1. An image tone adjustment method, performed by a computer having computer-readable instructions stored therein, such that the computer-readable instructions configure the computer to perform the method, comprising: fitting, by an image tone adjustment apparatus, an overlapping area between a target image and a first image to obtain a first correction parameter, and fitting an overlapping area between the target image and a second image to obtain a second correction parameter, wherein a portion of the target image at a first side overlaps with the first image, and a portion of the target image at a second side overlaps with the second image; performing interpolation, by the image tone adjustment apparatus, on each pixel of the target image according to the first correction parameter and the second correction parameter to obtain a corresponding correction parameter, and correcting the target image according to the corresponding correction parameters; fitting, by the image tone adjustment apparatus, an overlapping area between the corrected target image and the first image to obtain a first RGB three-channel linear transformation parameter, and fitting an overlapping area between the corrected target image and the second image to obtain a second RGB three-channel linear transformation parameter, wherein for RGB, R is red, G is green, and B is blue; and performing linear interpolation, by the image tone adjustment apparatus, on each pixel of the corrected target image according to the first RGB three-channel linear transformation parameter and the second RGB three-channel linear transformation parameter, to obtain a corresponding RGB three-channel linear transformation parameter, and transforming the corrected target image according to the corresponding RGB three-channel linear transformation parameters.