1. A method of generating a delta file, the delta file including update instructions for causing a target processing device to transform a current memory image module into an updated memory image module; the method comprising: incorporating a parametric representation of a first memory address in the delta file, the parametric representation being parametric with respect to at least the location of the current memory image module in memory space and the location of the updated memory image module in memory space; and incorporating parameter resolution instructions in the delta file, wherein the method includes a pre-processing step, a delta file generation step, and a post-processing step, wherein the pre-processing step includes: generating respective canonical representations of respective relocatable versions of the current and updated memory image modules, wherein symbolic references to memory addresses are replaced by predetermined memory content; and forwarding information about the replaced symbolic references to the post-processing step; wherein the delta file generation step includes generating a delta file from the canonical representations of the relocatable current and updated memory image modules; and wherein the post-processing step includes generating the parameter resolution instructions from the forwarded information about replaced symbolic references and from the generated delta file.