Description:SAME AS UPLOADED , Claims:1. A video decoder configured to
decode a video from a video data stream by decoding a decoded picture from one or more video coding units (100) within an access unit, AU, of the video data stream in a manner parametrized using one or more predetermined coding parameters;
derive the predetermined coding parameters (122) from a plurality of parameter sets (120) which are interspersed into video data stream,
read identifiers (200) from a predetermined unit (124) of the access unit, AU, which identify predetermined parameter sets out of the plurality of parameter sets, which comprise the predetermined coding parameters.

2. The video decoder of claim 1, wherein
the predetermined unit of the AU comprises a flag (204) indicative of whether the identifiers (200) are present in the predetermined unit or not.

3. The video decoder of claims 1 or 2, wherein
the plurality of parameter sets (120) are of different hierarchy levels, wherein the one or more video coding units comprise identifiers which refer to first predetermined parameter sets (126) within one or more first predetermined hierarchy levels, wherein the first predetermined parameter sets (126) within the one or more first predetermined hierarchy levels comprise identifiers which refer to second predetermined parameter sets (128) within one or more second predetermined hierarchy levels, the first and second predetermined parameter sets being contained by the predetermined parameter sets (122).

4. The video decoder of claim 3, wherein the identifiers read from the predetermined unit (124) of the access unit, AU, identify all predetermined parameter sets directly or indirectly referred to by the one or more video coding units of the access unit so that, if all predetermined parameter sets identified by the identifiers are available, the access unit is decodable.

5. The video decoder of any one of claims 1 to 4, wherein
the predetermined unit of the AU comprises a flag (204) indicative (205) of whether either
predetermined identifiers of the identifiers (200) which refer to specific predetermined parameter sets (126b) are present in the predetermined unit (124), or
the predetermined identifiers which refer to the specific predetermined parameter sets (126b) are present in the one or more video coding units (100).

6. The video decoder of any one of claims 1 to 5, wherein
the first predetermined parameter sets (126) comprise
third predetermined parameter sets (126a) which are referred to by identifiers in the one or more video coding units (100), and
fourth predetermined parameter sets (126b) which are referred to by identifiers (200) present in the predetermined unit (124), but are neither referred to by any of the identifiers in the one or more video coding units (100), nor by any of the predetermined parameter sets.

7. The video decoder of claim 1, wherein
the predetermined unit of the AU comprises one or more of
one or more identifiers of one or more adaptive parameter sets, APSs,
one or more identifiers of one or more picture parameter sets, PPSs,
an identifier for a video parameter set, VPS,
an identifier for a decoder parameter set, DPS, and
one or more identifiers of one or more sequence parameter sets, SPS.

8. The video decoder of claim 1 or 7, wherein
the plurality of parameter sets comprises
a video parameter set, VPS,
a decoder parameter set, DPS,
a sequence parameter set, SPS,
one or more picture parameter sets, PPSs, and
one or more adaptive parameter sets, APSs.

9. The video decoder of any one of claims 15 to 22, wherein
the predetermined unit of the AU is an access unit delimiter, AUD.

10. A method comprising:
decoding a video from a video data stream by decoding a decoded picture from one or more video coding units (100) within an access unit, AU, of the video data stream in a manner parametrized using one or more predetermined coding parameters;
deriving the predetermined coding parameters from a plurality of parameter sets which are interspersed into video data stream,
reading identifiers (200) from a predetermined unit of the access unit, AU, which identify predetermined parameter sets out of the plurality of parameter sets, which comprise the predetermined coding parameters.