1. A method for shape and material recovery from object motion, comprising: modeling the correct dichromatic dependence of surface reflectance on surface normal, lighting and viewing directions to derive a differential flow relation; determining a rank deficiency in a sequence of differential flow relations and use the rank deficiency to handle complex bidirectional reflectance distribution functions (BRDFs); estimating BRDF-derivatives from the differential flow relations to recover the complex BRDF; and reconstructing depth of objects without knowledge of their BRDFs for joint shape and material recovery.