| 摘要 |
The present invention contains three methods for quickly deducing the fundamental frequency of a complex wave form or signal. One method uses the relationships between and among the frequencies of higher harmonics including ratios of frequencies, differences between frequencies, ratios of frequency differences, and relationships stemming from the fact that harmonic frequencies are modeled by functions of an integer variable whose values represent harmonic ranking numbers. Another method depicts the predicted/modeled relationships of the harmonics of selected frequency registers on logarithmic scales, records the frequencies of detected partials on like scales, and moves the scales with respect to each other searching for a match of three harmonics. When such a match is found, possible harmonic ranking numbers and the implied fundamental frequency can be extracted directly. When the detected partials match more that one set of predicted/modeled harmonic relationships, algorithms of the first method are used to select the deduced fundamental. By still another method, harmonic frequencies for a plurality of fundamentals are amassed and organized so that partials linked to an unknown fundamental can be compared with them and the unknown fundamental deduced.
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