Method for producing video coding and computer program product
According to the invention, there are provided sets of contexts specifically adapted to encode special coefficients of a prediction error matrix, on the basis of previously encoded values of level k. Furthermore, the number of values of levels other than 0 is explicitly encoded and numbers of appropriate contexts are selected on the basis of the number of spectral coefficients other than 0.
1. A device for video coding for a current image represented by macroblocks and part of a bit stream, the device comprising:
a processor; and
a machine-readable memory, the memory storing instructions that, when loaded and executed by the processor, cause the processor to:
provide a prediction error matrix;
convert the prediction error matrix by coefficient sampling into a series of symbols; and
perform context-adaptive arithmetic encoding of the symbols on the basis of symbol frequencies with an already-encoded symbol, the already-encoded symbol appearing immediately before a given symbol for which context-adaptive arithmetic encoding is performed.
2. A device as recited in claim 1 , in which the prediction error matrix is converted by coefficient sampling into a series of levels and lengths of zero sequences.
3. A device as recited in claim 2 , in which the levels and lengths are represented as unary values.
4. A device as recited in claim 1 , in which the levels are arithmetically encoded context-adaptively in each case, with the distribution of the underlying level value frequencies being selected depending on a level value encoded beforehand in each case.
5. A device as recited in claim 2 , in which the lengths are arithmetically encoded context-adaptively in each case, with the distribution of the underlying length value frequencies being selected depending on the length value encoded beforehand in each case.
6. A device as recited in claim 2 , in which the level values are sorted before the context-adaptive arithmetic encoding in accordance with 2 level values.
7. A device as recited in claim 2 , in which the number of symbols read out for coefficient sampling is encoded and transmitted.
8. A device as recited in claim 7 , in which the selection of the distribution of symbol frequencies is undertaken depending on the number of symbols read out.