1. An image processing apparatus, comprising: one or more processors to: receive a plurality of source data blocks, wherein individual source data blocks are each associated with a fragment of a source image to be processed into a destination image; receive an image graph specifying a pipeline comprising a plurality of image processing operations to be performed on each of the source data blocks to generate corresponding fragments of the destination image; determine, from one or more mapping functions associated with each node in the graph, data block dependency information indicative of a first data block upon which a second data block output by the corresponding node depends, wherein each of the first and second data blocks is associated with an image fragment; schedule execution of the image processing operations based, at least in part, on the data block dependency information; and execute the image processing operations as scheduled; and an electronic memory to store the first data blocks and second data blocks as they are consumed and produced by the processors.