I believe such product would comes with software, installation guide and support. Unless there are special requirements from the user that require software developer to customise certain functions.
I assumed that they daisy-chained the video through all the n x m LED matrix modules, and each module would pick out and display just its relevant block from the complete video signal, but according to this:
"Typically, a number of external control units are also required, each unit responsible for a subset of the tiles in the wall. Each control unit accepts video signals from source devices and provides a separate video output for each subgroup of tiles. Most solutions include a video processor and universal routing switches, as well as content management and collaboration systems."