if not self.player:
return 0.0
p = self.player
self.player = None
with lock:
position = p.get_position()
p.stop()
p.release()
p = None
return position