Voice data processing method and device

• US 20070088540A1
• Filed: 01/26/2006
• Published: 04/19/2007
• Est. Priority Date: 10/19/2005
• Status: Abandoned Application

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Hirakawa, Kazunari, Ohta, Toshiyuki, Nomoto, Kazuhiro, Asada, Kano
• Application Number:
  US11/341,563
• Publication Number:
  US 20070088540A1
• Time in Patent Office: Days
• US Class Current: 704/216
• CPC Class Codes: G10L 19/005 Correction of errors induced by the transmission channel, if related to the coding algorithm
• CPC Class Codes: G10L 19/09 Long term prediction, i.e. removing periodical redundancies, e.g. by using adaptive codebook or pitch predictor

Abstract

In a voice data processing method and device detecting a pitch from history data during a packet loss and generating compensating data thereof, input signal data is decoded in a normal mode, a calculation of a normalized cross-correlation in coarse search used for a pitch detection is repeated by a predetermined frequency of loops within a required frequency of loops, based on history decode data, a peak value of a normalized cross-correlation obtained by the calculation and a delay data value corresponding thereto are held, and fine search is executed by repeating the calculation of the normalized cross-correlation in the coarse search by a remaining required frequency of loops, by using the peak value of the normalized cross-correlation and the delay data value in a packet loss mode, thereby generating compensating data.

Claims

1. A voice data processing method comprising:

a first step of, in a normal mode, decoding input signal data, repeating a calculation in coarse search used for a pitch detection by a predetermined frequency of loops within a required frequency of loops, based on history decode data, and holding a peak value of a normalized cross-correlation obtained by the calculation and a delay data value corresponding thereto; and

a second step of, in a packet loss mode, executing the pitch detection by repeating a calculation of a normalized cross-correlation in the coarse search by a remaining required frequency of loops, by using the peak value of the normalized cross-correlation and the delay data value, thereby generating compensating data.

2. The voice data processing method as claimed in claim 1, wherein the first and the second step respectively include a third and a fourth step of determining whether or not the input signal data is silence signal data, and of invalidating the coarse search when the input signal data is determined to be the silence signal data.

3. The voice data processing method as claimed in claim 2, wherein the first and the second step respectively include a fifth and a sixth step of invalidating and validating the third and the fourth step respectively when the predetermined frequency of loops is a first value corresponding to a suppression request of a coarse search amount in the normal mode, and of contrarily validating and invalidating the third and the fourth step when the predetermined frequency of loops is a second value corresponding to a suppression request of a coarse search amount in the packet loss mode.

4. The voice data processing method as claimed in claim 1, wherein the required frequency of loops corresponds to a number of samples from a maximum delay pitch to a minimum delay pitch for a reference signal.

5. A voice data processing device comprising:

a first means, in a normal mode, decoding input signal data, repeating a calculation in coarse search used for a pitch detection by a predetermined frequency of loops within a required frequency of loops, based on history decode data, and holding a peak value of a normalized cross-correlation obtained by the calculation and a delay data value corresponding thereto; and

a second means, in a packet loss mode, executing the pitch detection by repeating a calculation of a normalized cross-correlation in the coarse search by a remaining required frequency of loops, by using the peak value of the normalized cross-correlation and the delay data value, thereby generating compensating data.

6. The voice data processing device as claimed in claim 5, wherein the first and the second means respectively include a third and a fourth means determining whether or not the input signal data is silence signal data, and of invalidating the coarse search when the input signal data is determined to be the silence signal data.

7. The voice data processing device as claimed in claim 6, wherein the first and the second means respectively include a fifth and a sixth means invalidating and validating the third and the fourth means respectively when the predetermined frequency of loops is a first value corresponding to a suppression request of a coarse search amount in the normal mode, and of contrarily validating and invalidating the third and the fourth means when the predetermined frequency of loops is a second value corresponding to a suppression request of a coarse search amount in the packet loss mode.

8. The voice data processing device as claimed in claim 5, wherein the required frequency of loops corresponds to a number of samples from a maximum delay pitch to a minimum delay pitch for a reference signal.