Significant coefficient flag encoding for point cloud attribute compression

A device, comprising:

• a memory storing program instructions for compressing attribute values associate with points of a set of points in three-dimensional space;
• and
• one or more processors, wherein the program instructions, when executed by the one or more processors, cause the one or more processors to:
• determine, for each point of the set of points, whether respective values of one or more attribute coefficients associated with the respective point comprise one or more significant values or do not comprise a significant value;
• assign to points that have attribute coefficients that comprise one or more significant values a first binary flag value and assign to points that have attribute coefficients values that do not comprise a significant value a second binary flag value;
• evaluate the binary flag values assigned to the points of the set of points to identify consecutive points assigned the first binary flag value and consecutive points assigned the second binary value;
• for respective runs of points having the first binary flag value as a same assigned binary flag value and for respective runs of points having the second binary flag value as a same assigned binary flag value:
• encode a value indicating a length of the respective run using a variable-length encoding technique.

A non-transitory computer-readable medium storing program instructions, that when executed on or across one or more processors, cause the one or more processors to:

• receive a sequence of encoded values, encoded using a variable length encoding technique, wherein the encoded values indicate lengths of respective runs of binary flag with a same value, wherein each binary flag value represents whether or not attribute coefficient values for attributes of a point comprise significant or non-significant values, wherein each point, of a set of points whose attribute values have been compressed, is assigned at least one binary flag value;
• decode the encoded values using a variable length decoding technique to determine respective run lengths of the respective runs;
• for respective runs having a first binary flag value as a same assigned binary flag value, mark the points associated with the respective runs for further processing to determine attribute coefficient values for the points of the respective runs;
• and
• for other respective runs having a second binary flag value as a same assigned binary flag value, assign a zero value to the attribute coefficients for the points associated with the other respective runs.