Add a common mixer

3 files changed, 66 insertions, 27 deletions

diff --git a/helpers/mapping.py b/helpers/mapping.py
index 84845fc..60c7691 100644
--- a/helpers/mapping.py
+++ b/helpers/mapping.py
@@ -8,6 +8,7 @@ import yaml
 import sys
 
 from .music_file import *
+from .mixer import Mixer
 from . import yml_file,gain
 
 class Mapping(RelativeLayout):
@@ -23,6 +24,7 @@ class Mapping(RelativeLayout):
         self.running = []
         Clock.schedule_interval(self.not_all_keys_ready, 1)
 
+        self.mixer = Mixer()
 
     @property
     def master_gain(self):
diff --git a/helpers/mixer.py b/helpers/mixer.py
new file mode 100644
index 0000000..9e8179a
--- /dev/null
+++ b/helpers/mixer.py
@@ -0,0 +1,50 @@
+import sounddevice as sd
+import audioop
+import time
+
+frame_rate   = 44100
+channels     = 2
+sample_width = 2
+
+class Mixer:
+    def __init__(self):
+        self.stream = sd.RawOutputStream(samplerate=frame_rate,
+                        channels=channels,
+                        dtype='int' + str(8*sample_width), # FIXME: ?
+                        latency="high",
+                        blocksize=5000,
+                        callback=self.play_callback,
+                        )
+        self.open_files = []
+
+    def add_file(self, music_file):
+        if music_file not in self.open_files:
+            self.open_files.append(music_file)
+        self.start()
+
+    def remove_file(self, music_file):
+        self.open_files.remove(music_file)
+        if len(self.open_files) == 0:
+            self.stop()
+
+    def stop(self):
+        self.stream.stop()
+
+    def start(self):
+        self.stream.start()
+
+    def play_callback(self, out_data, frame_count, time_info, status_flags):
+        out_data_length = len(out_data)
+        empty_data = b"\0" * out_data_length
+        data = b"\0" * out_data_length
+
+        for open_file in self.open_files:
+            file_data = open_file.play_callback(out_data_length, frame_count)
+
+            if data == empty_data:
+                data = file_data
+            elif file_data != empty_data:
+                data = audioop.add(data, file_data, sample_width)
+
+        out_data[:] = data
+
diff --git a/helpers/music_file.py b/helpers/music_file.py
index ebe458b..6da547b 100644
--- a/helpers/music_file.py
+++ b/helpers/music_file.py
@@ -3,7 +3,6 @@ import pydub
 import time
 from transitions.extensions import HierarchicalMachine as Machine
 
-import sounddevice as sd
 import os.path
 
 from .lock import Lock
@@ -27,7 +26,7 @@ class MusicFile(Machine):
             { 'trigger': 'pause', 'source':  'loaded_playing', 'dest': 'loaded_paused'},
             { 'trigger': 'unpause', 'source':  'loaded_paused', 'dest': 'loaded_playing'},
             { 'trigger': 'stop_playing', 'source': ['loaded_playing','loaded_paused'], 'dest': 'loaded_stopping'},
-            { 'trigger': 'stopped', 'source':  'loaded_stopping', 'dest': 'loaded_stopped'}
+            { 'trigger': 'stopped', 'source':  'loaded_stopping', 'dest': 'loaded_stopped', 'after': 'trigger_stopped_events'}
         ]
 
         Machine.__init__(self, states=states, transitions=transitions, initial='initial')
@@ -35,7 +34,6 @@ class MusicFile(Machine):
         self.volume = 100
         self.mapping = mapping
         self.filename = filename
-        self.stream = None
         self.name = name or filename
         self.audio_segment = None
         self.audio_segment_frame_width = 0
@@ -50,7 +48,7 @@ class MusicFile(Machine):
             try:
                 print("Loading « {} »".format(self.name))
                 db_gain = gain(self.volume_factor * 100)
-                self.audio_segment = pydub.AudioSegment.from_file(self.filename).set_frame_rate(44100).apply_gain(db_gain)
+                self.audio_segment = pydub.AudioSegment.from_file(self.filename).set_frame_rate(44100).set_channels(2).set_sample_width(2).apply_gain(db_gain)
                 self.audio_segment_frame_width = self.audio_segment.frame_width
                 self.sound_duration = self.audio_segment.duration_seconds
             except Exception as e:
@@ -94,26 +92,10 @@ class MusicFile(Machine):
             else:
                 self.a_s_with_effect = None
 
-        self.before_loaded_playing()
         self.start_playing()
 
-    def before_loaded_playing(self):
-        with self.music_lock:
-            segment = self.current_audio_segment
-
-            self.stream = sd.RawOutputStream(samplerate=segment.frame_rate,
-                            channels=segment.channels,
-                            dtype='int' + str(8*segment.sample_width), # FIXME: ?
-                            latency=1.,
-                            callback=self.play_callback,
-                            finished_callback=self.finished_callback
-                            )
-
     def on_enter_loaded_playing(self):
-        self.stream.start()
-
-    def on_enter_loaded_paused(self):
-        self.stream.stop()
+        self.mapping.mixer.add_file(self)
 
     def finished_callback(self):
         if self.is_loaded_playing():
@@ -121,10 +103,14 @@ class MusicFile(Machine):
         if self.is_loaded_stopping():
             self.stopped()
 
-    def on_enter_loaded_stopped(self):
+    def trigger_stopped_events(self):
+        self.mapping.mixer.remove_file(self)
         self.wait_event.set()
 
-    def play_callback(self, out_data, frame_count, time_info, status_flags):
+    def play_callback(self, out_data_length, frame_count):
+        if self.is_loaded_paused():
+            return b'\0' * out_data_length
+
         with self.music_lock:
             [data, nb_frames] = self.get_next_sample(frame_count)
             if nb_frames < frame_count:
@@ -135,9 +121,9 @@ class MusicFile(Machine):
                     data += new_data
                     nb_frames += new_nb_frames
                 elif nb_frames == 0:
-                    raise sd.CallbackStop
+                    threading.Thread(name = "MSFinishedCallback", target=self.finished_callback).start()
 
-            out_data[:] = data.ljust(len(out_data), b'\0')
+            return data.ljust(out_data_length, b'\0')
 
     def get_next_sample(self, frame_count):
         fw = self.audio_segment_frame_width
@@ -189,9 +175,10 @@ class MusicFile(Machine):
 
             # FIXME: stop fade_out puis seek -5 -> on abandonne le fade ? (cf
             # commentaire dans fonction seek
+            new_audio_segment = self.current_audio_segment[:ms + ms_fo].fade_out(ms_fo)
             with self.music_lock:
-                self.current_audio_segment = self.current_audio_segment[:ms + ms_fo].fade_out(ms_fo)
-                self.stop_playing()
+                self.current_audio_segment = new_audio_segment
+            self.stop_playing()
             if wait:
                 self.wait_end()
         else: