Method of an image processor for transforming a n-bit data packet to a m-bit data packet using a lookup table

A method of transforming a n-bit data packet to a m-bit data packet with a lookup table. The lookup table includes at least one entry data packet and at least one respective delta value associated with each entry data packet. The method includes the acts of receiving an input data packet having n-bits, indexing the lookup table with at least a portion of the input data packet to obtain one of the at least one entry data packet, and decompressing the obtained entry data packet with the at least one respective delta value associated with the obtained entry data packet, thereby resulting in an output data packet having m-bits. The decompressing act includes using a portion of the input data packet to determine the number of delta values called for decompressing the obtained entry data packet. The method can be used in, for example, an image processor.