29P-A-7 U字型曲線をつないだ音声波モデル(人間の感覚と損傷に対する生物工学的アプローチ(2),一般講演)

概要

論文の詳細を見る
Because a series of spikes in the auditory nerves are phase-locked to the appearance of either maxima or minima, the recording of extrema plays an important role in the succeeding extraction process. Approximate twenty percent of extrema, for instance, could be reduced in the previous study according to the forward masking, which demonstrates the short-term (< 3ms) inaudible period between envelope maxima in a narrow-bandwidth waveform. Further extraction as well as the simplified modeling of acoustic structure, however, remains unresolved, still yielding a large number of extrema with minute energy or amplitude. In this study, each amplitude envelope is approximated by a kernel function, which consists of a short series of extrema. After setting a limen in line with both subjective scores and intelligibility of speech syntheses, we deleted every kernel function below the limen, extrema between envelope maxima, and all the minima besides. Consequently, the reduction in total has reached over seventy-five percent, so that we have proposed the modified model, in which a kernel can be reconstructed by the linkage of one term of sinusoidal curves with either linearly increased or decreased amplitude, instead of a half term of sinusoids.
2011-10-29