Image background recognition method, image background replacement system, memory and device

The invention relates to the technical field of image processing, and discloses an image background recognition method, which comprises the following steps of: converting an image into a YUV color space; establishing a coordinate system taking the Cb value and the Cr value as coordinates, and setting a color gamut range in the coordinate system; extracting a Cb value and a Cr value of each pixel point in the image; determining a coordinate point, represented in the coordinate system, of each pixel point by using a Cb value and a Cr value; and comparing the coordinate point with the color gamut range, if the coordinate point is located in the color gamut range, determining that a pixel point corresponding to the coordinate point is located in the background of the image, and extracting position information of the pixel point in the image. The invention also discloses an image background replacement system, a memory and a device. The invention aims to solve the problems of poor background replacement real-time performance, stiff edge and uncontrollable and adjustable replacement effect in the prior art.