Methods, systems, and apparatus, including computer programs encoded on computer storage media, for restructuring an image processing pipeline. The method includes compiling program code targeted for an image processor having programmable stencil processors composed of respective two-dimensional execution lane and shift register circuit structures. The program code is to implement a directed acyclic graph and is composed of multiple kernels that are to execute on respective ones of the stencil processors, wherein the compiling includes performing any of: horizontal fusion of kernels; vertical fusion of kernels; fission of one of the kernels into multiple kernels; spatial partitioning of a kernel into multiple spatially partitioned kernels; or splitting the directed acyclic graph into smaller graphs.