| 摘要 |
PROBLEM TO BE SOLVED: To simply control the reproducing speed of the voice signal with high quality without changing the phoneme and pitch by transforming N orthogonal transformation coefficient data into M data, inverse-transforming the transformed data, and making prediction synthesis based on the obtained linear/ nonlinear prediction residual. SOLUTION: The linear/nonlinear prediction residual, e.g. short-term prediction residual, is obtained for the input signal, and orthogonal transformation is applied to the obtained short-term prediction residual. N orthogonal transformation coefficient data obtained for each transformation unit are inputted from a transmission signal input terminal 13, and N orthogonal transformation coefficient data are transformed into M orthogonal transformation coefficient data by a data number transformation section 5. M orthogonal transformation coefficient data obtained by the data number transformation section 5 are inverse-transformed by an inverse orthogonal transformation section 6. Prediction synthesis is made by an LPC synthesizing filter 7 based on the short-term prediction residual obtained by the inverse orthogonal transformation section 6. The reproducing speed can be simply controlled. |
