CPC H04N 19/13 (2014.11) [H03M 7/42 (2013.01); H04N 19/124 (2014.11); H04N 19/132 (2014.11); H04N 19/174 (2014.11); H04N 19/184 (2014.11); H04N 19/50 (2014.11); H04N 19/513 (2014.11); H04N 19/52 (2014.11); H04N 19/61 (2014.11); H04N 19/70 (2014.11); H04N 19/91 (2014.11)] | 4 Claims |
1. A decoder for decoding a video encoded in a data stream into which syntax elements are encoded using binarizations of the syntax elements, the decoder comprising:
an entropy decoder configured to derive a number of bins of the binarizations from the data stream using binary entropy decoding by selecting a context among different contexts, and
updating probability states associated with the different contexts, dependent on previously decoded portions of the data stream;
a desymbolizer configured to debinarize the binarizations of the syntax elements to obtain integer values of the syntax elements; and
a reconstructor configured to reconstruct the video based on the integer values of the syntax elements using a quantization parameter,
wherein the entropy decoder is configured to initialize the probability states associated with the different contexts at beginnings of slices of the video by reading the quantization parameter for a current slice from the data stream and initializing the probability states associated with the different contexts according to a linear equation of the quantization parameter for the current slice,
wherein the entropy decoder is configured to, for each of the different contexts for each of the slices, derive a slope and an offset of the linear equation from first and second halves of a respective initialization value,
wherein the slope and the offset for the linear equations of the quantization parameter do not vary between slices.
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