| CPC H04N 19/124 (2014.11) [H04N 19/105 (2014.11); H04N 19/13 (2014.11); H04N 19/157 (2014.11); H04N 19/176 (2014.11); H04N 19/18 (2014.11); H04N 19/184 (2014.11); H04N 19/186 (2014.11); H04N 19/61 (2014.11); H04N 19/70 (2014.11)] | 25 Claims |
|
1. Decoder configured to
decode residual levels, which represent a prediction residual, from a data stream, sequentially dequantize the residual levels by
selecting a quantizer out of a set of default quantizers depending on a current transition state,
dequantizing a current residual level using the quantizer to acquire a dequantized residual value,
applying a binary function onto the current residual level to acquire a current residual level's characteristic, and
updating the current transition state depending on the current residual level's characteristic using a transition table to be used,
reconstruct a media signal using the dequantized residual values,
select, depending on a quantization mode information comprised by the data stream, one default transition table out of a set of default transition tables as the transition table to be used, each of which represents a surjective mapping from a domain of combinations of the set of transition states with the current residual level's characteristic onto the set of transition states, wherein the default transition tables differ in a cardinality of the set of transition states, wherein the cardinality is four or larger, and
perform the selection of the quantizer by mapping, using a first mapping, a predetermined number of bits of the current transition state onto the default quantizers, wherein the predetermined number and the first mapping do not change whatever default transition table is selected as the transition table to be used.
|