music_sampler/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 .helpers 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                 'stopped',
  26                 'playing',
  27                 'paused',
  28                 'stopping'
  29             ]
  30         }
  31     ]
  32     TRANSITIONS = [
  33         {
  34             'trigger': 'load',
  35             'source': ['initial', 'failed'],
  36             'dest': 'loading'
  37         },
  38         {
  39             'trigger': 'fail',
  40             'source': 'loading',
  41             'dest': 'failed'
  42         },
  43         {
  44             'trigger': 'unload',
  45             'source': ['failed', 'loaded_stopped'],
  46             'dest': 'initial',
  47         },
  48         {
  49             'trigger': 'success',
  50             'source': 'loading',
  51             'dest': 'loaded_stopped'
  52         },
  53         {
  54             'trigger': 'start_playing',
  55             'source': 'loaded_stopped',
  56             'dest': 'loaded_playing'
  57         },
  58         {
  59             'trigger': 'pause',
  60             'source': 'loaded_playing',
  61             'dest': 'loaded_paused'
  62         },
  63         {
  64             'trigger': 'unpause',
  65             'source': 'loaded_paused',
  66             'dest': 'loaded_playing'
  67         },
  68         {
  69             'trigger': 'stop_playing',
  70             'source': ['loaded_playing','loaded_paused'],
  71             'dest': 'loaded_stopping'
  72         },
  73         {
  74             'trigger': 'stopped',
  75             'source': 'loaded',
  76             'dest': 'loaded_stopped',
  77             'before': 'trigger_stopped_events',
  78             'unless': 'is_loaded_stopped',
  79         }
  80     ]
  81
  82     def __init__(self, filename, mapping, name=None, gain=1):
  83         machine = Machine(model=self, states=self.STATES,
  84                 transitions=self.TRANSITIONS, initial='initial',
  85                 auto_transitions=False,
  86                 after_state_change=self.notify_state_change)
  87
  88         self.state_change_callbacks = []
  89         self.mapping = mapping
  90         self.filename = filename
  91         self.name = name or filename
  92         self.audio_segment = None
  93         self.initial_volume_factor = gain
  94         self.music_lock = Lock("music__" + filename)
  95
  96         if Config.load_all_musics:
  97             threading.Thread(name="MSMusicLoad", target=self.load).start()
  98
  99     def reload_properties(self, name=None, gain=1):
 100         self.name = name or self.filename
 101         if gain != self.initial_volume_factor:
 102             self.initial_volume_factor = gain
 103             self.stopped()
 104             self.unload()
 105             self.load(reloading=True)
 106
 107     # Machine related events
 108     def on_enter_initial(self):
 109         self.audio_segment = None
 110
 111     def on_enter_loading(self, reloading=False):
 112         if reloading:
 113             prefix = 'Rel'
 114             prefix_s = 'rel'
 115         else:
 116             prefix = 'L'
 117             prefix_s = 'l'
 118
 119         with file_lock:
 120             if self.mapping.is_leaving_application:
 121                 self.fail()
 122                 return
 123
 124             try:
 125                 if self.filename.startswith("/"):
 126                     filename = self.filename
 127                 else:
 128                     filename = Config.music_path + self.filename
 129
 130                 debug_print("{}oading « {} »".format(prefix, self.name))
 131                 self.mixer = self.mapping.mixer or Mixer()
 132                 initial_db_gain = gain(self.initial_volume_factor * 100)
 133                 self.audio_segment = pydub.AudioSegment \
 134                         .from_file(filename) \
 135                         .set_frame_rate(Config.frame_rate) \
 136                         .set_channels(Config.channels) \
 137                         .set_sample_width(Config.sample_width) \
 138                         .apply_gain(initial_db_gain)
 139                 self.sound_duration = self.audio_segment.duration_seconds
 140             except Exception as e:
 141                 error_print("failed to {}oad « {} »: {}".format(
 142                     prefix_s, self.name, e))
 143                 self.loading_error = e
 144                 self.fail()
 145             else:
 146                 self.success()
 147                 debug_print("{}oaded « {} »".format(prefix, self.name))
 148
 149     def on_enter_loaded(self):
 150         self.cleanup()
 151
 152     def cleanup(self):
 153         self.gain_effects = []
 154         self.set_gain(0, absolute=True)
 155         self.current_audio_segment = None
 156         self.volume = 100
 157         self.wait_event = threading.Event()
 158         self.current_loop = 0
 159
 160     def on_enter_loaded_playing(self):
 161         self.mixer.add_file(self)
 162
 163     # Machine related states
 164     def is_in_use(self):
 165         return self.is_loaded(allow_substates=True) and\
 166                 not self.is_loaded_stopped()
 167
 168     def is_in_use_not_stopping(self):
 169         return self.is_loaded_playing() or self.is_loaded_paused()
 170
 171     def is_unloadable(self):
 172         return self.is_loaded_stopped() or self.is_failed()
 173
 174     # Machine related triggers
 175     def trigger_stopped_events(self):
 176         self.mixer.remove_file(self)
 177         self.wait_event.set()
 178         self.cleanup()
 179
 180     # Actions and properties called externally
 181     @property
 182     def sound_position(self):
 183         if self.is_in_use():
 184             return self.current_frame / self.current_audio_segment.frame_rate
 185         else:
 186             return 0
 187
 188     def play(self, fade_in=0, volume=100, loop=0, start_at=0):
 189         self.set_gain(gain(volume) + self.mapping.master_gain, absolute=True)
 190         self.volume = volume
 191         if loop < 0:
 192             self.last_loop = float('inf')
 193         else:
