Method and system for producing speech signals

• US 6,047,255 A
• Filed: 12/04/1997
• Issued: 04/04/2000
• Est. Priority Date: 12/04/1997
• Status: Expired due to Fees

• Current Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Original Assignee: Nortel Networks Corporation
• Inventors: Williamson, Robert Alan
• Primary Examiner(s): Hudspeth, David R.
• Assistant Examiner(s): SAX, ROBERT L
• Application Number:
  US08/985,058
• Time in Patent Office: 852 Days
• Field of Search: 704/212, 704/267, 704/275
• US Class Current: 704/212
• CPC Class Codes: G10L 13/04 Details of speech synthesis systems, e.g. synthesiser structure or memory management

Abstract

A method and system for producing speech signals is disclosed. The speech signals are produced by sequentially reproducing a series of stored speech signal segments. The speech signals may be used to generate a voice message. The signals are formed by reproducing signal segments for system announcement messages and beginning, end and word-pair fragments for "key" words. The system announcement messages and "key" words define a dictionary for the system. The signal segments for word pair fragments correspond to the end portion of one word, a transition to another word and a beginning portion of that other word. The transition between sequentially produced "key" words in a voice message generated from a signal produced from word pair fragments is audibly smooth. The resulting speech signal may correspond to any sequences of words from the dictionary. The method and system are suited for telephony applications, such as voice mail or directory assistance applications.

Claims

1. A method of storing speech signal segments for generating voice messages containing words in a dictionary of n words, said method comprising the steps of

a. storing n beginning speech signal segments, each beginning segment for generating a beginning portion of a unique word in said dictionary;

b. storing n end speech signal segments, each end segment for generating an end portion of a unique word in said dictionary;

c. storing n×

n middle speech signal segments, each middle segment corresponding to a unique word pair in said dictionary, each middle segment for generating an end portion of an initial word in said pair, a smooth transition to a final word in said pair; and

a beginning portion of said final word;

wherein a signal for generating a voice message containing any first and second words in said dictionary may be generated from a selected one of said n beginning speech signal segments;

a selected one of said n×

n middle speech signal segments; and

a selected one of said n end speech signal segments.

2. The method of claim 1, wherein a signal for generating a voice message containing any word in said dictionary may be produced from a beginning segment and a corresponding end segment.

3. A speech signal storage device for use in generating voice messages containing words in a dictionary having n word entries, said device comprising:

n first memory portions, each storing a signal segment for generating a beginning portion of a unique word in said dictionary;

n second memory portions, each storing a signal segment for generating an end portion of a unique word in said dictionary;

n×

n third memory portions, each storing a speech signal segment corresponding to a unique word pair in said dictionary and for generating an end portion of an initial word in said pair, a smooth transition to a final word in said pair, and a beginning portion of said final word

wherein any first and second word in said dictionary may be generated from a signal segment selected from one of said first memory portions;

a signal segment selected from one of said third memory portions; and

a signal segment selected from one of said second memory portions.

4. The device of claim 3, wherein a voice message containing any word in said dictionary may be generated from a signal segment stored in a first memory portion and a complementary signal segment stored in a second memory portion.

5. A system for producing a speech signal for generating a voice message comprising words in a dictionary having n words, said system comprising:

a processor;

a memory device interconnected to said processor;

said memory device comprising;

n first memory portions each storing a signal segment for generating a beginning portion of a unique word in said dictionary;

n second memory portions each storing a signal segment for generating an end portion of a unique word in said dictionary;

n×

n third memory portions, each storing a signal segment corresponding to a unique word pair in said dictionary and for generating an end portion of an initial word in said pair, a smooth transition to a final word in said pair, and a beginning portion of said final word;

an output device connected to said processor;

wherein said processor is adapted to select and provide said output device signal segments selected from said first, second and third memory portions to produce said speech signal and wherein any first and second word in said dictionary may be generated from a signal segment selected from one of said first memory portions;

a signal segment selected from one of said third memory portions; and

a signal segment selected from one of said second memory portions.

6. The system of claim 5, further comprising an input device interconnected to said processor, said input device adapted to receive and provide commands to said processor to produce speech signals at said output device.

7. The system of claim 5, further comprising a plurality of fourth memory portions, each fourth memory portion storing a speech signal segment for generating a system announcement message.

8. The system of claim 6, wherein said output device comprises a digital to analog converter.

9. A system for producing a speech signal for generating a voice message containing words and phrases in a dictionary, said dictionary comprising a plurality of system announcement messages and n key words, said system comprising:

a processor;

a memory device interconnected to said processor;

said memory device comprising;

n first memory portions each storing a signal segment for generating a beginning portion of a different word in said dictionary;

n second memory portions each storing a signal segment for generating an end portion of a different word in said dictionary;

n×

n third memory portions, each storing a speech signal segment corresponding to a unique word pair in said dictionary and for generating an end portion of an initial word in said pair, a smooth transition to a final word in said pair, and a beginning portion of said final word;

a plurality of fourth memory portions, each storing a speech signal segment for generating one of said system announcement messages;

an output device interconnected with said processor;

wherein said processor is adapted to select and provide said output device sequential signal segments selected from said first, second and third memory portions, and a speech signal segment selected from said fourth memory portions to produce said speech signal.

10. A speech signal storage device for use in producing speech signals for generating a voice message containing words from a dictionary having at least n word entries, said device comprising:

n×

n memory portions, each storing a speech signal segment corresponding to a unique word pair in said dictionary and for generating an end portion of an initial word in said pair, a smooth transition to a final word in said pair and a beginning portion of said final word;

whereby a signal for generating a sequence of words from said dictionary may be produced from signal segments sequentially reproduced from said n×

n memory portions.

11. A speech signal storage device for use in generating voice messages containing words in a dictionary having n word entries, said device comprising:

n first memory portions, each storing a signal segment for generating a beginning portion of a unique word in said dictionary;

n second memory portions, each storing a signal segment for generating an end portion of a unique word in said dictionary;

n×

n third memory portions, each storing a speech signal segment corresponding to a unique word pair in said dictionary and for generating an end portion of an initial word in said pair, a smooth transition to a final word in said pair, and a beginning portion of said final word.

12. A computer program stored on a computer readable medium, said computer program, loadable into memory of a computer having a processor, and an output device interconnected with said processor,

said program when loaded into said memory forming

n first memory portions each storing a signal segment for generating a beginning portion of a different word in a dictionary having n word entries;

n second memory portions each storing a signal segment for generating an end portion of a different word in said dictionary;

n×

n third memory portions, each storing a speech signal segment corresponding to a unique word pair in said dictionary and for generating an end portion of an initial word in said pair, a smooth transition to a final word in said pair, and a beginning portion of said final word;

said program adapting said processor

to select and provide said output device sequential signal segments selected from said first, second and third memory portions to produce a speech signal containing words in said dictionary, wherein any first and second word in said dictionary may be generated from a signal segment selected from one of said first memory portions a signal segment selected from one of said third memory portions; and

a signal segment selected from one of said second memory portions.