We propose the use of MetaOCaml for rapid prototyping of domain-specific languages. Interpretation is an easy way to implement such languages. MetaOCaml can eliminate the overhead of interpretation by a partial evaluation of the interpreter with respect to the application program. Additional aggressive optimizations are possible in the absence of general recursion. The example domain is image processing, in which the domain-specific language permits the specification of convolution matrices, summations, case distinctions and non-local pixel accesses. As an important feature, the user need not consider binding times. All expressions known at compile time are simplified and all remaining expressions are turned into MetaOCaml code parts which are combined to form the compiled application program. The example specifications deal with gradient filtering and zooming with two kinds of interpolation. The experimental results show significant speedups if partial evaluation is used for elimination of interpretation overhead and simplification of expressions.