helpers/music_file.py

   1 import threading
   2 import pydub
   3 import time
   4 from transitions.extensions import HierarchicalMachine as Machine
   5
   6 import os.path
   7
   8 import audioop
   9
  10 from .lock import Lock
  11 from . import Config, gain, debug_print, error_print
  12 from .mixer import Mixer
  13 from .music_effect import GainEffect
  14
  15 file_lock = Lock("file")
  16
  17 class MusicFile:
  18     STATES = [
  19         'initial',
  20         'loading',
  21         'failed',
  22         {
  23             'name': 'loaded',
  24             'children': [
  25                 'playing',
  26                 'paused',
  27                 'stopping'
  28             ]
  29         }
  30     ]
  31     TRANSITIONS = [
  32         {
  33             'trigger': 'load',
  34             'source': 'initial',
  35             'dest': 'loading',
  36             'after': 'poll_loaded'
  37         },
  38         {
  39             'trigger': 'fail',
  40             'source': 'loading',
  41             'dest': 'failed'
  42         },
  43         {
  44             'trigger': 'success',
  45             'source': 'loading',
  46             'dest': 'loaded'
  47         },
  48         {
  49             'trigger': 'start_playing',
  50             'source': 'loaded',
  51             'dest': 'loaded_playing',
  52             # if a child has no transitions, then it is bubbled to the parent,
  53             # and we don't want that. Not useful in that machine precisely.
  54             'conditions': ['is_loaded']
  55         },
  56         {
  57             'trigger': 'pause',
  58             'source': 'loaded_playing',
  59             'dest': 'loaded_paused'
  60         },
  61         {
  62             'trigger': 'unpause',
  63             'source': 'loaded_paused',
  64             'dest': 'loaded_playing'
  65         },
  66         {
  67             'trigger': 'stop_playing',
  68             'source': ['loaded_playing','loaded_paused'],
  69             'dest': 'loaded_stopping'
  70         },
  71         {
  72             'trigger': 'stopped',
  73             'source': '*',
  74             'dest': 'loaded',
  75             'before': 'trigger_stopped_events',
  76             'conditions': ['is_in_use']
  77         }
  78     ]
  79
  80     def __init__(self, filename, mapping, name=None, gain=1):
  81         Machine(model=self, states=self.STATES,
  82                 transitions=self.TRANSITIONS, initial='initial',
  83                 ignore_invalid_triggers=True)
  84
  85         self.loaded_callbacks = []
  86         self.mapping = mapping
  87         self.filename = filename
  88         self.name = name or filename
  89         self.audio_segment = None
  90         self.initial_volume_factor = gain
  91         self.music_lock = Lock("music__" + filename)
  92
  93         threading.Thread(name="MSMusicLoad", target=self.load).start()
  94
  95     def reload_properties(self, name=None, gain=1):
  96         self.name = name or self.filename
  97         if gain != self.initial_volume_factor:
  98             self.initial_volume_factor = gain
  99             self.reload_music_file()
 100
 101     def reload_music_file(self):
 102         with file_lock:
 103             try:
 104                 if self.filename.startswith("/"):
 105                     filename = self.filename
 106                 else:
 107                     filename = Config.music_path + self.filename
 108
 109                 debug_print("Reloading « {} »".format(self.name))
 110                 initial_db_gain = gain(self.initial_volume_factor * 100)
 111                 self.audio_segment = pydub.AudioSegment \
 112                         .from_file(filename) \
 113                         .set_frame_rate(Config.frame_rate) \
 114                         .set_channels(Config.channels) \
 115                         .set_sample_width(Config.sample_width) \
 116                         .apply_gain(initial_db_gain)
 117             except Exception as e:
 118                 error_print("failed to reload « {} »: {}"\
 119                         .format(self.name, e))
 120                 self.loading_error = e
 121                 self.to_failed()
 122             else:
 123                 debug_print("Reloaded « {} »".format(self.name))
 124
 125     # Machine related events
 126     def on_enter_loading(self):
 127         with file_lock:
 128             try:
 129                 if self.filename.startswith("/"):
 130                     filename = self.filename
 131                 else:
 132                     filename = Config.music_path + self.filename
 133
 134                 debug_print("Loading « {} »".format(self.name))
