关键词: 光学乐谱识别, 多声部乐谱, 音符, 基元抽取

Abstract: Toward recognizing complex multi-voice scores，new methods are proposed respectively for extracting three shapes of music note primitive：first，stem extraction is accomplished by searching stem candidates roughly from vertical run length units plus checking the candidates strictly in terms of horizontal run length properties，and this method can overcome the weaknesses of poor adaptability to the touched and overlapped notes；second，a “segmentation with feature testing” method for extracting note heads is designed，which employs the prior knowledge of notes to separate the note heads that touch；thirdly，an extraction method for beams similar to treating the note heads is proposed，and this method can avoid the troublesome touching issue in the former line detection method for extracting beams.The experiments show that the methods can extract note primitives in complex multi-voice scores successfully and effectively.

Key words: optical music recognition, multi-voice scores, music notes, primitives extraction