Pattern spot extraction method and device

The invention discloses a pattern spot extraction method and device. The method comprises the following steps: carrying out spatial overlapping intersection analysis on a permanent basic farmland layer and a public welfare forest layer to obtain a first layer, wherein the first layer indicates all overlapping pattern spots of the permanent basic farmland layer and the public welfare forest layer at spatial positions; and calculating the shape and the area of each overlapping pattern spot, the contained land type regions and the area proportions of the various land type regions; determining screening factors of the overlapped pattern spots, wherein the screening factors comprise shapes, areas, land type regions and area proportions of the land type regions; and according to a preset constraint condition, selecting a target overlapping pattern spot, and screening the overlapping pattern spot of which the factor meets the constraint condition as the target overlapping pattern spot. Visibly, according to the embo