Apparatus and method for calculating a fundamental frequency change
AssigneeKabushiki Kaisha Toshiba
InventorsYusuke Kida, Takashi Masuko
Life of this patent
Estimating the term…
Abstract
A logarithmic frequency spectrum within a predetermined time range is calculated from a speech signal. The logarithmic frequency spectrum has a frequency element at equal intervals along a logarithmic frequency axis. A logarithmic frequency spectrogram is calculated by connecting a plurality of logarithmic frequency spectrums. A value of the frequency element along a straight line on the logarithmic frequency spectrogram is voted onto a Hough plane. The Hough plane has a voted value in correspondence with a gradient of the straight line. The voted value above a threshold and the gradient corresponding to the voted value are extracted from the Hough plane. A fundamental frequency change is calculated using the voted value and the gradient extracted.
Claims9
An apparatus for calculating a fundamental frequency change, comprising:
- a spectrogram calculation unit configured to calculate a logarithmic frequency spectrum by analyzing a frequency of a frame having a predetermined time range divided from a speech signal, the logarithmic frequency spectrum having a frequency element at equal intervals along a logarithmic frequency axis, and to calculate a logarithmic frequency spectrogram by connecting a plurality of logarithmic frequency spectrums of frames adjacent along a time axis;
- a Hough transform unit configured to vote a value of the frequency element along a straight line on the logarithmic frequency spectrogram onto a Hough plane, the Hough plane having a voted value in correspondence with a gradient of the straight line;
- an extraction unit configured to extract the voted value larger than a threshold and the gradient corresponding to the voted value from the Hough plane;
- and
- a change calculation unit configured to calculate a fundamental frequency change using the voted value and the gradient extracted.
A method for calculating a fundamental frequency change, comprising:
- calculating a logarithmic frequency spectrum by analyzing a frequency of a frame having a predetermined time range divided from a speech signal, the logarithmic frequency spectrum having a frequency element at equal intervals along a logarithmic frequency axis;
- calculating a logarithmic frequency spectrogram by connecting a plurality of logarithmic frequency spectrums of frames adjacent along a time axis;
- voting a value of the frequency element along a straight line on the logarithmic frequency spectrogram onto a Hough plane, the Hough plane having a voted value in correspondence with a gradient of the straight line;
- extracting the voted value larger than a threshold and the gradient corresponding to the voted value from the Hough plane;
- and
- calculating a fundamental frequency change using the voted value and the gradient extracted.
A non-transitory computer-readable medium storing program codes for causing a computer to calculate a fundamental frequency change, the program codes comprising:
- a first program code to calculate a logarithmic frequency spectrum by analyzing a frequency of a frame having a predetermined time range divided from a speech signal, the logarithmic frequency spectrum having a frequency element at equal intervals along a logarithmic frequency axis;
- a second program code to calculate a logarithmic frequency spectrogram by connecting a plurality of logarithmic frequency spectrums of frames adjacent along a time axis;
- a third program code to vote a value of the frequency element along a straight line on the logarithmic frequency spectrogram onto a Hough plane, the Hough plane having a voted value in correspondence with a gradient of the straight line;
- a fourth program code to extract the voted value larger than a threshold and the gradient corresponding to the voted value from the Hough plane;
- and
- a fifth program code to calculate a fundamental frequency change using the voted value and the gradient extracted.
Dependencies are inferred from the claim text.