Patent ID: 8520965

Claim:
A method of coding using a coding apparatus, the method comprising: for a first region in an ordered series of quantized transform coefficients of a block of image data, the quantized coefficients having 0 as a most likely-to-occur amplitude and 1 as a next-to-most likely-to-occur amplitude, the ordering from low to high spatial frequency, the first region possibly being the whole series: position encoding events that each includes a cluster of at least one non-zero quantized coefficient, the position coding of a particular cluster using a respective position code mappings selected from a plurality of predetermined position code mappings according to one or more position VLC selection criteria; and encoding in reverse order to the ordering of the series non-zero amplitudes that are still to be encoded, the encoding according to one of a plurality of pre-selected amplitude VLC mappings selected from a plurality of amplitude VLC mappings, wherein at the selecting between the position VLC mappings, between the amplitude VLC mappings, or both between the position VLC mappings and between the amplitude VLC mappings includes using a respective context-based selection criterion.