Incremental FastPitch: Chunk-based High Quality Text to Speech
Muyang Du, Chuan Liu, Junjie Lai
TL;DR
Real-time streaming TTS requires incremental synthesis with low latency. Incremental FastPitch introduces a chunk-based FFT decoder with fixed-size past states and receptive-field constrained training to enable chunk-wise Mel generation while preserving parallelism. The work provides design details, analyzes receptive field effects, and compares static versus dynamic masking, showing speech quality close to the parallel baseline with substantially lower latency (approximately 22× real-time). These findings offer a practical approach for low-latency TTS in streaming applications on GPUs, enabling faster, more responsive voice synthesis without sacrificing quality.
Abstract
Parallel text-to-speech models have been widely applied for real-time speech synthesis, and they offer more controllability and a much faster synthesis process compared with conventional auto-regressive models. Although parallel models have benefits in many aspects, they become naturally unfit for incremental synthesis due to their fully parallel architecture such as transformer. In this work, we propose Incremental FastPitch, a novel FastPitch variant capable of incrementally producing high-quality Mel chunks by improving the architecture with chunk-based FFT blocks, training with receptive-field constrained chunk attention masks, and inference with fixed size past model states. Experimental results show that our proposal can produce speech quality comparable to the parallel FastPitch, with a significant lower latency that allows even lower response time for real-time speech applications.
