1. A method for computer-assisted stylization of an image implemented by at least one computing device, the method comprising: creating, by the at least one computing device, a source image and a target image each comprising a multi-channel image that includes at least a style channel and multiple light path expression (LPE) channels having light propagation information; and synthesizing, by the at least one computing device, the style channel of the target image to mimic a stylization of individual illumination effects from the style channel of the source image, the synthesizing including at least: guiding the synthesizing of the style channel of the target image based on the light propagation information; transferring the stylization of individual illumination effects from the style channel of the source image to the style channel of the target image based on the guiding of the light propagation information; and generating the style channel of the target image, based on the transferring of the stylization of individual illumination effects, for display of the target image via a display device; and further comprising: calculating, by the at least one computing device, matching errors of potential source-to-target patch assignments between the source image and the target image; determining, by the at least one computing device, an error budget based on a curve fitted to the matching errors; and assigning, by the at least one computing device, patches from the style channel of the source image to the style channel of the target image based on the error budget.