Automatic Speech Recognition

Automatic Speech Recognition (ASR) is one of the major activities that the centre is carrying out for the last six years. Speech recognition related prototypes (like Bangla digit recognizer, travel enquiry system, automatic phone dialing etc.) have been developed as proof of concepts. C-DAC, Kolkata is now one of the active members of DeitY (Department of Electronics and Information Technology) - ASR consortium. An IVR based real time isolated word speech recognizer on agricultural information domain has been developed as a part of the Phase I project under this consortium.

(under DeitY-ASR Consortium Phase I)


To implement and deploy a speech access based system for users to get prices of agricultural commodities over telephone/mobile. Such systems would provide excellent value-addition to the already existing website managed by the Ministry of Agriculture, since no computer, reading or writing skills are required for the proposed system. The languages covered are Bangla, Assamese, Marathi, Tamil, and Telugu. C-DAC Kolkata is responsible for the system development in Bangla Language.

System Features:

  • Remote access via mobile or landline phone, no need of computers and internet.
  • Easy to use: support Voice query and response, no need to type or touch.
  • 24 x 7 hrs Automated Service, no more waiting for reply from manual operators.
  • Mother tongue support, Bi-lingual (Bangla & English) prompts for better usability.
  • Helpful for illiterate and visually impaired farmers.
  • Toll free service via Kisan Call Centre.


  • Computer Telephony Interface (CTI) : Parallel handling of inbound/outbound calls over 30 voice channels.
  • Speech Recognition: Hidden Markov Model based speech recognition engine.

System Requirements:

Hardwares: Softwares:
ISDN-PRI / E1 Channel Linux Operating System
PRI Modem (ASMi-52) Asterisk Gateway Interface (AGI)
Asterisk Server High-Level Scripting
Sangoma A101 CTI Card External resources: MySQL, http,

Likely end user(s):

  • Farmers and other users interested in obtaining the latest prices of agricultural commodities by just speaking over the telephone.
  • This system will be especially useful for those who have no access to computers and Internet, and who may not have the required computer skills and reading/writing skills.
  • Successful completion of this project would also enable development of similar speech-based systems for many other applications like Voice enabled Railway travel enquiry system, Health informatics, Tourist guide, Weather forecasting etc.

Try Demonstration: Dial (033)-2357-9009

(Press 1 for Bangla prompt or 2 for English prompt. Then press 02 for getting commodity price)

Click here for Brochure