 135                 self.mixer = self.mapping.mixer or Mixer()
 136                 initial_db_gain = gain(self.initial_volume_factor * 100)
 137                 self.audio_segment = pydub.AudioSegment \
 138                         .from_file(filename) \
 139                         .set_frame_rate(Config.frame_rate) \
 140                         .set_channels(Config.channels) \
 141                         .set_sample_width(Config.sample_width) \
 142                         .apply_gain(initial_db_gain)
 143                 self.sound_duration = self.audio_segment.duration_seconds
 144             except Exception as e:
 145                 error_print("failed to load « {} »: {}".format(self.name, e))
 146                 self.loading_error = e
 147                 self.fail()
 148             else:
 149                 self.success()
 150                 debug_print("Loaded « {} »".format(self.name))
 151
 152     def on_enter_loaded(self):
 153         self.cleanup()
 154
 155     def cleanup(self):
 156         self.gain_effects = []
 157         self.set_gain(0, absolute=True)
 158         self.current_audio_segment = None
 159         self.volume = 100
 160         self.wait_event = threading.Event()
 161         self.current_loop = 0
 162
 163     def on_enter_loaded_playing(self):
 164         self.mixer.add_file(self)
 165
 166     # Machine related states
 167     def is_in_use(self):
 168         return self.is_loaded(allow_substates=True) and not self.is_loaded()
 169
 170     def is_in_use_not_stopping(self):
 171         return self.is_loaded_playing() or self.is_loaded_paused()
 172
 173     # Machine related triggers
 174     def trigger_stopped_events(self):
 175         self.mixer.remove_file(self)
 176         self.wait_event.set()
 177         self.cleanup()
 178
 179     # Actions and properties called externally
 180     @property
 181     def sound_position(self):
 182         if self.is_in_use():
 183             return self.current_frame / self.current_audio_segment.frame_rate
 184         else:
 185             return 0
 186
 187     def play(self, fade_in=0, volume=100, loop=0, start_at=0):
 188         self.set_gain(gain(volume) + self.mapping.master_gain, absolute=True)
 189         self.volume = volume
 190         if loop < 0:
 191             self.last_loop = float('inf')
 192         else:
 193             self.last_loop = loop
 194
 195         with self.music_lock:
 196             self.current_audio_segment = self.audio_segment
 197             self.current_frame = int(start_at * self.audio_segment.frame_rate)
 198
 199         self.start_playing()
 200
 201         if fade_in > 0:
 202             db_gain = gain(self.volume, 0)[0]
 203             self.set_gain(-db_gain)
 204             self.add_fade_effect(db_gain, fade_in)
 205
 206     def seek(self, value=0, delta=False):
 207         if not self.is_in_use_not_stopping():
 208             return
 209
 210         with self.music_lock:
 211             self.abandon_all_effects()
 212             if delta:
 213                 frame_count = int(self.audio_segment.frame_count())
 214                 frame_diff = int(value * self.audio_segment.frame_rate)
 215                 self.current_frame += frame_diff
 216                 while self.current_frame < 0:
 217                     self.current_loop -= 1
 218                     self.current_frame += frame_count
 219                 while self.current_frame > frame_count:
 220                     self.current_loop += 1
 221                     self.current_frame -= frame_count
 222                 if self.current_loop < 0:
 223                     self.current_loop = 0
 224                     self.current_frame = 0
 225                 if self.current_loop > self.last_loop:
 226                     self.current_loop = self.last_loop
 227                     self.current_frame = frame_count
 228             else:
 229                 self.current_frame = max(
 230                         0,
 231                         int(value * self.audio_segment.frame_rate))
 232
 233     def stop(self, fade_out=0, wait=False, set_wait_id=None):
 234         if self.is_loaded_playing():
 235             ms = int(self.sound_position * 1000)
 236             ms_fo = max(1, int(fade_out * 1000))
 237
 238             new_audio_segment = self.current_audio_segment[: ms+ms_fo] \
 239                 .fade_out(ms_fo)
 240             with self.music_lock:
 241                 self.current_audio_segment = new_audio_segment
 242             self.stop_playing()
 243             if wait:
 244                 if set_wait_id is not None:
 245                     self.mapping.add_wait_id(set_wait_id, self.wait_event)
 246                 self.wait_end()
 247         else:
 248             self.stopped()
 249
