TY - JOUR
T1 - A 5-kHz-bandwidth low-bit-rate speech coder
T2 - Bandwidth, noisiness, and opinion scores
AU - Harada, Noboru
AU - Ohmuro, Hitoshi
AU - Mano, Kazunori
PY - 2002/12/1
Y1 - 2002/12/1
N2 - With the development of PCs, Internet technology, and mobile communications, the demand for low-bit-rate speech coding schemes as well as for high-information-level natural speech have increased in recent years. While naturalness increases with the use of speech signals of broad frequency bands, more information is needed for coding. In this paper, we propose a 5-kHz-band speech coding scheme that clarifies the relationships between the frequency band feeling, noisiness, and subjective opinions on quality by means of evaluation experiments using multiple frequency bands, while allowing selection between low bit rate and naturalness. The proposed scheme operates in three bit-rate modes, 7.8, 5.75, and 3.95 kbit/s. Subjective quality evaluation tests confirm that the coding scheme achieves quality almost equal to G.729 (3.4-kHz bandwidth, 8 kbit/s) and G.722 (7-kHz bandwidth, 48 kbit/s) at 5.75 kbit/s and quality higher than these at 7.8 kbit/s.
AB - With the development of PCs, Internet technology, and mobile communications, the demand for low-bit-rate speech coding schemes as well as for high-information-level natural speech have increased in recent years. While naturalness increases with the use of speech signals of broad frequency bands, more information is needed for coding. In this paper, we propose a 5-kHz-band speech coding scheme that clarifies the relationships between the frequency band feeling, noisiness, and subjective opinions on quality by means of evaluation experiments using multiple frequency bands, while allowing selection between low bit rate and naturalness. The proposed scheme operates in three bit-rate modes, 7.8, 5.75, and 3.95 kbit/s. Subjective quality evaluation tests confirm that the coding scheme achieves quality almost equal to G.729 (3.4-kHz bandwidth, 8 kbit/s) and G.722 (7-kHz bandwidth, 48 kbit/s) at 5.75 kbit/s and quality higher than these at 7.8 kbit/s.
KW - 5-kHz bandwidth
KW - CELP
KW - Speech coding
UR - http://www.scopus.com/inward/record.url?scp=0036890618&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0036890618&partnerID=8YFLogxK
U2 - 10.1002/scj.1181
DO - 10.1002/scj.1181
M3 - Article
AN - SCOPUS:0036890618
VL - 33
SP - 110
EP - 119
JO - Systems and Computers in Japan
JF - Systems and Computers in Japan
SN - 0882-1666
IS - 14
ER -