The present disclosure provides a method for processing a video signal through target modification, the method comprising the steps of: acquiring a target modification flag from a sequence parameter set of the video signal, wherein the target modification flag indicates whether a modification is performed on a target region; if the modification is performed on the target region according to the target modification flag, acquiring a target modification index, wherein the target modification index indicates a target modification scheme which corresponds to a non-modification, a left-right symmetric modification, an up-down symmetric modification, a rotation modification, or a combination thereof; identifying a target modification scheme which corresponds to the target modification index; and performing an inverse-modification on a reconstructed target region, according to the identified target modification scheme.