The invention discloses a lightweight interpretable image shadow removal model based on an image reconstruction theory, which adopts a three-stage progressive network, in a stage I, an original image and a corresponding
shadow mask image are received as input, a
degradation process of a shadow region is learned through a
gradient descent module, and a reconstruction result is sent to a near-end mapping module; the near-end mapping module completes the shadow removal work of the first stage under the supervision of the
shadow mask graph to obtain a shadow-free graph; the second stage is the same as the first stage, and only the shadow-free image in the first stage is used as input; and a third stage of receiving the shadow-free image and the
shadow mask image from the second stage, sending the shadow-free image and the shadow
mask image to a space detail retention module after passing through a
gradient descent module, and introducing the original image containing the shadow and the corresponding shadow
mask image by the space detail retention module to adjust image details so as to obtain a final shadow-removed image. According to the method, the shadow removal effect is improved while the model is ensured to have relatively good
interpretability, and the model is subjected to lightweight design to adapt to more practical application scenes.