Speech coding software DualSpeech

摘要

Low-cost highly-efficient speech coding is important for personal multimedia communications. In particu- lar, the demand for real-time speech compression on a personal computer has been increasing. In this pa- per, we describe the algorithm of the DualSpeech codec developed by NTT and outline the software prod- uct. DualSpeech achieves real-time high-quality speech compression and decompression without any extra signal processors. The bit rate is 7.4kbit/s (high-quality mode) or 4.6kbit/s (low-bit-rate mode).