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文章介绍了ITU-T G.729.1 WB编解码器的超宽带扩展G.729.1 Annex E。G.729.1 Annex E在36 kbit/s～64 kbit/s的可变速率上对32 kHz采样的语音和音频信号进行超宽带编解码,编解码器具有5层结构,当高一层的码流被丢弃时不会影响到低一层码流的解码。在进行超宽带扩展时,利用已量化的宽带MDCT域参数产生高频(7 kHz～14 kHz)频段信号。第一层超宽带扩展层根据输入信号的特点采用了两种不同的编码模式。
The article introduces the ITU-T G.729.1 WB codec UWB extension G.729.1 Annex E. G.729.1 Annex E Ultra wideband codec for 32 kHz sampled speech and audio signals at 36 kbit / s to 64 kbit / s variable rate with a 5-layer codec, Discarded will not affect the decoding of the lower layer code stream. In ultra-wideband expansion, high-frequency (7 kHz to 14 kHz) band signals are generated using the quantized wideband MDCT domain parameters. The first layer of UWB uses two different encoding modes based on the characteristics of the input signal.