An apparatus includes a processor and storage storing instructions causing the processor to store, at a node device of a grid of node devices, a data block of a data blob, receive data blob metadata indicative of an organization of data items within the data blob, receive a command to generate, from the data block, at least one row of a representation portion of a plurality of representation portions from which a 2D representation of the data blob is to be generated, use the data blob metadata and a node block map indicative of which data items of the data block are required to generate the representation portion to derive one or more transforms to be performed with the data block to generate the at least one row of the representation portion, and perform the one or more transforms with the data block to generate the at least one row.