Compressing and using a concatenative speech database in text-to-speech systems

• US 7,035,794 B2
• Filed: 03/30/2001
• Issued: 04/25/2006
• Est. Priority Date: 03/30/2001
• Status: Expired due to Fees

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Sirivara, Sudheer
• Primary Examiner(s): Young, W. R.
• Assistant Examiner(s): Vo, Huyen X.
• Application Number:
  US09/822,547
• Publication Number:
  US 20020143543A1
• Time in Patent Office: 1,852 Days
• Field of Search: 704/260, 704/267, 704/258, 704/219, 704/262
• US Class Current: 704/219
• CPC Class Codes: G10L 13/06 Elementary speech units used in speech synthesisers; Concatenation rules
• CPC Class Codes: G10L 19/06 Determination or coding of the spectral characteristics, e.g. of the short-term prediction coefficients

Abstract

A method and apparatus are provided for compressing and using a concatenative speech database in TTS systems to improve the quality of speech output generated by handheld TTS systems by allowing synthesis to occur on the client. According to one embodiment of the present invention, a G.723 encoder receives diphone waveforms, and compresses them into diphone residuals. While compressing the diphone waveforms, the encoder generates Linear Predictive Coding (LPC) coefficients. The diphone residuals, and the encoder-generated LPC coefficients are then stored in encoder-generated compressed packet.

Claims

1. A method, comprising:

receiving input text at a client device;

analyzing the input text to determine diphones;

sending a request to a server for diphone waveform data based on the determined diphones;

locating the requested diphone waveform data by searching a concatenative diphone waveform database at the server;

generating a set of compressed diphone residuals and Linear Predictive Coding (LPC) coefficients by compressing results of the searched diphone waveform database;

storing the set of compressed diphone residuals and the LPC coefficients in a compressed packet;

transmitting the compressed packet to the client device; and

upon receiving the compressed packet, the client device decompresses the compressed packet back to diphone waveform data available for use in a text-to-speech synthesizer.

2. The method of claim 1, wherein the generating of the set of compressed diphone residuals is performed using an encoder.

3. The method of claim 1, further comprising receiving the request from the text-to-speech synthesizer, the text-to-speech synthesizer residing at the client device.

4. The method of claim 1, further comprising providing pitch marks to the text-to-speech synthesizer.

5. The method of claim 2, wherein the encoder comprises a G.723 encoder.

6. A system comprising:

a sever;

a client device coupled the sever, the client device to

receive input text,

analyze the input text to determine diphones, and

send a request to the server for diphone waveform data based on the determined diphones;

the server to

locate diphone waveform data by searching a concatenative diphone waveform database,

generate a set of compressed diphone residuals and Linear Predictive Coding (LPC) coefficients by compressed diphone residuals and the LPC coeffients in a compressed packet, and

transmit the compressed packet to the client device; and

the client device to decompress the compressed packet back to diphone waveform data available for use in a text-to-speech synthesizer.

7. The system of claim 6, wherein the server is further to generate the set of compressed diphone residuals using an encoder, the encoder including a G.723 encoder.

8. The system of claim 6, wherein the server is further to provide pitch marks to the text-to-speech synthesizer at the client device.

9. The system of claim 8, wherein the text-to-speech synthesizer at the client is further to receive the pitch marks.

10. The system of claim 6, wherein the client device comprises a handheld device including one or more of the following:

a telephone, a pocket computer system, and a personal digital assistant (PDA).

11. A machine-readable medium having stored thereon data comprising sets of instructions which, when executed by a machine, cause the machine to:

receive input text at a client device;

analyze the input text to determine diphones;

send a request to a server for diphone waveform data based on the determined diphones;

locate the requested diphone waveform data by searching a concatenative diphone waveform database at the server;

generate a set of compressed diphone residuals and Linear Predictive Coding (LPC) coefficients by compressing results of the searched diphone waveform database;

store the set of compressed diphone residuals and LPC coefficients in a compressed packet;

transmit the compressed packet to the client device; and

upon receiving the compressed packet, the client device decompresses the compressed packet back to diphone waveform data available for use in a text-to-speech synthesizer.

12. The machine-readable medium of claim 11, wherein the generating of the set of compressed diphone residuals is performed using an encoder.

13. The method of claim 11, wherein the sets of instructions which, when executed by the machine, further cause the machine to receive the request from the text-to-speech synthesizer, the text-to-speech synthesizer residing at the client device.

14. The machine-readable medium of claim 11, wherein the sets of instructions which, when executed by the machine, further cause the machine to provide pitch marks to the text-to-speech synthesizer.