Scaling list signalling for video coding

A device for decoding video data, the device comprising:

• a memory configured to store video data;
• one or more processors implemented in circuitry and configured to:
• determine a set of scaling lists for the video data, wherein each scaling list of the set of scaling lists is used to determine an associated scaling matrix in a set of scaling matrices, and wherein each scaling list and each associated scaling matrix determined has an associated identification (ID) number;
• determine that a new scaling list for the set of scaling lists is to be predicted from a reference scaling list, wherein the new scaling list corresponds to a new scaling matrix;
• receive a syntax element;
• determine an ID number based on the syntax element;
• determine that the set of scaling lists does not include a scaling list with the ID number,. wherein to determine that the set of scaling lists does not include the scaling list with the ID number, the one or more processors are further configured to determine that the ID number divided by 3 has a remainder of 0 or 1;
• in response to determining that the set of scaling lists does not include a scaling list with the ID number, determine the new scaling matrix based on a set of default values;
• decode the video data based on the new scaling matrix;
• and
• output the decoded video data.

A computer-readable storage medium storing instructions that when executed by one or more processors cause the one or more processors to:

• determine a set of scaling lists for the video data, wherein each scaling list of the set of scaling lists is used to determine an associated scaling matrix in a set of scaling matrices, and wherein each scaling list and each associated scaling matrix determined has an associated identification (ID) number;
• determine that a new scaling list for the set of scaling lists is to be predicted from a reference scaling list, wherein the new scaling list corresponds to a new scaling matrix;
• receive a syntax element;
• determine an ID number based on the syntax element;
• determine that the set of scaling lists does not include a scaling list with the ID number,. wherein to determine that the set of scaling lists does not include the scaling list with the ID number, the instructions cause the one or more processors to determine that the ID number divided by 3 has a remainder of 0 or 1;
• in response to determining that the set of scaling lists does not include a scaling list with the ID number, determine the new scaling matrix based on a set of default values;
• decode the video data based on the new scaling matrix;
• and
• output the decoded video data.

A device for decoding video data, the device comprising:

• a memory configured to store video data;
• one or more processors implemented in circuitry and configured to:
• determine a set of scaling lists for the video data, wherein each scaling list of the set of scaling lists is used to determine an associated scaling matrix in a set of scaling matrices, and wherein each scaling list and each associated scaling matrix determined has an associated identification (ID) number;
• determine that a new scaling list for the set of scaling lists is to be predicted from a reference scaling list, wherein the new scaling list corresponds to a new scaling matrix;
• receive a syntax element;
• determine an ID number based on the syntax element;
• determine that the set of scaling lists does not include a scaling list with the ID number, wherein to determine that the set of scaling lists does not include the scaling list with the ID number, the one or more processors are further configured to determine that the video data is coded without chroma components and determine that the ID number corresponds to a scaling list for a chroma component;
• in response to determining that the set of scaling lists does not include a scaling list with the ID number, determine the new scaling matrix based on a set of default values;
• decode the video data based on the new scaling matrix;
• and
• output the decoded video data.