1. An apparatus comprising: a memory; and a processor coupled to the memory, the processor configured to: receive a block of input sample values via an interface, and perform a full two-dimensional (2D) inverse transform on the block of input values to obtain a block of output values, comprising: performing a scaled one-dimensional (1D) transform on each row of the block of input sample values to obtain a first intermediate block, performing a scaled 1D transform on each column of the first intermediate block to obtain a second intermediate block comprising scaled transform coefficients, and scaling the second intermediate block to obtain a block of output values.