Class: Deftones::Context::PortAudioOutputStream

Inherits:
Object
  • Object
show all
Defined in:
lib/deftones/context.rb

Instance Method Summary collapse

Constructor Details

#initialize(context:) ⇒ PortAudioOutputStream

Returns a new instance of PortAudioOutputStream.



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# File 'lib/deftones/context.rb', line 223

def initialize(context:)
  @context = context
  @stream = nil
  @silence_cache = {}
end

Instance Method Details

#close ⇒ Object 



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# File 'lib/deftones/context.rb', line 243

def close
  return self unless @stream

  stream = @stream
  @stream = nil
  stream.close
  self
ensure
  Deftones::PortAudioSupport.release
end

#open_stream ⇒ Object (private) 



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# File 'lib/deftones/context.rb', line 262

def open_stream
  Deftones::PortAudioSupport.acquire!
  @stream = PortAudio::Stream.new(
    output: Deftones::PortAudioSupport.output_parameters(
      @context.channels,
      device_id: @context.output_device_id,
      label: @context.output_device_label,
      sample_rate: @context.sample_rate
    ),
    sample_rate: @context.sample_rate.to_f,
    frames_per_buffer: @context.buffer_size,
    &method(:process)
  )
rescue StandardError
  Deftones::PortAudioSupport.release
  raise
end

#process(_input, output, frame_count, _time_info, status_flags, _user_data) ⇒ Object (private) 



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# File 'lib/deftones/context.rb', line 280

def process(_input, output, frame_count, _time_info, status_flags, _user_data)
  @context.send(:record_stream_status_flags, status_flags)
  output.write_array_of_float(@context.send(:pull_realtime_samples, frame_count))
  :continue
rescue StandardError => error
  output.write_array_of_float(silence_for(frame_count)) unless output.null?
  @context.send(:handle_stream_error, error)
end

#silence_for(frame_count) ⇒ Object (private) 



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# File 'lib/deftones/context.rb', line 289

def silence_for(frame_count)
  @silence_cache[frame_count] ||= Array.new(frame_count * @context.channels, 0.0).freeze
end

#start ⇒ Object 



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# File 'lib/deftones/context.rb', line 229

def start
  open_stream unless @stream
  @stream.start
  self
end

#stop ⇒ Object 



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# File 'lib/deftones/context.rb', line 235

def stop
  return self unless @stream
  return self if @stream.stopped?

  @stream.stop
  self
end

#time ⇒ Object 



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# File 'lib/deftones/context.rb', line 254

def time
  return 0.0 unless @stream

  @stream.time
end