Granted Patent B2

US 8,949,121 · App. 12/864,951 · Granted Feb 3, 2015

Abstract

Claims (31)

1. A method for the generation of Silence Insertion Description (“SID”) frames for a discontinuous transmission of background noise parameters via a transmission network, the method comprising:

producing first narrowband SID information of background noise for inclusion into a first SID frame as a first component of the first SID frame via at least one encoder device communicatively connected to the transmission network;

producing second wideband SID information of the background noise for inclusion into the first SID frame as a second component of the first SID frame via the at least one encoder device;

producing third SID information of the background noise for inclusion into the first SID frame as a third component of the first SID frame via the at least one encoder device;

forming the first SID frame to include the first component, the second component and the third component, the first, second and third components being in separate areas of the formed first SID frame;

analyzing, via the at least one encoder device, the background noise based on at least one of energy and frequency distribution during a phase that precedes transmission of the first SID frame;

transmitting the first SID frame via the transmission network in response to detecting one of:

(i) a change in a wideband component of the background noise is equal to or exceeds a predetermined threshold,

(ii) an occurrence indicating that an update to the narrowband SID information is to be sent; and

receiving, by a receiver side, the first SID frame; and

determining, by the receiver side, whether comfort noise should be generated based on the first component of the first SID frame or whether comfort noise should be generated based on the second component of the first SID frame or whether comfort noise should be generated based on the third component of the first SID frame.

2. The method of claim 1 further comprising determining the background noise parameters of a narrowband portion of the background noise by determining an energy and autocorrection function of the background noise.

3. The method of claim 2 further comprising determining the background noise parameters of the narrowband portion at 100 millisecond increments.

4. The method of claim 1 further comprising determining background noise parameters during a hangover period in a transition from a signal categorized as speech to a signal categorized as background noise.

5. The method of claim 1 further comprising attenuating a wideband portion of the background noise.

6. The method of claim 1 further comprising filtering said background noise through a downstream de-emphasis post filter.

7. The method of claim 1 wherein the at least one encoder device recalculates an averaged energy and autocorrelation function after a predetermined amount of time.

8. The method of claim 1 wherein the creating of the SID frames occurs after a speech pause is recognized.

9. The method of claim 1 further comprising a decoder communicatively coupled to the transmission network generating comfort noise after receipt of the SID frames, receipt of the SID frames indicating a detected speech pause to the decoder.

10. The method of claim 1 wherein the SID frames for the discontinuous transmission of background noise parameters via the transmission network comprise a plurality of speech recognition frames defining a first hangover period and a plurality of discontinuous transfer (“DTX”) frames defining a second hangover period to gather information about background noise to exclusively learn about the background noise and to indicate that no speech signals are present in the DTX frames defining the second hangover period;

the at least one encoder separately encoding a wideband portion and a narrowband portion of the background noise information of the SID frames to be at least some of the DTX frames of the second hangover period; and

the second hangover period occurring after the first hangover period.

11. The method of claim 10 further comprising a decoder device communicatively coupled to the transmission network generating comfort noise in response to receiving at least one of the DTX frames.

12. The method of claim 11 wherein the DTX frames of the second hangover period is comprised of at least five frames and the frames of the first hangover period is comprised of at least two frames.

13. The method of claim 10 further comprising a decoder device communicatively coupled to the transmission network generating comfort noise in response to receiving the encoded narrowband portion of the background noise.

14. The method of claim 10 further comprising a decoder device communicatively coupled to the transmission network generating comfort noise in response to receiving the encoded wideband portion of the background noise.

15. The method of claim 1 further comprising:

initiating a hangover period in response to detecting a change in a speech pause; and

wherein the producing of the narrowband SID information, producing of the third SID information, and producing of the wideband SID information occurs during a hangover period.

16. The method of claim 1 wherein the first component of the first SID frame has a first data length, the second component of the SID frame has a second data length and the third component of the first SID frame has a third data length, the first data length being greater than the third data length and the first data length also being smaller than the second data length.

17. The method of claim 16 wherein the first narrowband SID information is produced by encoding at a first bit rate, the second wideband SID information is produced by encoding at a second bit rate that is greater than the first bit rate, and the third SID information is produced by encoding at a third bit rate that is smaller than the second bit rate and is greater than the first bit rate.

Assignments (12)