Title :
16 kbit/s wideband speech coding based on unequal subbands
Author :
Paulus, Jiirgen W. ; Schnitzler, Jiirgen
Author_Institution :
Inst. of Commun. Syst. & Data Process., Tech. Hochschule Aachen, Germany
Abstract :
We propose a split-band encoding scheme for 16 kbit/s wideband speech coding (50-7000 Hz), using 2 unequal subbands from 0-6 kHz and from 6-7 kHz. This approach was motivated by an experimental evaluation of the signal bandwidth of speech frames. The higher subband is simply represented by white noise with adjustment of the short term energy. For the lower subband code-excited linear prediction (CELP) is used. The analysis filter bank, which performs the unequal band splitting combined with critical subsampling of the sub-bands, is described. A bit error concealment technique and the bit allocation is also presented. By informal listening tests the speech quality was rated higher than the speech quality of the CCITT G.722 wideband codec operating at 48 kbit/s
Keywords :
band-pass filters; filtering theory; linear predictive coding; signal sampling; speech coding; speech intelligibility; speech processing; white noise; 0 Hz to 6 kHz; 16 kbit/s; 48 kbit/s; 50 to 7000 Hz; 6 to 7 kHz; CCITT G.722 wideband codec; CELP; analysis filter bank; bit allocation; bit error concealment; code-excited linear prediction; critical subsampling; experimental evaluation; informal listening tests; lower subband; short term energy; signal bandwidth; speech frames; speech quality; split-band encoding; unequal subbands; white noise; wideband speech coding; Bandwidth; Bit rate; Encoding; Filter bank; Performance analysis; Speech analysis; Speech codecs; Speech coding; White noise; Wideband;
Conference_Titel :
Acoustics, Speech, and Signal Processing, 1996. ICASSP-96. Conference Proceedings., 1996 IEEE International Conference on
Conference_Location :
Atlanta, GA
Print_ISBN :
0-7803-3192-3
DOI :
10.1109/ICASSP.1996.540406
