US 12,451,151 B2
Tone frame detector for digital speech
Thomas Clark, Westford, MA (US); and John C. Hardwick, Acton, MA (US)
Assigned to Digital Voice Systems, Inc., Westford, MA (US)
Filed by Digital Voice Systems, Inc., Westford, MA (US)
Filed on Apr. 8, 2022, as Appl. No. 17/716,845.
Prior Publication US 2023/0326473 A1, Oct. 12, 2023
Int. Cl. G10L 19/16 (2013.01); G06F 16/683 (2019.01); G10L 19/005 (2013.01); H04W 88/18 (2009.01)
CPC G10L 19/167 (2013.01) [G06F 16/683 (2019.01); G10L 19/005 (2013.01); H04W 88/181 (2013.01)] 26 Claims
OG exemplary drawing
 
1. A method for detecting and extracting tone data embedded in a voice bit stream that includes frames of bits, with some of the frames of bits being frames of non-tone bits and some of the frames of bits being frames of tone bits, the method comprising:
selecting a frame of bits from the voice bit stream;
analyzing the selected frame of bits to determine whether the selected frame of bits is a frame of tone bits; and
when the selected frame of bits is a frame of tone bits, extracting tone data from the selected frame of bits;
wherein analyzing the selected frame of bits comprises:
comparing bits of the selected frame of bits to sets of tone data to produce error criteria representative of differences between the selected frame of bits and each of multiple sets of tone data,
based on the error criteria, selecting a set of tone data that most closely corresponds to the bits of the selected frame of bits, and
when the error criteria corresponding to the selected set of tone data satisfies a set of thresholds, designating the selected frame of bits as a frame of tone bits, and
wherein extracting tone data from the selected frame of bits comprises providing the selected set of tone data as the extracted tone data.