def _generate(self, input_sequence, generator_options):
    if len(generator_options.input_sections) > 1:
      raise mm.SequenceGeneratorException(
          'This model supports at most one input_sections message, but got %s' %
          len(generator_options.input_sections))
    if len(generator_options.generate_sections) != 1:
      raise mm.SequenceGeneratorException(
          'This model supports only 1 generate_sections message, but got %s' %
          len(generator_options.generate_sections))

    # This sequence will be quantized later, so it is guaranteed to have only 1
    # tempo.
    qpm = mm.DEFAULT_QUARTERS_PER_MINUTE
    if input_sequence.tempos:
      qpm = input_sequence.tempos[0].qpm

    steps_per_second = mm.steps_per_quarter_to_steps_per_second(
        self.steps_per_quarter, qpm)

    generate_section = generator_options.generate_sections[0]
    if generator_options.input_sections:
      input_section = generator_options.input_sections[0]
      primer_sequence = mm.trim_note_sequence(
          input_sequence, input_section.start_time, input_section.end_time)
      input_start_step = mm.quantize_to_step(
          input_section.start_time, steps_per_second, quantize_cutoff=0)
    else:
      primer_sequence = input_sequence
      input_start_step = 0

    last_end_time = (max(n.end_time for n in primer_sequence.notes)
                     if primer_sequence.notes else 0)
    if last_end_time > generate_section.start_time:
      raise mm.SequenceGeneratorException(
          'Got GenerateSection request for section that is before or equal to '
          'the end of the NoteSequence. This model can only extend sequences. '
          'Requested start time: %s, Final note end time: %s' %
          (generate_section.start_time, last_end_time))

    # Quantize the priming sequence.
    quantized_primer_sequence = mm.quantize_note_sequence(
        primer_sequence, self.steps_per_quarter)

    extracted_seqs, _ = polyphony_lib.extract_polyphonic_sequences(
        quantized_primer_sequence, start_step=input_start_step)
    assert len(extracted_seqs) <= 1

    generate_start_step = mm.quantize_to_step(
        generate_section.start_time, steps_per_second, quantize_cutoff=0)
    # Note that when quantizing end_step, we set quantize_cutoff to 1.0 so it
    # always rounds down. This avoids generating a sequence that ends at 5.0
    # seconds when the requested end time is 4.99.
    generate_end_step = mm.quantize_to_step(
        generate_section.end_time, steps_per_second, quantize_cutoff=1.0)

    if extracted_seqs and extracted_seqs[0]:
      poly_seq = extracted_seqs[0]
    else:
      # If no track could be extracted, create an empty track that starts at the
      # requested generate_start_step. This will result in a sequence that
      # contains only the START token.
      poly_seq = polyphony_lib.PolyphonicSequence(
          steps_per_quarter=(
              quantized_primer_sequence.quantization_info.steps_per_quarter),
          start_step=generate_start_step)

    # Ensure that the track extends up to the step we want to start generating.
    poly_seq.set_length(generate_start_step - poly_seq.start_step)
    # Trim any trailing end events to prepare the sequence for more events to be
    # appended during generation.
    poly_seq.trim_trailing_end_events()

    # Extract generation arguments from generator options.
    arg_types = {
        'temperature': lambda arg: arg.float_value,
        'beam_size': lambda arg: arg.int_value,
        'branch_factor': lambda arg: arg.int_value,
        'steps_per_iteration': lambda arg: arg.int_value
    }
    args = dict((name, value_fn(generator_options.args[name]))
                for name, value_fn in arg_types.items()
                if name in generator_options.args)

    # Inject the priming sequence as melody in the output of the generator, if
    # requested.
    # This option starts with no_ so that if it is unspecified (as will be the
    # case when used with the midi interface), the default will be to inject the
    # primer.
    if not (generator_options.args[
        'no_inject_primer_during_generation'].bool_value):
      melody_to_inject = copy.deepcopy(poly_seq)
      if generator_options.args['condition_on_primer'].bool_value:
        inject_start_step = poly_seq.num_steps
      else:
        # 0 steps because we'll overwrite poly_seq with a blank sequence below.
        inject_start_step = 0

      args['modify_events_callback'] = partial(
          _inject_melody, melody_to_inject, inject_start_step)

    # If we don't want to condition on the priming sequence, then overwrite
    # poly_seq with a blank sequence to feed into the generator.
    if not generator_options.args['condition_on_primer'].bool_value:
      poly_seq = polyphony_lib.PolyphonicSequence(
          steps_per_quarter=(
              quantized_primer_sequence.quantization_info.steps_per_quarter),
          start_step=generate_start_step)
      poly_seq.trim_trailing_end_events()

    total_steps = poly_seq.num_steps + (
        generate_end_step - generate_start_step)

    while poly_seq.num_steps < total_steps:
      # Assume it takes ~5 rnn steps to generate one quantized step.
      # Can't know for sure until generation is finished because the number of
      # notes per quantized step is variable.
      steps_to_gen = total_steps - poly_seq.num_steps
      rnn_steps_to_gen = 5 * steps_to_gen
      tf.logging.info(
          'Need to generate %d more steps for this sequence, will try asking '
          'for %d RNN steps' % (steps_to_gen, rnn_steps_to_gen))
      poly_seq = self._model.generate_polyphonic_sequence(
          len(poly_seq) + rnn_steps_to_gen, poly_seq, **args)
    poly_seq.set_length(total_steps)

    if generator_options.args['condition_on_primer'].bool_value:
      generated_sequence = poly_seq.to_sequence(qpm=qpm)
    else:
      # Specify a base_note_sequence because the priming sequence was not
      # included in poly_seq.
      generated_sequence = poly_seq.to_sequence(
          qpm=qpm, base_note_sequence=copy.deepcopy(primer_sequence))
    assert (generated_sequence.total_time - generate_section.end_time) <= 1e-5
    return generated_sequence
Пример #2
0
if len(note_seq_raw.key_signatures) > 1:
    print(
        "WARNING: more than one key signatures were found - only the first signature is used."
    )
original_key = note_seq_raw.key_signatures[0].key
transpose_interval = transpose_to_key - original_key

# PolyphonicSequence doesn't have a transpose function (like Music for monohonic)
for e in poly_seq:
    if e.pitch != None:
        e.pitch = e.pitch + transpose_interval

seq1_trans = poly_seq.to_sequence()  #qpm=60.0
midi_io.sequence_proto_to_midi_file(seq1_trans, out_file_trans)

inputs, labels = poly_encoder.encode(poly_seq)
print(inputs)
print(labels)

poly_pred = polyphony_lib.PolyphonicSequence(
    steps_per_quarter=steps_per_quarter)
events = []
for label in labels:
    event = poly_encoder.class_index_to_event(label, None)
    events.append(event)
    poly_pred.append(event)

print(events)

seq_pred = poly_pred.to_sequence()
midi_io.sequence_proto_to_midi_file(seq_pred, out_file_pred)