Printed music recognition

The different steps to recognize printed music are described. The first step is to detect and to eliminate the staff lines. A robust method based on finding regions where are only the staff lines, linking between them the staff lines pieces in these regions is used. After staff lines elimination, symbols are isolated and a representation called attributed graph is constructed for each symbol. Thinning, polygonalization, spurious segments cleaning, and segment fusion are performed. A first classification, separating all notes with black heads from others, is performed. To recognize notes with black heads (beamed group or quarter notes), a straightforward structural approach using this representation is sufficient and efficient in most cases. In the ambiguous cases (chord or black head linked to two stems), an ellipse matching method is used. To recognize half notes and bar lines, a structural method using the graph is used