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(Machine):
  18     def __init__(self, filename, mapping, name=None, gain=1):
  19         states = [
  20             'initial',
  21             'loading',
  22             'failed',
  23             {
  24                 'name': 'loaded',
  25                 'children': ['stopped', 'playing', 'paused', 'stopping']
  26             }
  27         ]
  28         transitions = [
  29             {
  30                 'trigger': 'load',
  31                 'source': 'initial',
  32                 'dest': 'loading'
  33             },
  34             {
  35                 'trigger': 'fail',
  36                 'source': 'loading',
  37                 'dest': 'failed'
  38             },
  39             {
  40                 'trigger': 'success',
  41                 'source': 'loading',
  42                 'dest': 'loaded_stopped'
  43             },
  44             {
  45                 'trigger': 'start_playing',
  46                 'source': 'loaded_stopped',
  47                 'dest': 'loaded_playing'
  48             },
  49             {
  50                 'trigger': 'pause',
  51                 'source': 'loaded_playing',
  52                 'dest': 'loaded_paused'
  53             },
  54             {
  55                 'trigger': 'unpause',
  56                 'source': 'loaded_paused',
  57                 'dest': 'loaded_playing'
  58             },
  59             {
  60                 'trigger': 'stop_playing',
  61                 'source': ['loaded_playing','loaded_paused'],
  62                 'dest': 'loaded_stopping'
  63             },
  64             {
  65                 'trigger': 'stopped',
  66                 'source': 'loaded_stopping',
  67                 'dest': 'loaded_stopped',
  68                 'after': 'trigger_stopped_events'
  69             }
  70         ]
  71
  72         Machine.__init__(self, states=states,
  73                 transitions=transitions, initial='initial',
  74                 ignore_invalid_triggers=True)
  75
  76         self.volume = 100
  77         self.mapping = mapping
  78         self.filename = filename
  79         self.name = name or filename
  80         self.audio_segment = None
  81         self.audio_segment_frame_width = 0
  82         self.initial_volume_factor = gain
  83         self.music_lock = Lock("music__" + filename)
  84         self.wait_event = threading.Event()
  85         self.db_gain = 0
  86         self.gain_effects = []
  87
  88         threading.Thread(name="MSMusicLoad", target=self.load).start()
  89
  90     def on_enter_loading(self):
  91         with file_lock:
  92             try:
  93                 debug_print("Loading « {} »".format(self.name))
  94                 self.mixer = self.mapping.mixer or Mixer()
  95                 initial_db_gain = gain(self.initial_volume_factor * 100)
  96                 self.audio_segment = pydub.AudioSegment \
  97                         .from_file(self.filename) \
  98                         .set_frame_rate(Config.frame_rate) \
  99                         .set_channels(Config.channels) \
 100                         .set_sample_width(Config.sample_width) \
 101                         .apply_gain(initial_db_gain)
 102                 self.audio_segment_frame_width = self.audio_segment.frame_width
 103                 self.sound_duration = self.audio_segment.duration_seconds
 104             except Exception as e:
 105                 error_print("failed to load « {} »: {}".format(self.name, e))
 106                 self.loading_error = e
 107                 self.fail()
 108             else:
 109                 self.success()
 110                 debug_print("Loaded « {} »".format(self.name))
 111
 112     def check_is_loaded(self):
 113         return self.state.startswith('loaded_')
 114
 115     def is_not_stopped(self):
 116         return self.check_is_loaded() and not self.is_loaded_stopped()
 117
 118     def is_paused(self):
 119         return self.is_loaded_paused()
 120
 121     @property
 122     def sound_position(self):
 123         if self.is_not_stopped():
 124             return self.current_frame / self.current_audio_segment.frame_rate
 125         else:
 126             return 0
 127
 128     def play(self, fade_in=0, volume=100, loop=0, start_at=0):
 129         # FIXME: create a "reinitialize" method
 130         self.gain_effects = []
 131         self.set_gain(gain(volume) + self.mapping.master_gain, absolute=True)
 132         self.volume = volume
 133         self.current_loop = 0
 134         if loop < 0:
 135             self.last_loop = float('inf')
 136         else:
 137             self.last_loop = loop
 138
 139         with self.music_lock:
 140             self.current_audio_segment = self.audio_segment
 141             self.current_frame = int(start_at * self.audio_segment.frame_rate)
 142             if fade_in > 0:
 143                 db_gain = gain(self.volume, 0)[0]
 144                 self.set_gain(-db_gain)
 145                 self.gain_effects.append(GainEffect(
 146                     "fade",
 147                     self.current_audio_segment,
 148                     self.current_loop,
 149                     self.sound_position,
 150                     self.sound_position + fade_in,
 151                     gain=db_gain))
 152
 153         self.start_playing()
 154
 155     def on_enter_loaded_playing(self):
 156         self.mixer.add_file(self)
 157
 158     def finished_callback(self):
 159         if self.is_loaded_playing():
 160             self.stop_playing()
 161         if self.is_loaded_stopping():
 162             self.stopped()
 163
 164     def trigger_stopped_events(self):
 165         self.mixer.remove_file(self)
 166         self.wait_event.set()
 167
