Extension data handling

1. A decoding apparatus, comprising:

a processor; and

a memory storing instructions which when executed cause the decoding apparatus to:

receive an encoded representation of a slice of a picture, the encoded representation of the slice comprising a slice header and slice data immediately following the slice header;

identify, based on a picture parameter set identifier in the slice header, a picture parameter set associated with the encoded representation of the slice;

determine, based on a slice header extension present flag included in the picture parameter set, whether or not the slice header comprises an extension field;

when the slice header extension present flag indicates that the slice header comprises the extension field:

parse a length value from the slice header, the length value specifying a length of the extension field in bytes;

parse the extension field from the slice header such that each value of each byte included in the extension field is ignored; and

parse and decode the slice data subsequent to the parsing of the extension field.

2. The decoding apparatus of claim 1 , wherein the extension field immediately follows the length value in the slice header, and

wherein parsing the extension field comprises ignoring X bytes of data that immediately follow the length value, where X is the length of the extension field.

3. The decoding apparatus of claim 1 , wherein the memory further stores instructions which when executed cause the decoding apparatus to:

identify an end of the extension field in the slice header based on the length value; and

identify a start of the slice data to be a byte after the end of the extension field.

4. The decoding apparatus of claim 3 , wherein parsing and decoding the slice data begins at the start of the slice data.

5. The decoding apparatus of claim 3 , wherein the byte after the end of the extension field is after byte alignment data.

6. The decoding apparatus of claim 1 , further comprising a receiver, wherein the receiving of the encoded representation of the slice is performed by the receiver.

7. A decoding method, comprising:

receiving, by a decoder, an encoded representation of a slice of a picture, the encoded representation of the slice comprising a slice header and slice data immediately following the slice header;

identifying, based on a picture parameter set identifier in the slice header, a picture parameter set associated with the encoded representation of the slice;

determining, based on a slice header extension present flag included in the picture parameter set, whether or not the slice header comprises an extension field;

when the slice header extension present flag indicates that the slice header comprises the extension field:

parsing a length value from the slice header, the length value specifying a length of the extension field in bytes;

parsing the extension field from the slice header such that each value of each byte included in the extension field is ignored; and

parsing and decoding the slice data subsequent to the parsing of the extension field.

8. The method of claim 7 , wherein the extension field immediately follows the length value in the slice header, and

wherein parsing the extension field comprises ignoring X bytes of data that immediately follow the length value, where X is the length of the extension field.

9. The method of claim 8 , comprising:

identifying an end of the extension field in the slice header based on the length value; and

identifying a start of the slice data to be a byte after the end of the extension field.

10. The method of claim 9 , wherein parsing and decoding the slice data begins at the start of the slice data.

11. The method of claim 9 , wherein the byte after the end of the extension field is after byte alignment data.

12. A non-transitory computer readable medium storing instructions for decoding a slice of a picture, wherein the instructions, when executed by a processor, cause the processor to:

identify, based on a picture parameter set identifier in the slice header, a picture parameter set associated with the encoded representation of the slice;

determine, based on a slice header extension present flag included in the picture parameter set, whether or not the slice header comprises an extension field;

when the slice header extension present flag indicates that the slice header comprises the extension field:

parse a length value the slice header, the length value specifying a length of the extension field in bytes; and

parse the extension field from the slice header such that each value of each byte included in the extension field is ignored; and

parse and decode the slice data subsequent to the parsing of the extension field.

13. The non-transitory computer readable medium of claim 12 , wherein the extension field immediately follows the length value in the slice header, and

wherein parsing the extension field comprises ignoring X bytes of data that immediately follow the length value, where X is the length of the extension field.

14. The non-transitory computer readable medium of claim 12 , wherein the memory further stores instructions which when executed cause the processor to:

identify an end of the extension field in the slice header based on the length value; and

identify a start of the slice data to be a byte after the end of the extension field.

15. The non-transitory computer readable medium of claim 14 , wherein parsing and decoding the slice data begins at the start of the slice data.

16. The non-transitory computer readable medium of claim 14 , wherein the byte after the end of the extension field is after byte alignment data.