作者：Lin; Jiang; Ruimin; Hu; Xiaochen; Wang...audiocodingaudiobandwidthextensioncontextcorrelationdeeprecurrentneuralnetwork
摘要：Non-blind audio bandwidth exten-sion is a standard technique within contem-porary audio codecs to efficiently code audiosignals at low bitrates. In existing methods, inmost cases high frequencies signal is usuallygenerated by a duplication of the correspond-ing low frequencies and some parameters ofhigh frequencies. However, the perceptionquality of coding will significantly degradeif the correlation between high frequenciesand low frequencies becomes weak. In thispaper, we quantitatively analyse the correla-tion via computing mutual information value.The analysis results show the correlation alsoexists in low frequency signal of the contextdependent frames besides the current frame.In order to improve the perception quality ofcoding, we propose a novel method of highfrequency coarse spectrum generation to im-prove the conventional replication method. Inthe proposed method, the coarse high frequen-cy spectrums are generated by a nonlinearmapping model using deep recurrent neuralnetwork. The experiments confirm that theproposed method shows better performancethan the reference methods.
注：因版权方要求，不能公开全文，如需全文，请咨询杂志社
