Text-to-Speech for Individuals with Vision Loss: A User Study

Individuals with vision loss use text-to-speech (TTS) for most of their interaction with devices, and rely on the quality of synthetic voices to a much larger extent than any other user group. A significant amount of local synthesis requests for Google TTS comes from TalkBack, the Android screenreader, making it our top client and making the visually-impaired users the heaviest consumers of the technology. Despite this, very little attention has been devoted to optimizing TTS voices for this user group and the feedback on TTS voices from the blind has been traditionally less-favourable. We present the findings from a TTS user experience study conducted by Google with visuallyimpaired screen reader users. The study comprised 14 focus groups and evaluated a total of 95 candidate voices with 90 participants across 3 countries. The study uncovered the distinctitve usage patterns of this user group, which point to different TTS requirements and voice preferences from those of sighted users.