| 主权项 |
1. An ultrasound observation apparatus for generating an ultrasound image based on an ultrasound signal obtained by an ultrasound probe, the ultrasound probe having an ultrasound transducer for transmitting an ultrasound wave to an observation target and receiving the ultrasound wave reflected from the observation target, the ultrasound observation apparatus comprising:
a frequency analysis unit configured to analyze a frequency of the ultrasound signal to calculate a plurality of frequency spectra depending on a reception depth and a reception direction of the ultrasound signal; a frequency band setting unit configured to set a frequency band used for calculating a feature of each of the frequency spectra calculated by the frequency analysis unit by use of parameters associated with a frequency spectrum in each of a plurality of candidate bands having different bandwidths; a feature calculation. unit configured to calculate the feature of each of the frequency spectra based on the frequency band set by the frequency band setting unit; and a feature image data generation unit configured to generate feature image data for displaying information on the feature calculated by the feature calculation unit, wherein the frequency band setting unit comprises: an envelope curve detection, unit configured to detect an envelope curve of each of the frequency spectra; a parameter extraction unit configured to extract the parameters in the plurality of candidate bands, respectively, the parameters being associated with an approximate line obtained by approximating the envelope curve; a variation calculation unit configured to calculate a variation between two parameters respectively extracted in two candidate bands of the plurality of candidate bands having a predetermined relationship, among the parameters extracted per candidate band by the parameter extraction unit; and a determination unit configured to determine the frequency band based on the variation calculated by the variation calculation unit. |
