Music symbol recognition by a LAG-based combination model

Most of optical music recognition (OMR) systems work under the assumption that the input image is scanner-based. However, we propose in this paper, camera based OMR system. Camera based OMR has a challengeable work in un-controlled environment such as a light, perspective, curved, transparency distortions and uneven staff-lines which tend to incur more frequently. In addition, the loss in performance of binarization methods, line thickness variation and space variation between lines are inevitable. In order to solve these problems, we propose a novel and effective staff-line removal method based on following three main ideas. First, a state-of-the-art staff-line detection method, Stable Path, is used to extract staff-line skeletons of the music score. Second, a line adjacency graph (LAG) model is exploited in a different manner over segmentation to cluster pixel runs generated from the run-length encoding (RLE) of an music score image. Third, a two-pass staff-line removal pipeline called filament filtering is applied to remove clusters lying on the staff-line. A music symbol is comprised of several parts so-called primitives, but the combination of these parts to form music symbol is unlimited. It causes difficulty applying the state-of-the-art method for music symbol recognition. To overcome these challenges and deal with primitive parts separately, we proposed a combination model which consists of LAG model, Graph model, and Set model as a framework for music symbol recognition. Our method shows impressive results on music score images captured from cameras, and gives high performance when applied to the ICDAR/GREC 2013 database, and a Gamera synthetic database. We have compared to some commercial software and proved the expediency and efficiency of the proposed method.