Method of generating a prosodic model for adjusting speech style and apparatus and method of synthesizing conversational speech using the same

• US 20070106514A1
• Filed: 11/07/2006
• Published: 05/10/2007
• Est. Priority Date: 11/08/2005
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: Kim, Sang, Oh, Seung, Lee, Young
• Granted Patent: US 7,792,673 B2
• Time in Patent Office: Days
• US Class Current: 704/260
• CPC Class Codes: G10L 13/033 Voice editing, e.g. manipulating the voice of the synthesiser
• CPC Class Codes: G10L 13/04 Details of speech synthesis systems, e.g. synthesiser structure or memory management

Abstract

An apparatus and method for adjusting the friendliness of a synthesized speech and thus generating synthesized speech of various styles in a speech synthesis system are provided. The method includes the steps of defining at least two friendliness levels; storing recorded speech data of sentences, the sentences being made up according to each of the friendliness levels; extracting at least one of prosodic characteristics for each of the friendliness levels from the recorded speech data, said prosodic characteristics including at least one of a sentence-final intonation type, boundary intonation types of intonation phrases in the sentence, and an average value of F₀ of the sentence, with respect to the recorded speech data; and generating a prosodic model for each of the friendliness levels by statistically modeling the at least one of the prosodic characteristics.

Claims

1. A method of generating a prosodic model for controlling a speech style, comprising the steps of:

defining at least two friendliness levels;

storing recorded speech data of sentences, the sentences being made up according to each of the friendliness levels;

extracting at least one of prosodic characteristics for each of the friendliness levels from the recorded speech data, said prosodic characteristics including at least one of a sentence-final intonation type, boundary intonation types of intonation phrases in the sentence, and an average value of F₀ of the sentence, with respect to the recorded speech data; and

generating a prosodic model for each of the friendliness levels by statistically modeling the at least one of the prosodic characteristics.

2. The method according to claim 1, wherein the prosodic model includes information of speech act and sentence style and prosodic information.

3. The method according to claim 2, wherein the information of speech act and sentence type is “

opening,”

“

request-information,”

“

give-information,”

“

request-action,”

“

propose-action,”

“

expressive”

, “

commit”

, “

call”

, “

acknowledge”

, “

closing”

, “

statement”

, “

command”

, “

wh-question”

, “

yes-no question”

, “

proposition”

or “

exclamation.”

4. The method according to claim 2, wherein the prosodic information includes F₀ value of the sentence and type of sentence-final intonation for each of the friendliness levels.

5. A speech synthesis method for adjusting a speech style, comprising the steps of:

(a) receiving a sentence with a marked friendliness level;

(b) selecting a prosodic model based on the marked friendliness level of the sentence; and

(c) generating a synthesized speech of the sentence with the marked friendliness level by obtaining speech segments from a synthesis unit database on the basis of the selected prosodic model, the synthesis unit database storing speech segments for each friendliness level.

6. The speech synthesis method according to claim 5, wherein the synthesis unit database stores sentence data and the corresponding speech segments recorded according to each friendliness level, the sentence data including information of speech act, a sentence type, or a sentence final verbal-ending or a combination thereof according to each friendliness level.

7. The speech synthesis method according to claim 5, wherein the step (c) includes the steps of:

(c1) extracting the speech segments from the synthesis unit database using prosodic information of the sentence based on the selected prosodic model; and

(c2) synthesizing the extracted speech segments.

8. A speech synthesis apparatus for adjusting a speech style, comprising:

a prosodic model storage for storing prosodic models for each friendliness level, the prosodic models including sentential information and the corresponding prosodic characteristics for each friendliness level;

a synthesis unit database for storing speech segments of each friendliness level; and

a speech generator for selecting the prosodic model based on a marked friendliness level of an input sentence and obtaining the speech segments from the synthesis unit database on the basis of the selected prosodic model to generate a synthesized speech of the input sentence.