 194             self.last_loop = loop
 195
 196         with self.music_lock:
 197             self.current_audio_segment = self.audio_segment
 198             self.current_frame = int(start_at * self.audio_segment.frame_rate)
 199
 200         self.start_playing()
 201
 202         if fade_in > 0:
 203             db_gain = gain(self.volume, 0)[0]
 204             self.set_gain(-db_gain)
 205             self.add_fade_effect(db_gain, fade_in)
 206
 207     def seek(self, value=0, delta=False):
 208         if not self.is_in_use_not_stopping():
 209             return
 210
 211         with self.music_lock:
 212             self.abandon_all_effects()
 213             if delta:
 214                 frame_count = int(self.audio_segment.frame_count())
 215                 frame_diff = int(value * self.audio_segment.frame_rate)
 216                 self.current_frame += frame_diff
 217                 while self.current_frame < 0:
 218                     self.current_loop -= 1
 219                     self.current_frame += frame_count
 220                 while self.current_frame > frame_count:
 221                     self.current_loop += 1
 222                     self.current_frame -= frame_count
 223                 if self.current_loop < 0:
 224                     self.current_loop = 0
 225                     self.current_frame = 0
 226                 if self.current_loop > self.last_loop:
 227                     self.current_loop = self.last_loop
 228                     self.current_frame = frame_count
 229             else:
 230                 self.current_frame = max(
 231                         0,
 232                         int(value * self.audio_segment.frame_rate))
 233
 234     def stop(self, fade_out=0, wait=False, set_wait_id=None):
 235         if self.is_loaded_playing():
 236             ms = int(self.sound_position * 1000)
 237             ms_fo = max(1, int(fade_out * 1000))
 238
 239             new_audio_segment = self.current_audio_segment[: ms+ms_fo] \
 240                 .fade_out(ms_fo)
 241             with self.music_lock:
 242                 self.current_audio_segment = new_audio_segment
 243             self.stop_playing()
 244             if wait:
 245                 self.mapping.add_wait(self.wait_event, wait_id=set_wait_id)
 246                 self.wait_end()
 247         elif self.is_loaded(allow_substates=True):
 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 state change
 279     def notify_state_change(self, **kwargs):
 280         for callback in self.state_change_callbacks:
 281             callback(self.state)
 282
 283     def subscribe_state_change(self, callback):
 284         if callback not in self.state_change_callbacks:
 285             self.state_change_callbacks.append(callback)
 286         callback(self.state)
 287
 288     def unsubscribe_state_change(self, callback):
 289         if callback in self.state_change_callbacks:
 290             self.state_change_callbacks.remove(callback)
 291
 292     # Callbacks
 293     def finished_callback(self):
 294         self.stopped()
 295
 296     def play_callback(self, out_data_length, frame_count):
 297         if self.is_loaded_paused():
 298             return b'\0' * out_data_length
 299
 300         with self.music_lock:
 301             [data, nb_frames] = self.get_next_sample(frame_count)
 302             if nb_frames < frame_count:
 303                 if self.is_loaded_playing() and\
 304                         self.current_loop < self.last_loop:
 305                     self.current_loop += 1
 306                     self.current_frame = 0
 307                     [new_data, new_nb_frames] = self.get_next_sample(
 308                             frame_count - nb_frames)
 309                     data += new_data
 310                     nb_frames += new_nb_frames
 311                 elif nb_frames == 0:
 312                     # FIXME: too slow when mixing multiple streams
 313                     threading.Thread(
 314                             name="MSFinishedCallback",
 315                             target=self.finished_callback).start()
 316
 317             return data.ljust(out_data_length, b'\0')
 318
 319     # Helpers
 320     def set_gain(self, db_gain, absolute=False):
 321         if absolute:
 322             self.db_gain = db_gain
 323         else:
 324             self.db_gain += db_gain
 325
 326     def get_next_sample(self, frame_count):
 327         fw = self.audio_segment.frame_width
 328
 329         data = b""
 330         nb_frames = 0
 331
 332         segment = self.current_audio_segment
 333         max_val = int(segment.frame_count())
 334
 335         start_i = max(self.current_frame, 0)
 336         end_i   = min(self.current_frame + frame_count, max_val)
 337         data += segment._data[start_i*fw : end_i*fw]
 338         nb_frames += end_i - start_i
 339         self.current_frame += end_i - start_i
 340
 341         volume_factor = self.volume_factor(self.effects_next_gain(nb_frames))
 342
 343         data = audioop.mul(data, Config.sample_width, volume_factor)
 344
 345         return [data, nb_frames]
 346
 347     def add_fade_effect(self, db_gain, fade_duration):
 348         if not self.is_in_use():
 349             return
 350
 351         self.gain_effects.append(GainEffect(
 352             "fade",
 353             self.current_audio_segment,
 354             self.current_loop,
 355             self.sound_position,
 356             self.sound_position + fade_duration,
 357             gain=db_gain))
 358
 359     def effects_next_gain(self, frame_count):
 360         db_gain = 0
 361         for gain_effect in self.gain_effects:
 362             [new_gain, last_gain] = gain_effect.get_next_gain(
 363                     self.current_frame,
 364                     self.current_loop,
 365                     frame_count)
 366             if last_gain:
 367                 self.set_gain(new_gain)
 368                 self.gain_effects.remove(gain_effect)
 369             else:
 370                 db_gain += new_gain
 371         return db_gain
 372
 373
 374     def volume_factor(self, additional_gain=0):
 375         return 10 ** ( (self.db_gain + additional_gain) / 20)
 376