Carnatic Raag Classification

Part of my research project for the last semester was building a Carnatic raag database. Once a substantial raag database was ready, we ran a number of experiments to check how well PCDs (pitch-class distribution) and PCDDs (pitch-class dyad distribution) perform the task of classifying the raags. It turned out that PCDs and PCDDs are very effective for this task. We achieved a 92.5% classification accuracy on 30 target raags, using a Bayesian Classifier. This shows that though raags in Carnatic music are different from raags in North Indian Classical music - in melodic, presentation and ornamentation, PCDs and PCDDs are still effective ( Using PCDs and PCDDs for North Indian raag classification is described in Dr.Parag Chordia's ISMIR '07 paper)

The Database :
The table below shows the various raags and their corresponding scale degree:


The following list describes the database audio. Each entry is a separate audio file with its tonic frequency and artist information included in the file name. The list also mentions the type of each of the audio file and its duration.

(Artists Legends: AKC-AKC Natarajan; KVN-Palghat KV Narayanaswamy; DKP-DK Pattammal; DKJ-DK Jayaraman; Nedunuri-Nedunuri Krishnamurthy; SSI-Semmangudi Srinivasa Iyer; TNK-Prof TN Krishnan; MS-MS Subbulakshmi; GNB-GN Balasubramanian; MMI-Madurai Mani Iyer; Sanjay-Sanjay Subrahmanyan;TNS-Madurai TN Seshagopalan; NS-Neyveli Santhanagopalan; Ramani-Flute Ramani;Kadri-Kadri Gopalnath; Ravikiran-Chitraveena Ravikiran; Hari - Shenkottai Hari )

1-Karaharapriya-AKC-307.wav 6:38 Clarinet
1-Karaharapriya-KVN-254.wav 8:01 Male Vocal
2-Kalyani-DKP-308.wav 6:37 Female Vocal
2-Kalyani-Nedunuri-262.wav 7:04 Male Vocal
3-Todi-SSI-260.wav 6:22 Male Vocal
3-Todi-TNK-260.wav 4:15 Violin
4-Sankarabharnam-MS-379.wav 10:39 Female Vocal
4-Sankarabharnam-SSI-265.wav 18:55 Male Vocal
5-Shanmugapriya-NS-274.wav 14:35 Male Vocal
5-Shanmugapriya-Nedunuri-263.wav 1:58 Male Vocal
6-Nattakurinji-GNB-251.wav 10:43 Male Vocal
6-Nattakurinji-Sanjay-293.wav 11:55 Male Vocal
6-Nattakurinji-Sanjay-violin-293.wav 4:30 Violin
7-Kambhoji-Lalgudi-260.wav 7:50 Violin
7-Kambhoji-Nedunuri-260.wav 17:41 Male Vocal
8-Mayamalavagowla-NS-273.wav 0:42 Male Vocal
9-Keeravani-MMI-266.wav 13:24 Male Vocal
10-SimhendraMadhyamam-270.wav 10:31 Male Vocal
11-Khamas-GNB-254.wav 8:27 Male Vocal
11-Khamas-Hari-263.wav 14:28 Male Vocal
12-Hamsadwani-Nedunuri-263.wav 1:35 Male Vocal
13-Mohanam-DKJ-283.wav 15:49 Male Vocal
13-Mohanam-DKP-297.wav 6:23 Female Vocal
14-Bilahari-HydBros-279.wav 1:35 Male Vocal
14-Bilahari-Violin-279.wav 3:37 Violin
15-Nalinakanthi-Violin-283.wav 1:24 Violin
16-Sahana-TNS-254.wav 11:25 Male Vocal
17-Bhairavi-Ramani-323.wav 18:59 Bamboo Flute
17-Bhairavi-SSI-262.wav 6:35 Male Vocal
18-Sriranjani-Kadri-243.wav 3:40 Saxophone
19-AnandhaBhairavi-SSI-262.wav 5:33 Male Vocal
20-Atana-NS-272.wav 1:10 Male Vocal
21-Dwijavanti-SSI-266.wav 1:43 Male Vocal
22-Dhanyasi-KVN-267.wav 10:15 Male Vocal
23-Hindolam-Flute-305.wav 5:50 Bamboo Flute
24-Varali-Vocal-267.wav 4:30 Male Vocal
25-Reethigowlai-Ravikiran-1-263.wav 1:08 Chitraveena
25-Reethigowlai-Ravikiran.wav 1:30 Chitraveena
26-Abheri-NS-273.wav 1:40 Male Vocal
27-Madhyamavathi-Ramani-325.wav 5:55 Bamboo Flute
28-Kaanada-Flute-195.wav 1:15 Bamboo Flute
29-Purvikalyani-SSI-254.wav 10:11 Male Vocal
30-Pantuvarali-Sanjay-290.wav 6:19 Male Vocal


Pitch Tracking :
YIN algorithm was used to compute the Pitch Class Distribution (PCDs) of the audio files. Since the tonic frequency varies between recordings, all the audio files' tonic was manually annotated. The figures below show the discriminative power of a single scale degree. This is boxplot of scale degree D across all target ragas :



Here is the boxplot of the scale degree Eb :