Watermark superposition and recovery method and device

The embodiment of the invention provides a watermark superposition and recovery method and device, is applied to the technical field of information, and can identify the pixel feature of each pixel point in a to-be-processed image; calculating a target index value according to the identified pixel features of each pixel point; determining a target superposition position corresponding to the target index value according to the target index value and a corresponding relation between a predetermined index value and a superposition position; and according to the to-be-superposed watermark information, modifying the pixel of the target superposition position to obtain a superposed image. The corresponding relation between the index value and the superposition position is preset, and then the target index value is calculated according to the pixel feature of each pixel point in the to-be-processed image, so that the target superposition position corresponding to the target index value is determined, the watermark s