A Beat Tracking Approach to Complete Description of Rhythm in Indian Classical Music

In this paper, we propose a beat tracking and beat similarity based approach to rhythm description in Indian Classical Music. We present an algorithm that uses a beat similarity matrix and inter onset interval histogram to automatically extract the sub-beat structure and the long-term periodicity of a musical piece. From this information, we can then obtain a rank ordered set of candidates for the tāla cycle period and the naḍe (sub-beat structure). The tempo, beat locations along with the tāla and naḍe candidates provide a better overall rhythm description of the musical piece. The algorithm is tested on a manually annotated Carnatic music dataset (CMDB) and Indian light classical music dataset (ILCMDB). The allowed metrical levels recognition accuracy of the algorithm on ILCMDB is 79.3% and 72.4% for the sub-beat structure and the tāla, respectively. The accuracy on the difficult CMDB was poorer with 68.6% and 51.1% for naḍe and tāla, respectively. The analysis of the algorithm's performancemotivates us to explore knowledge based approaches to tāla recognition.