class_docstr: Extracts pianoroll tracks from a quantized NoteSequence.
class_docstr_tok: ["Extracts","pianoroll","tracks","from","a","quantized","NoteSequence","."]
code: def transform(self, input_object):
      quantized_sequence = input_object
      pianoroll_seqs, stats = extract_pianoroll_sequences(
          quantized_sequence,
          min_steps_discard=self._min_steps,
          max_steps_truncate=self._max_steps,
      )
      self._set_stats(stats)
      return pianoroll_seqs
  
file_path: magenta/magenta/pipelines/pianoroll_pipeline.py
imports: from magenta.pipelines import dag_pipeline
  from magenta.pipelines import event_sequence_pipeline
  from magenta.pipelines import note_sequence_pipelines
  from magenta.pipelines import pipeline
  from magenta.pipelines import pipelines_common
  from magenta.pipelines import statistics
  from note_seq import PianorollSequence
  from note_seq import sequences_lib
  from note_seq.protobuf import music_pb2
label_desc: Use image node_id 2 for calling the PianorollSequenceExtractor obj's underlying member method code with example usage: obj.transform(input_object) and returns: pianoroll_seqs