According to a computer-implemented method for generating a reference image for testing an electronic vehicle guidance system, an input image (1) representing a scene in an environment of a vehicle is received, a depth image (2) of the scene is computed by applying a depth estimation algorithm to the two-dimensional input image, a surface map (6) of the scene, which depicts a surface representation of the scene lit by at least one virtual light source, is computed depending on the depth image (2) and depending on a predefined set of light source parameters (5) of the at least one virtual light source, and the reference image is computed depending on a weighted combination (7) of the surface map (6) with the input image (1).