US 11,749,295 B2
Pitch emphasis apparatus, method and program for the same
Yutaka Kamamoto, Tokyo (JP); Ryosuke Sugiura, Tokyo (JP); and Takehiro Moriya, Tokyo (JP)
Assigned to NIPPON TELEGRAPH AND TELEPHONE CORPORATION, Tokyo (JP)
Filed by NIPPON TELEGRAPH AND TELEPHONE CORPORATION, Tokyo (JP)
Filed on Aug. 31, 2022, as Appl. No. 17/900,432.
Application 17/900,432 is a continuation of application No. 17/053,698, granted, now 11,468,907, previously published as PCT/JP2019/017137, filed on Apr. 23, 2019.
Claims priority of application No. 2018-091200 (JP), filed on May 10, 2018.
Prior Publication US 2022/0415341 A1, Dec. 29, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. G10L 21/04 (2013.01); G10L 19/06 (2013.01); G10L 13/08 (2013.01); G10L 21/0364 (2013.01); G10L 21/0332 (2013.01); G10L 25/90 (2013.01)
CPC G10L 21/0364 (2013.01) [G10L 21/0332 (2013.01); G10L 25/90 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A pitch emphasis apparatus that obtains an output signal having little unnaturalness to listeners by executing pitch enhancement processing on each of time segments of an input signal, the input signal being an audio signal, the apparatus comprising:
a pitch enhancing unit that carries out the following as the pitch enhancement processing:
for a time segment in which a spectral envelope of the signal has been determined to be flat, obtaining an output signal for each of times in the time segment, the output signal being a signal including a signal obtained by adding (1) a signal obtained by multiplying the signal of a time n−T0, further in the past than a time n by a number of samples T0 corresponding to a pitch period of the time segment, a pitch gain σ0 of the time segment, a predetermined constant B0, and a value greater than 0 and less than 1, to (2) the signal of the time n, and
for a time segment in which a spectral envelope of the signal has been determined not to be flat, obtaining an output signal for each of times in the time segment, the output signal being a signal including a signal obtained by adding (1) a signal obtained by multiplying the signal of a time n−T0, further in the past than a time n by the number of samples T0 corresponding to the pitch period of the time segment, the pitch gain σ0 of the time segment, and the predetermined constant B0, to (2) the signal of the time n.