Voice Access to Malian linked data
28/03/2012 Leave a comment
A quick update related to the Malian Linked Data post. The Voices project is mainly concerned with voice access to Web information, to allow the local users in the developing countries themselves being able to access the data using simple 2g mobile phones. Therefore I have experimented with providing some form of voice access to the linked market data. This resulted in a small prototype demonstrator.
The voice service is built using VoiceXML , the industry standard for developing voice applications. Although in a deployment version we cannot assume that text-to-speech (TTS) libraries are available for the local languages, we here only implement English-language access to the data, using English TTS.
The prototype voice application is running on the Voxeo Evolution platform. The platform includes a voice browser, which is able to interpret VoiceXML documents, includes (English) TTS and provides a number of ways to access the Voice application. These include the Skype VoIP number +990009369996162208 and the local (Dutch) phone number +31208080855.
When any of these numbers is called, the voice application accesses a VoiceXML document hosted on a remote server. This document contains the dialogue structure for the application. In the current demonstrator, the caller is presented with three options, to browse the data by product or region, or to listen to the latest offering. The caller presses the code on his or her keypad (this is Dual Tone Multi-Frequency or DTMF). The voice application interprets the choice and forwards the caller to a new voice menu.
For products, the caller must select the type of product (“press 1 for Tamarind”, “press 2 for Honey”, etc.), for regions the caller is presented with a list of regions to choose from. Based on the choice the application then accesses a PHP document on the remote server, the choice is copied as a HTTP GET variable.
Based on the choice, a SPARQL query is constructed. This SPARQL query is then passed to the RadioMarche Linked Data server, which returns the appropriate results. For a product query, all (recent) offerings about that product are returned. The SPARQL
result is then transformed into VoiceXML and articulated to the caller.
The demonstrator is now in a very early prototype version, so not everything might work all the time.
The above paragraphs are also part of a paper submitted to the Downscale2012 workshop.