 250     def abandon_all_effects(self):
 251         db_gain = 0
 252         for gain_effect in self.gain_effects:
 253             db_gain += gain_effect.get_last_gain()
 254
 255         self.gain_effects = []
 256         self.set_gain(db_gain)
 257
 258     def set_volume(self, value, delta=False, fade=0):
 259         [db_gain, self.volume] = gain(
 260                 value + int(delta) * self.volume,
 261                 self.volume)
 262
 263         self.set_gain_with_effect(db_gain, fade=fade)
 264
 265     def set_gain_with_effect(self, db_gain, fade=0):
 266         if not self.is_in_use():
 267             return
 268
 269         if fade > 0:
 270             self.add_fade_effect(db_gain, fade)
 271         else:
 272             self.set_gain(db_gain)
 273
 274     def wait_end(self):
 275         self.wait_event.clear()
 276         self.wait_event.wait()
 277
 278     # Let other subscribe for an event when they are ready
 279     def subscribe_loaded(self, callback):
 280         # FIXME: should lock to be sure we have no race, but it makes the
 281         # initialization screen not showing until everything is loaded
 282         if self.is_loaded(allow_substates=True):
 283             callback(True)
 284         elif self.is_failed():
 285             callback(False)
 286         else:
 287             self.loaded_callbacks.append(callback)
 288
 289     def poll_loaded(self):
 290         for callback in self.loaded_callbacks:
 291             callback(self.is_loaded())
 292         self.loaded_callbacks = []
 293
 294     # Callbacks
 295     def finished_callback(self):
 296         self.stopped()
 297
 298     def play_callback(self, out_data_length, frame_count):
 299         if self.is_loaded_paused():
 300             return b'\0' * out_data_length
 301
 302         with self.music_lock:
 303             [data, nb_frames] = self.get_next_sample(frame_count)
 304             if nb_frames < frame_count:
 305                 if self.is_loaded_playing() and\
 306                         self.current_loop < self.last_loop:
 307                     self.current_loop += 1
 308                     self.current_frame = 0
 309                     [new_data, new_nb_frames] = self.get_next_sample(
 310                             frame_count - nb_frames)
 311                     data += new_data
 312                     nb_frames += new_nb_frames
 313                 elif nb_frames == 0:
 314                     # FIXME: too slow when mixing multiple streams
 315                     threading.Thread(
 316                             name="MSFinishedCallback",
 317                             target=self.finished_callback).start()
 318
 319             return data.ljust(out_data_length, b'\0')
 320
 321     # Helpers
 322     def set_gain(self, db_gain, absolute=False):
 323         if absolute:
 324             self.db_gain = db_gain
 325         else:
 326             self.db_gain += db_gain
 327
 328     def get_next_sample(self, frame_count):
 329         fw = self.audio_segment.frame_width
 330
 331         data = b""
 332         nb_frames = 0
 333
 334         segment = self.current_audio_segment
 335         max_val = int(segment.frame_count())
 336
 337         start_i = max(self.current_frame, 0)
 338         end_i   = min(self.current_frame + frame_count, max_val)
 339         data += segment._data[start_i*fw : end_i*fw]
 340         nb_frames += end_i - start_i
 341         self.current_frame += end_i - start_i
 342
 343         volume_factor = self.volume_factor(self.effects_next_gain(nb_frames))
 344
 345         data = audioop.mul(data, Config.sample_width, volume_factor)
 346
 347         return [data, nb_frames]
 348
 349     def add_fade_effect(self, db_gain, fade_duration):
 350         if not self.is_in_use():
 351             return
 352
 353         self.gain_effects.append(GainEffect(
 354             "fade",
 355             self.current_audio_segment,
 356             self.current_loop,
 357             self.sound_position,
 358             self.sound_position + fade_duration,
 359             gain=db_gain))
 360
 361     def effects_next_gain(self, frame_count):
 362         db_gain = 0
 363         for gain_effect in self.gain_effects:
 364             [new_gain, last_gain] = gain_effect.get_next_gain(
 365                     self.current_frame,
 366                     self.current_loop,
 367                     frame_count)
 368             if last_gain:
 369                 self.set_gain(new_gain)
 370                 self.gain_effects.remove(gain_effect)
 371             else:
 372                 db_gain += new_gain
 373         return db_gain
 374
 375
 376     def volume_factor(self, additional_gain=0):
 377         return 10 ** ( (self.db_gain + additional_gain) / 20)
 378