Packet loss concealment apparatus for high-band in split-band wideband speech codec, and system for decoding bit-stream using the same

摘要

1. the art that the invention set forth in the claims ; The invention band-will on the high-band bit-stream decoding, and error concealment device system using the same in divided wideband speech codec. ; 2. The invention is to solve the technical challenges ; The present invention, band-by effectively concealing packet loss and frame error for the high-band in a wideband codec of the division method, the band for enabling a high-quality voice-high-band error concealment apparatus in a divided wideband speech codec, and him intended to provide the bit stream for decoding by the system. ; 3. The gist of the solution of the invention, ; The present invention, bands in the high-band error concealment apparatus in a divided wideband speech codec, the high band based on the error detection, the low-band LPC (Linear Predictive Coding) analysis for the synthetic voice transmitted from the low-band decoding unit of the external through a low-band LPC coefficient extracting means for extracting the low-band LPC coefficients; Here the high-band signal generating means for generating the low-band decoding unit and a low-band synthesized speech the low-band LPC coefficients and excitation signal extracting means by using the low-band LPC coefficients extracted from the received from; High band LPC coefficient generation means for generating a high-band LPC coefficients from the low-band LPC coefficients extracted in the low-band LPC coefficient extracting means; Here the high-band high-band speech synthesis means for the signal and high-band excitation signal generated by the generating means and by using the high-band LPC coefficients generated by the coefficient generating means and the band LPC synthesized speech band; And the high, but high by removing the low-band component through the band speech synthesis means that is included in the high-band speech synthesized including high pass filter means for outputting the band synthesized speech, is the high-band excitation signal generating means, a low-band excitation signal extracting means for outputting the low-low band synthesis for the audio extracted in the low-band LPC coefficient extracting means to apply the low-LPC analysis using a band LPC coefficient of the low-band excitation signal received from the band decoding unit; Wherein the low band excitation frequency conversion means for converting the sampling frequency and the sampling frequency of the band to fit the synthesized speech to create a mirror image of the band and the low band excitation signal output from the signal extraction means; And including a high-band excitation signal extracting means for outputting a low-band excitation signal and to remove the component from this signal, it converts the sampling frequency through said frequency converting means. ; 4. important use of the invention ; The invention band-yiyongdoem divided wideband speech codec or the like. ; High band, low band, high-band error concealment, wideband synthesized speech