| 摘要 |
The invention relates to a method of detection of objects, preferably fish, from sonar data. Echo signals from repeated sonar measurements are digitised and registered in a two-dimensional data presentation where echo distance, alternatively the duration of the signal, constitutes one dimension, and the measurement number, alternatively the time of measurement, constitutes the other dimension. Once the desired size of the data presentation is obtained, two-dimensional filtration, adaptive thresholding and morphological processing are carried out to enable an echogram having less noise and more reliable detection of desired objects to be produced. Additional shape analysis further enhances the detection. |
