The invention relates to the technical field of
algal bloom automatic identification, and discloses an
algal bloom automatic identification method and
system based on multispectral information, and the method comprises the steps: firstly carrying out the
standardization processing and mosaic fusion of an original
multispectral image, and obtaining high-quality
reflectivity data; and then, by calculating a
water body-
vegetation absorption index and performing intelligent extraction, a
water body range is accurately defined, and non-
water body interference is eliminated. The potential
algal bloom area in the water body is subjected to self-adaptive preliminary screening through the
band ratio index, the classification range is narrowed, and the efficiency is improved. And finally, extracting multi-dimensional feature vectors including spectral
reflectivity, waveband ratio index, yellowness index and reflection valley depth from the potential algal bloom areas, and inputting the multi-dimensional feature vectors into a pre-trained
machine learning classifier model for
deep learning and
pattern recognition. Therefore, the limitation that a traditional method only depends on a single or few empirical indexes is overcome, more complex and fine spectral characteristics of
algae blooms can be captured, and high-precision classification and discrimination are achieved.