The invention discloses an unmanned aerial vehicle
aerial image dense
crowd counting and grade classification method based on a multilayer CNN, and the method comprises the following steps: carrying out the
standardization preprocessing of an input unmanned aerial vehicle
aerial image I; multi-scale features of the image are extracted through multi-layer
convolution and
pooling operation, and a high-level
semantic feature map F is obtained; a context aggregation module is utilized, adaptive average
pooling of different scales is adopted to capture global to local context information, and a feature map F'with attention weight is generated through
convolution fusion; a rear-end decoder recovers spatial details by using cavity
convolution, a single-
channel density map D is output through convolution operation, and a
crowd counting result is obtained through integration; and finally, based on the density map D, dividing four density intervals through a threshold value: analyzing and marking a region above
medium density by using 8 connected domains, and outputting a
visualization result on the image I. According to the invention, grading and counting of
crowd density in an unmanned aerial vehicle aerial photographing scene can be accurately realized, and applications such as public
safety monitoring and large-scale
activity management can be effectively supported.