Silence compression coding/decoding method and device

(19)

(11)

EP 0 996 112 A3

(12)	EUROPEAN PATENT APPLICATION

(88)	Date of publication A3:
	26.06.2002 Bulletin 2002/26

(43)	Date of publication A2:
	26.04.2000 Bulletin 2000/17

(21)	Application number: 99120614.5

(22)	Date of filing: 18.10.1999

(51)	International Patent Classification (IPC)⁷: G10L 19/00

(84)	Designated Contracting States:
	AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE
	Designated Extension States:
	AL LT LV MK RO SI

(30)

Priority:

20.10.1998 JP 29815298

(71)	Applicant: NEC CORPORATION
	Tokyo (JP)

(72)	Inventor:
	Yui, Mieko, NEC Corporation Tokyo (JP)

(74)	Representative: Glawe, Delfs, Moll & Partner
	Patentanwälte Postfach 26 01 62 80058 München 80058 München (DE)

(54)	Silence compression coding/decoding method and device

(57) A silence compression coding / decoding method and device of the same enables sound quality of background noise at the time of decoding and transmission efficiency to be improved while selecting either silence compression coding processing or regular coding processing corresponding to background noise level of input speech signal in digital image / speech transmission. A background noise measuring section compares background noise component level 'Sm' in every input frame with discrimination threshold value data 'Srf' in background noise level discrimination section. When the background noise component level 'Sm' exceeds the discrimination threshold value data 'Srf', switches SW1, SW2 select coder (regular coding processing). When the background noise component level 'Sm' does not exceed the discrimination threshold value data 'Srf', switches SW1, SW2 select silence compression correspondence coder (silence compression coding processing). Thus each result of selection is transmitted to decoder. The decoder implements either regular decoding processing or decompression decoding processing according to in-active / active flag stored in frame transmitted from a silence compression coding selector. When the background noise level is large, the device reduces sound quality deterioration of the background noise at the time of decoding while implementing regular coding processing.

Search report