Audio Rendering of Mathematical Content

Text to speech (TTS) systems hold promise as an information access tool for the visually impaired. Current TTS systems can convert a typical text into a natural sounding speech. However, rendering Mathematical content (equations, bar graphs and pie charts) in audio is not a trivial task. Mathematical equations have to be read so that appropriate bracketing such as parentheses, fractions, superscripts and subscripts are unambiguously conveyed to the listener.

The ambiguity in most cases is caused if the listener is unable to identify the beginning and end of the mentioned demarkations. We proposed 4 techniques that introduce speech cues such as variations in pitch, rate, etc. We introduce non speech cues such as special sounds and 3-dimensional audio. We performed a subjective evaluation on the proposed ideas. Based on the evaluation metrics, we performed a comprehension test on participants both with and without vision impairment. Visually impaired participants were able to solve the problems with 95% accuracy with the proposed technique. The correctness was a meagre 30% with the current state of the art technology (a TTS).


Project collaborators

Saikrishna Rallabandi, Dr. Priyanka Srivastava and Dr. Kishore Prahallad