EntropySliceMode 2 does not work properly. (EntropySliceMode 2 break the bitstream into entropy slices when a bin count (CABAC) or a bit count (CAVLC) exceeds the threshold specified by the EntropySliceArgument parameter.)

One problem is that when SliceMode is also 2, slice sizes could become significantly smaller than the specified threshold. This is fixed by ensuring that a CU which does not fit into the current entropy slice and is therefore not encoded does not count towards the budget for the current slice. Another problem is that when FINE_GRANULARITY_SLICES is defined, incorrect bin counting during compression meant that the compressor could give different results on random due to different CU splits. This is fixed by correctly initializing and updating the bin counter during compression.

A fix reative revision 1085 of HM-3.2-dev that corrects entropy slice coding for EntropySliceMode 2 is attached. There are no modifications to the decoder, only encoder entropy slice decisions are changed.