Method of encoding and decoding, encoder, and decoder

A method for decoding a bitstream of compressed point cloud data to generate a reconstructed point cloud, wherein the point cloud's geometry is represented by an octree-based structure with a plurality of nodes having parent-child relationships by recursively splitting a volumetric space containing the point cloud into sub-volumes each associated with a node of the octree-bases structure, the method comprising:

• determining eligibility of planar mode for a present node to be decoded for at least two directions;
• in the case of eligibility of planar mode in at least two directions of the present node, decoding one planar flag indicating planar context information for the at least two directions;
• and
• entropy decoding the bitstream based on the determined planar context information of the present node to reconstruct occupancy of the present node.

An encoder for encoding a point cloud to generate a bitstream of compressed point cloud data, wherein the point cloud's geometry is represented by an octree-based structure with a plurality of nodes having parent-child relationships by recursively splitting a volumetric space containing the point cloud into sub-volumes each associated with a node of the octree-based structure, the encoder comprising:

• a processor and
• a memory storage device, wherein in the memory storage device instructions executable by the processor are stored that, when executed, cause the processor to:
• determine eligibility of planar mode for a present node to be encoded for at least two directions;
• in the case of eligibility of planar mode in at least two directions of the present node, determine one planar flag indicating planar context information for the at least two directions;
• and
• entropy encode occupancy of the present node based on the determined planar context information to produce encoded data for the bitstream.