Digital Image Processing by Gonzalez, Woods is the standard image processing textbook.  It comes in two forms, the theoretical version and a Matlab coding version.  The Matlab version contains example Matlab code and ideas of how to implement the theory in the main book.

The Warping and Morphing of Graphical Objects is a standard textbook on the theory of morphing and contains significant background in this area.

Rossion, Is sex categorization from faces really parallel to face recognition?, Visual Cognition, 2002, 9 (8), 1003–1020 - PDF - Author

Rotshtein, Treves, Henson, Driver, Dolan, Morphing Marilyn into Maggie dissociates physical and identity face representations in the brain, Nature Neuroscience 8, 107-113(01 Jan 2005) - PDF

Singh, Papanikolopoulos, Planar shape recognition by shape morphing, Pattern Recognition 33(2000) 1683-1699