A computer-implemented method for generating a background-free image, comprising: determining (S1 10) an image proportion of a target subject in an original image by: performing saliency detection on the original image to obtain an initial mask of the original image; binarizing the initial mask of the original image to obtain a binarized mask of the original image; and computing the image proportion of the target subject in the original image based on an area of a target subject region in the binarized mask of the original image and an area of the original image; clipping, in response to the image proportion being less than a preset threshold, a subject region image corresponding to the target subject from the original image by: determining a smallest bounding matrix of the target subject based on the binarized mask of the original image; enlarging an image region corresponding to the smallest bounding matrix to a preset multiple, for use as a clipped image region; and clipping a corresponding image block from the original image based on a position of the clipped image region, for use as the subject region image; determining a corresponding subject region mask based on the subject region image; and synthesizing the subject region mask and the subject region image to generate a background-free image corresponding to the original image; wherein after the computing the image proportion of the target subject in the original image based on an area of a target subject region in the binarized mask of the original image and an area of the original image, the method further comprises: generating a tripartite image based on the binarized mask of the original image in response to the image proportion being more than or equal to the preset threshold, and matting the original image using a preset matting algorithm based on the tripartite image, to obtain a final mask of the original image; and synthesizing the final mask of the original image and the original image to generate the background-free image corresponding to the original image. determining (S1 10) an image proportion of a target subject in an original image by: performing saliency detection on the original image to obtain an initial mask of the original image; binarizing the initial mask of the original image to obtain a binarized mask of the original image; and computing the image proportion of the target subject in the original image based on an area of a target subject region in the binarized mask of the original image and an area of the original image; clipping, in response to the image proportion being less than a preset threshold, a subject region image corresponding to the target subject from the original image by: determining a smallest bounding matrix of the target subject based on the binarized mask of the original image; enlarging an image region corresponding to the smallest bounding matrix to a preset multiple, for use as a clipped image region; and clipping a corresponding image block from the original image based on a position of the clipped image region, for use as the subject region image; determining a corresponding subject region mask based on the subject region image; and synthesizing the subject region mask and the subject region image to generate a background-free image corresponding to the original image; wherein after the computing the image proportion of the target subject in the original image based on an area of a target subject region in the binarized mask of the original image and an area of the original image, the method further comprises: generating a tripartite image based on the binarized mask of the original image in response to the image proportion being more than or equal to the preset threshold, and matting the original image using a preset matting algorithm based on the tripartite image, to obtain a final mask of the original image; and synthesizing the final mask of the original image and the original image to generate the background-free image corresponding to the original image. generating a tripartite image based on the binarized mask of the original image in response to the image proportion being more than or equal to the preset threshold, and matting the original image using a preset matting algorithm based on the tripartite image, to obtain a final mask of the original image; and synthesizing the final mask of the original image and the original image to generate the background-free image corresponding to the original image.