 168     def play_callback(self, out_data_length, frame_count):
 169         if self.is_loaded_paused():
 170             return b'\0' * out_data_length
 171
 172         with self.music_lock:
 173             [data, nb_frames] = self.get_next_sample(frame_count)
 174             if nb_frames < frame_count:
 175                 if self.is_loaded_playing() and\
 176                         self.current_loop < self.last_loop:
 177                     self.current_loop += 1
 178                     self.current_frame = 0
 179                     [new_data, new_nb_frames] = self.get_next_sample(
 180                             frame_count - nb_frames)
 181                     data += new_data
 182                     nb_frames += new_nb_frames
 183                 elif nb_frames == 0:
 184                     # FIXME: too slow when mixing multiple streams
 185                     threading.Thread(
 186                             name="MSFinishedCallback",
 187                             target=self.finished_callback).start()
 188
 189             return data.ljust(out_data_length, b'\0')
 190
 191     def get_next_sample(self, frame_count):
 192         fw = self.audio_segment_frame_width
 193
 194         data = b""
 195         nb_frames = 0
 196
 197         segment = self.current_audio_segment
 198         max_val = int(segment.frame_count())
 199
 200         start_i = max(self.current_frame, 0)
 201         end_i   = min(self.current_frame + frame_count, max_val)
 202         data += segment._data[start_i*fw : end_i*fw]
 203         nb_frames += end_i - start_i
 204         self.current_frame += end_i - start_i
 205
 206         volume_factor = self.volume_factor(self.effects_next_gain(nb_frames))
 207
 208         data = audioop.mul(data, Config.sample_width, volume_factor)
 209
 210         return [data, nb_frames]
 211
 212     def seek(self, value=0, delta=False):
 213         # We don't want to do that while stopping
 214         if not (self.is_loaded_playing() or self.is_loaded_paused()):
 215             return
 216         with self.music_lock:
 217             self.abandon_all_effects()
 218             if delta:
 219                 frame_count = int(self.audio_segment.frame_count())
 220                 frame_diff = int(value * self.audio_segment.frame_rate)
 221                 self.current_frame += frame_diff
 222                 while self.current_frame < 0:
 223                     self.current_loop -= 1
 224                     self.current_frame += frame_count
 225                 while self.current_frame > frame_count:
 226                     self.current_loop += 1
 227                     self.current_frame -= frame_count
 228                 if self.current_loop < 0:
 229                     self.current_loop = 0
 230                     self.current_frame = 0
 231                 if self.current_loop > self.last_loop:
 232                     self.current_loop = self.last_loop
 233                     self.current_frame = frame_count
 234             else:
 235                 self.current_frame = max(
 236                         0,
 237                         int(value * self.audio_segment.frame_rate))
 238
 239     def effects_next_gain(self, frame_count):
 240         db_gain = 0
 241         for gain_effect in self.gain_effects:
 242             [new_gain, last_gain] = gain_effect.get_next_gain(
 243                     self.current_frame,
 244                     self.current_loop,
 245                     frame_count)
 246             if last_gain:
 247                 self.set_gain(new_gain)
 248                 self.gain_effects.remove(gain_effect)
 249             else:
 250                 db_gain += new_gain
 251         return db_gain
 252
 253
 254     def abandon_all_effects(self):
 255         db_gain = 0
 256         for gain_effect in self.gain_effects:
 257             db_gain += gain_effect.get_last_gain()
 258
 259         self.gain_effects = []
 260         self.set_gain(db_gain)
 261
 262     def stop(self, fade_out=0, wait=False, set_wait_id=None):
 263         if self.is_loaded_playing():
 264             ms = int(self.sound_position * 1000)
 265             ms_fo = max(1, int(fade_out * 1000))
 266
 267             new_audio_segment = self.current_audio_segment[: ms+ms_fo] \
 268                 .fade_out(ms_fo)
 269             with self.music_lock:
 270                 self.current_audio_segment = new_audio_segment
 271             self.stop_playing()
 272             if wait:
 273                 if set_wait_id is not None:
 274                     self.mapping.add_wait_id(set_wait_id, self.wait_event)
 275                 self.wait_end()
 276         else:
 277             self.stop_playing()
 278             self.stopped()
 279
 280     def volume_factor(self, additional_gain):
 281         return 10 ** ( (self.db_gain + additional_gain) / 20)
 282
 283     def set_gain(self, db_gain, absolute=False):
 284         if absolute:
 285             self.db_gain = db_gain
 286         else:
 287             self.db_gain += db_gain
 288
 289     def set_volume(self, value, delta=False, fade=0):
 290         [db_gain, self.volume] = gain(
 291                 value + int(delta) * self.volume,
 292                 self.volume)
 293
 294         if not (self.is_loaded_playing() or self.is_loaded_paused()):
 295             return
 296
 297         if fade > 0:
 298             self.gain_effects.append(GainEffect(
 299                 "fade",
 300                 self.current_audio_segment,
 301                 self.current_loop,
 302                 self.sound_position,
 303                 self.sound_position + fade,
 304                 gain=db_gain))
 305         else:
 306             self.set_gain(db_gain)
 307
 308     def wait_end(self):
 309         self.wait_event.clear()
 310         self.wait_event.wait()
 311