Method of composing messages for speech output

• US 20020029139A1
• Filed: 06/28/2001
• Published: 03/07/2002
• Est. Priority Date: 06/30/2000
• Status: Active Grant

• Current Assignee: novero GmbH (Laird Limited)
• Original Assignee: Nokia Corporation
• Inventors: Theimer, Wolfgang, Buth, Peter, Grothues, Simona, Iman, Amir
• Granted Patent: US 6,757,653 B2
• Time in Patent Office: Days
• US Class Current: 704/201
• CPC Class Codes: G10L 13/07 Concatenation rules

Abstract

The invention concerns a method of composing messages for speech output, in particular the improvement of the quality of reproduction of speech outputs of this kind. For this purpose a series of original sentences for messages is segmented. These segments (10) are stored in the form of audio files together with search criteria in a database (11). Additionally to this information further entries (12) are made on the segments (10), in that the length, the position and the transition values for the respective segments (10) are recorded and stored. If a sentence is to be reproduced it is transmitted in a format corresponding to the format of the search criteria. Then an investigation is done into whether the sentence to be reproduced can be fully reproduced by one segment or by a succession of stored segments (10). If this is the case the segments found in each case are examined using their entries (12) as to how far the individual segments match as regards speech rhythm, wherein the audio files of the segments (10) in which the examination resulted in the pre-requisites for optimal maintaining of the natural speech rhythm are then combined and output for reproduction.

Claims

1. Method of composing messages for speech output consisting of segments (10) of at least one original sentence, which are stored as audio files, in which a message intended for output is composed from the segments (10) stored as audio files, selected using search criteria from the stored audio files, characterised in that each segment (10) is allocated at least one parameter (12) characterising its phonetic properties in the original sentence and using the parameters (12) of the individual segments (10) characterising the phonetic properties in the original sentence a check is made as to whether the segments (10) forming the reproduction sentence to be output as a message are composed according to their natural flow of speech.

2. Method according to claim 1, characterised in that each segment (10) is allocated several parameters (12) characterising its phonetic properties in the original sentence.

3. Method according to claim 1, characterised in that as the parameters (12) characterising the phonetic properties of the segments (10) in the respective original sentence at least one of the following parameters is used:

length (L) of the respective segment (10)

position (P) of the respective segment (10) in the original sentence

front and/or rear transition value (U) of the respective segment (10) to the preceding or following segment (10) in the original sentence.

4. Method according to claim 3, characterised in that the length of the search criterion allocated in each case is used as the length (L) of the respective segment.

5. Method according to claim 3, characterised in that the last or first letters, syllables or phonemes of the preceding or following segment (10) in the original sentence are used as transition values (Ü

).

6. Method according to claim 1, characterised in that as a further parameter (12) data are provided on whether the respective segment (10) of the original sentence is derived from a question or exclamation sentence.

7. Method according to claim 1, characterised in that for a found combination of segments (10) forming the reproduction sentence to be output as a message an evaluation measurement (B) is calculated from the parameters (12) of the individual segments (10) characterising the phonetic properties in the original sentence according to the following formula:

8. Method according to claim 7, characterised in that for each found combination of segments (10) forming the reproduction sentence to be output as a message, an evaluation measurement (B) is calculated and from the found combinations of segments (10) those whose evaluation measurement (B) indicates that the segments (10) of the combination are composed according to a natural flow of speech are selected as the message to be reproduced.

9. Method according to claim 7, characterised in that the evaluation measurement (B) is calculated from the functional correlations f_n(n) of at least the following parameters, length (L) and position (P), as well as the front and rear transition value (Ü

_vorn, Ü

_hinten) of the segment (10) according to the following formula;

10. Method according to claim 1, characterised in that the reproduction sentence is in a format corresponding to the search criteria, wherein preferably alphanumeric character strings are used for the search criteria and the transmitted reproduction sentences.

11. Method according to claim 1, characterised in that the search criteria are arranged hierarchically in a database (11).

12. Method according to claim 1, characterised in that

for selection of the segments (10) for a message stored as audio files a test is done as to whether the reproduction sentence desired as a message coincides in its entirety with a search criterion filed in a database (11) together with an allocated audio file, wherein, if this is not the case, the end of the respective reproduction sentence is reduced and then checked for consistencies with search criteria filed in the database (11) until one or more consistencies have been found for the remaining part of the reproduction sentence,

the checking mentioned in the last paragraph is continued for those parts of the reproduction sentence which were removed in a preceding step

a check is done for each combination of segments (10) whose search criteria fully coincide with the reproduction sentence as to whether the segments (10) forming the reproduction sentence to be output as a message are composed according to their natural flow of speech and

for the reproduction of a desired message the audio files of the segments (10) are used whose combination comes closest to the natural flow of speech.