Single target portrait-based face portrait compositing method

The invention discloses a single target portrait-based face portrait compositing method. The single target portrait-based face portrait compositing method comprises selecting a pair of photos from a database sample set as well as portraits inside portrait pairs as a target portrait; blocking the target portrait and dividing the blocked target portrait to obtain a first portrait block subset and a second portrait block subset; performing matrix decomposition on the obtained first portrait block subset to obtain a projection matrix, and projecting the second portrait block subset onto the projection matrix to obtain a first projection coefficient set; projecting portrait blocks, which are obtained by blocking a testing photo, onto the projection matrix to obtain a second projection coefficient set; searching for matched image blocks from the first projection coefficient set according to the similarity scale distance of the second projection coefficient set, composing the searched image blocks to obtain an initial composite image; performing iterative composition to obtain a final composite image. The single target portrait-based face portrait compositing method saves a process of taking time and labor to collect a large number of photos and portrait pairs and facilitates composition of portraits in various styles.