import sounddevice as sd import audioop import time from . import Config sample_width = Config.sample_width def sample_width_to_dtype(sample_width): if sample_width == 1 or sample_width == 2 or sample_width == 4: return 'int' + str(8*sample_width) else: raise "Unknown sample width" def _latency(latency): if latency == "high" or latency == "low": return latency else: return float(latency) class Mixer: def __init__(self): self.stream = sd.RawOutputStream( samplerate=Config.frame_rate, channels=Config.channels, dtype=sample_width_to_dtype(Config.sample_width), latency=_latency(Config.latency), blocksize=Config.blocksize, 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): if music_file in self.open_files: 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