|Authors||Sankalp Gulati, Kaustuv Kanti Ganguli, Swapnil Gupta, Ajay Srinivasamurthy|
|Affiliation||Music Technology Group, Universitat Pompeu Fabra, Barcelona|
We demonstrate a real-time raga recognition system capable of running on web-browsers. Our system follows a hierarchical approach that uses pitch class profiles, pitch transitions and melodic phrases for raga recognition. We process the input audio signal in real-time to estimate pitch, and subsequently perform melody transcription. For each raga we store a dictionary of its svaras, svara transitions, and typical melodic phrases. The likelihood of each raga is updated in real-time based on the transcribed melody. In order to highlight the melodic events that are characteristic of a raga, we perform a dynamic visualization of the evolution of the salience of all the ragas.
The concept of raga in Indian art music (hereafter IAM) is quite complex and a comprehensive definition involves multiple dimensions including melody, rhythmicity, timbral texture etc. While raga recognition, by itself, is a very interesting and widely addressed task from both musicological and MIR researchers, we address the problem from a viewpoint that additionally leads to exploring the raga space through a gradual unfolding of the svaras. There exists a hierarchical model in the melodic framework of a raga, viz., (i) ground level: svaras that constitute the scale of the raga (with certain svaras being pseudo-steady for a longer duration), (ii) intermediate level: allowed svara transitions to make meaningful note sequences, and (iii) top level: characteristic phrases that is conclusive to recognise a raga.
Our current system employs real-time pitch tracking on web browser, real-time melody transcription, dynamic raga recognition based on a hierarchical model of melodic descriptors. Apart from being an efficient raga recognition system, this facilitates a tool to explore the 'raga space' and discover insightful relationships among alied ragas which is otherwise not explicit. The proposed system would also find its use among advanced students of IAM in the pedagogical scenario where one could explore the raga space and appreciate the nuances of phrase progression while unfolding a raga.