US Patent 9734817 Text-to-speech task scheduling

To prioritize the processing text-to-speech (TTS) tasks, a TTS system may determine, for each task, an amount of time prior to the task reaching underrun, that is the time before the synthesized speech output to a user catches up to the time since a TTS task was originated. The TTS system may also prioritize tasks to reduce the amount of time between when a user submits a TTS request and when results are delivered to the user. When prioritizing tasks, such as allocating resources to existing tasks or accepting new tasks, the TTS system may prioritize tasks with the lowest amount of time prior to underrun and/or tasks with the longest time prior to delivery of first results.