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
  75         self.volume = 100
  76         self.mapping = mapping
  77         self.filename = filename
  78         self.name = name or filename
  79         self.audio_segment = None
  80         self.audio_segment_frame_width = 0
  81         self.initial_volume_factor = gain
  82         self.music_lock = Lock("music__" + filename)
  83         self.wait_event = threading.Event()
  84         self.db_gain = 0
  85         self.gain_effects = []
  86
  87         threading.Thread(name="MSMusicLoad", target=self.load).start()
  88
  89     def on_enter_loading(self):
  90         with file_lock:
  91             try:
  92                 debug_print("Loading « {} »".format(self.name))
  93                 self.mixer = self.mapping.mixer or Mixer()
  94                 initial_db_gain = gain(self.initial_volume_factor * 100)
  95                 self.audio_segment = pydub.AudioSegment \
  96                         .from_file(self.filename) \
  97                         .set_frame_rate(Config.frame_rate) \
  98                         .set_channels(Config.channels) \
  99                         .set_sample_width(Config.sample_width) \
 100                         .apply_gain(initial_db_gain)
 101                 self.audio_segment_frame_width = self.audio_segment.frame_width
 102                 self.sound_duration = self.audio_segment.duration_seconds
 103             except Exception as e:
 104                 error_print("failed to load « {} »: {}".format(self.name, e))
 105                 self.loading_error = e
 106                 self.fail()
 107             else:
 108                 self.success()
 109                 debug_print("Loaded « {} »".format(self.name))
 110
 111     def check_is_loaded(self):
 112         return self.state.startswith('loaded_')
 113
 114     def is_not_stopped(self):
 115         return self.check_is_loaded() and not self.is_loaded_stopped()
 116
 117     def is_paused(self):
 118         return self.is_loaded_paused()
 119
 120     @property
 121     def sound_position(self):
 122         if self.is_not_stopped():
 123             return self.current_frame / self.current_audio_segment.frame_rate
 124         else:
 125             return 0
 126
 127     def play(self, fade_in=0, volume=100, loop=0, start_at=0):
 128         self.set_gain(gain(volume) + self.mapping.master_gain, absolute=True)
 129         self.volume = volume
 130         self.current_loop = 0
 131         if loop < 0:
 132             self.last_loop = float('inf')
 133         else:
 134             self.last_loop = loop
 135
 136         with self.music_lock:
 137             self.current_audio_segment = self.audio_segment
 138             self.current_frame = int(start_at * self.audio_segment.frame_rate)
 139             if fade_in > 0:
 140                 db_gain = gain(self.volume, 0)[0]
 141                 self.set_gain(-db_gain)
 142                 self.gain_effects.append(GainEffect(
 143                     "fade",
 144                     self.current_audio_segment,
 145                     self.current_loop,
 146                     self.sound_position,
 147                     self.sound_position + fade_in,
 148                     gain=db_gain))
 149
 150         self.start_playing()
 151
 152     def on_enter_loaded_playing(self):
 153         self.mixer.add_file(self)
 154
 155     def finished_callback(self):
 156         if self.is_loaded_playing():
 157             self.stop_playing()
 158         if self.is_loaded_stopping():
 159             self.stopped()
 160
 161     def trigger_stopped_events(self):
 162         self.mixer.remove_file(self)
 163         self.wait_event.set()
 164
 165     def play_callback(self, out_data_length, frame_count):
 166         if self.is_loaded_paused():
 167             return b'\0' * out_data_length
 168
 169         with self.music_lock:
 170             [data, nb_frames] = self.get_next_sample(frame_count)
 171             if nb_frames < frame_count:
 172                 if self.is_loaded_playing() and\
 173                         self.current_loop < self.last_loop:
 174                     self.current_loop += 1
 175                     self.current_frame = 0
 176                     [new_data, new_nb_frames] = self.get_next_sample(
 177                             frame_count - nb_frames)
 178                     data += new_data
 179                     nb_frames += new_nb_frames
 180                 elif nb_frames == 0:
 181                     # FIXME: too slow
 182                     threading.Thread(
 183                             name="MSFinishedCallback",
 184                             target=self.finished_callback).start()
 185
 186             return data.ljust(out_data_length, b'\0')
 187
 188     def get_next_sample(self, frame_count):
 189         fw = self.audio_segment_frame_width
 190
 191         data = b""
 192         nb_frames = 0
 193
 194         segment = self.current_audio_segment
 195         max_val = int(segment.frame_count())
 196
 197         start_i = max(self.current_frame, 0)
 198         end_i   = min(self.current_frame + frame_count, max_val)
 199         data += segment._data[start_i*fw : end_i*fw]
 200         nb_frames += end_i - start_i
 201         self.current_frame += end_i - start_i
 202
 203         volume_factor = self.volume_factor(self.effects_next_gain(nb_frames))
 204
 205         data = audioop.mul(data, Config.sample_width, volume_factor)
 206
 207         return [data, nb_frames]
 208
 209     def seek(self, value=0, delta=False):
 210         # We don't want to do that while stopping
 211         if not (self.is_loaded_playing() or self.is_loaded_paused()):
 212             return
 213         with self.music_lock:
 214             self.abandon_all_effects()
 215             self.current_frame = max(
 216                     0,
 217                     int(delta) * self.current_frame
 218                         + int(value * self.audio_segment.frame_rate))
 219         # FIXME: si on fait un seek + delta, adapter le "loop"
 220
 221     def effects_next_gain(self, frame_count):
 222         db_gain = 0
 223         for gain_effect in self.gain_effects:
 224             [new_gain, last_gain] = gain_effect.get_next_gain(
 225                     self.current_frame,
 226                     self.current_loop,
 227                     frame_count)
 228             if last_gain:
 229                 self.set_gain(new_gain)
 230                 self.gain_effects.remove(gain_effect)
 231             else:
 232                 db_gain += new_gain
 233         return db_gain
 234
 235
 236     def abandon_all_effects(self):
 237         db_gain = 0
 238         for gain_effect in self.gain_effects:
 239             db_gain += gain_effect.get_last_gain()
 240
 241         self.gain_effects = []
 242         self.set_gain(db_gain)
 243
 244     def stop(self, fade_out=0, wait=False):
 245         if self.is_loaded_playing():
 246             ms = int(self.sound_position * 1000)
 247             ms_fo = max(1, int(fade_out * 1000))
 248
 249             new_audio_segment = self.current_audio_segment[: ms+ms_fo] \
 250                 .fade_out(ms_fo)
 251             with self.music_lock:
 252                 self.current_audio_segment = new_audio_segment
 253             self.stop_playing()
 254             if wait:
 255                 self.wait_end()
 256         else:
 257             self.stop_playing()
 258             self.stopped()
 259
 260     def volume_factor(self, additional_gain):
 261         return 10 ** ( (self.db_gain + additional_gain) / 20)
 262
 263     def set_gain(self, db_gain, absolute=False):
 264         if absolute:
 265             self.db_gain = db_gain
 266         else:
 267             self.db_gain += db_gain
 268
 269     def set_volume(self, value, delta=False, fade=0):
 270         [db_gain, self.volume] = gain(
 271                 value + int(delta) * self.volume,
 272                 self.volume)
 273
 274         if fade > 0:
 275             self.gain_effects.append(GainEffect(
 276                 "fade",
 277                 self.current_audio_segment,
 278                 self.current_loop,
 279                 self.sound_position,
 280                 self.sound_position + fade,
 281                 gain=db_gain))
 282         else:
 283             self.set_gain(db_gain)
 284
 285     def wait_end(self):
 286         self.wait_event.clear()
 287         self.wait_event.wait()
 288