| 摘要 |
PURPOSE:To calculate only one side of interpolation and interpolationless linear estimation coefficients by deciding either one of interpolation and interpolationless is performed before calculating the interpolation and interpolationless linear estimation coefficients. CONSTITUTION:A linear estimation analyzer 20 and a sound power instrument 130 perform the fetch of a first frame digital sound signal Sij. Then, the linear estimation analyzer 20 calculates a linear estimation coefficient alpha(i) of a digital input sound. Then, the sound power instrument 130 operates the total sum of the square of the input sound, and operates sound power Pi, and outputs it to a sound power difference operation part 50. The sound power Pi-$1 is fetched from a memory 40 to the operation part 50, and a threshold value E is compared with a difference (epsilon) by a comparison part 70, and interpolation decision, interpolationless decision are performed. Finally, from the result of the preceding step, a linear estimation coefficient correction part 80 corrects the estimation coefficient to the interpolation coefficient alphaI (K, i) or the interpolationless coefficient an (K, i) (0<=i<NS, 0<=i<NP) of a K numbered sub-frame to output. |
