1. A method for bleed-through detection, comprising: obtaining a recto image and a verso image in a double-sided image pair which have been aligned, where for each first point in the recto image, a second point corresponding thereto in the verso image is known, and obtaining pixel pairs including first points and corresponding second points; determining foreground pixels and background pixels in the recto image and the verso image; performing modeling for four types of pixel pairs based on a predetermined feature, on the basis of a result of the determining, to form four models, the four models with the predetermined feature of the four types of pixel pairs comprising: both the first point and the second point are foreground pixels, both the first point and the second point are background pixels, the first point is a foreground pixel and the second point is a background pixel, and the first point is the background pixel and the second point is the foreground pixel; calculating, for an un-modeled pixel pair that has not been modeled, similarities of the pixel pair with respect to the four models respectively, according to the predetermined feature of the pixel pair to determine a type of the un-modeled pixel pair; and judging, as verso bleed-through on the verso image, the second point determined as the background pixel which corresponds to the first point determined as the foreground pixel, and judging, as recto bleed-through on the recto image, the first point determined as the background pixel which corresponds to the second point determined as the foreground pixel.