Speech packetizing based linguistic processing to improve voice quality

• US 6,728,672 B1
• Filed: 06/30/2000
• Issued: 04/27/2004
• Est. Priority Date: 06/30/2000
• Status: Expired due to Term

• Current Assignee: Avaya Incorporated
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Will, Craig A.
• Primary Examiner(s): Dorvil, Richemond
• Assistant Examiner(s): Lerner, Martin
• Application Number:
  US09/608,552
• Time in Patent Office: 1,397 Days
• Field of Search: 704/231, 704/233, 704/270.1, 704/249, 704/251, 704/254
• US Class Current: 704/233
• CPC Class Codes: G10L 19/22 Mode decision, i.e. based on audio signal content versus external parameters
• CPC Class Codes: G10L 2015/025 Phonemes, fenemes or fenones being the recognition units
• CPC Class Codes: G10L 25/69 for evaluating synthetic or decoded voice signals

Abstract

An embodiment of the present invention is a technique of establishing a telephone communication using a packet switching communications network. Digitized voice information is received from a speaker. The voice information is placed into a payload of a first packet. The first packet is transmitted to a recipient. A significance to voice quality of the voice information contained in the first packet is calculated. One or more additional packets is transmitted to the recipient containing the voice information if the significance of the voice information is above a threshold level. One or more phonemes contained in the voice information is identified. A value from memory for each identified phoneme representing the significance to voice quality of that phoneme is retrieved. The measure of significance for the voice information is set to the maximum of the values for all of the phonemes contained in the voice information.

Claims

1. A method of establishing a telephone communication using a packet switching communications network, comprising:

digitizing voice information received from a speaker;

placing the voice information into a payload of a first packet;

transmitting the first packet to a recipient;

calculating a significance to voice quality of the voice information contained in the first packet; and

transmitting one or more additional packets to the recipient containing the voice information if the significance of the voice information is above a threshold level;

wherein calculating the significance to voice quality of the voice information comprises;

identifying one or more phonemes contained in the voice information;

retrieving a value from memory for each identified phoneme representing the significance to voice quality of that phoneme; and

setting the measure of significance for the voice information to the maximum of the values for all of the phonemes contained in the voice information.

2. The method of claim 1, wherein the identification of the phonemes in the voice information is performed by a hidden Markov model speech recognition system.

3. The method of claim 1, wherein a delay is introduced after the transmission of said first packet and before at least one of the additional packets containing the voice information.

4. The method of claim 1, wherein the packet switching communications network comprises at least one local area network and a wide area network.

5. The method of claim 4, wherein the local area network comprises an Ethernet.

6. The method of claim 4, wherein the wide area network comprises a corporate Intranet.

7. The method of claim 1, wherein the transmission of the first packet is carried out by a network telephone connected directly to a local area network, and calculating the significance to voice quality and transmission of the one or more additional packets is carried out by a server elsewhere in the local area network.

8. The method of claim 1, wherein the source of the speech is a telephone and origination of all packets and calculating the significance to voice quality is carried out by a server elsewhere in the network.

9. The method of claim 1, wherein a source of the voice information is a personal computer and origination of all packets and calculating the significance to voice quality is carried out by the personal computer.

10. A computing device comprising a processor for determining a significance to voice quality of voice information contained in a first packet and for transmitting one or more additional packets containing the voice information if the significance of the voice information is above a threshold level;

wherein said processor is capable of;

identifying one or more phonemes contained in the voice information;

retrieving a value from memory for each identified phoneme representing the significance to voice quality of that phoneme; and

setting the measure of significance for the voice information to the maximum of the values for all of the phonemes contained in the voice information.

11. The computing device of claim 10, wherein said processor is capable of identifying the phonemes in the voice information using a hidden Markov model speech recognition system.

12. The computing device of claim 10, wherein said processor is capable of introducing a delay after the transmission of said first packet and before at least one of the additional packets containing the voice information.

13. The computing device of claim 10, wherein said processor is capable of transmitting said first packet and said one or more additional packets through a packet switching communications network.

14. The computing device of claim 10, wherein said packet switching communications network comprises at least one local area network and a wide area network.

15. The computing device of claim 14, wherein the local area network comprises an Ethernet.

16. The computing device of claim 14, wherein the wide area network comprises a corporate Intranet.

17. The computing device of claim 10, wherein said processor comprises:

a network interface for transmitting and receiving packets; and

a microprocessor for receiving said first packet from said network interface, for determining the significance to voice quality of the voice information contained in a packet, and for transmitting through said network interface one or more additional packets containing the voice information if the significance of the voice information is above a threshold level.

18. The computing device of claim 17, further including a digital signal co-processor for assisting in determining the significance to voice quality of the voice information contained in a packet.

19. The computing device of claim 10, wherein said processor comprises:

speech recognition system for identifying one or more linguistic units of the voice information;

a speech information significance evaluator for evaluating the significance of the identified one or more linguistic units to voice quality;

a packet retransmission decision node for generating a control signal if said significance is above said threshold; and

a packet transmission control for transmitting one or more additional packets in response to said control signal.

20. The computing device of claim 19, wherein said speech recognition system comprises:

a spectral analyzer for identifying frequency responses of said voice information;

a vector quantization table for storing a list of codewords associated prototypical frequency responses; and

a codeword designator for selecting optimal codewords from said list of codewords whose frequency response best matches said frequency response of said voice information; and

a recognizer engine for generating said one or more linguistic units from said optimal codewords.

21. The computing device of claim 19, wherein said one or more linguistic units comprises one or more phonemes.

22. A computer readable medium comprising a software program including a first routine for calculating the significance to voice quality of voice information contained in a first packet;

and a second routine for transmitting one or more additional packets to the recipient containing the voice information if the significance of the voice information be above a threshold level;

wherein said first routine comprises the following subroutines;

a first sub-routine for identifying one or more phonemes contained in the voice information;

a second sub-routine for retrieving a value from memory for each identified phoneme representing the significance to voice quality of that phoneme; and

a third sub-routine for setting the measure of significance for the voice information to the maximum of the values for all of the phonemes contained in the voice information.

23. The computer readable medium of claim 22, wherein the first sub-routine identifies the phonemes in the voice information by implementing a hidden Markov model speech recognition system.

24. The computer readable medium of claim 22, wherein further including a routine for delaying the transmission of said one or more additional packets containing said voice information after said first packet has been transmitted.