Before revision:  The latter reduces the computational complexity of LPCNet through combining multi-band and multi-time strategies . The multi-band strategy enables the LPCNet to generate sub-band signals in each inference. By predicting the sub-band signals of adjacent time in one forward operation, the multi-time strategy further decreases the number of inferences required. Due to the multi-band and multi-time strategy , the vocoder speed is increased by 2.75x on a single CPU and the MOS (mean opinion score)degradation is slight .
After revision:  The latter reduces the computational complexity of LPCNet through combining multi-band and multi-time strategies (from 2.8 to 1.0 GFLOP). Due to these strategies , the vocoder speed is increased by 2.75x on a single CPU and the MOS (mean opinion score)degradation is slight .