Provided are methods and apparatuses for encoding and decoding
three-dimensional object data, which consists of point texture data,
voxel data, or octree data. The method of encoding three-dimensional
object data involves generating three-dimensional object data having a
tree structure in which nodes are attached labels indicating their types;
encoding nodes of the three-dimensional object data; and generating the
three-dimensional object data whose nodes are encoded into a bitstream.
The apparatus for encoding three-dimensional object data includes a tree
structure generator which generates three-dimensional object data having
a tree structure in which nodes are attached labels indicating their
types; a merging order selector which merges the nodes of the
three-dimensional object data by referring to their labels; a node
encoder which encodes merged nodes; and a bitstream generator which
generates the three-dimensional object data whose merged nodes are
encoded into a bitstream. The method of decoding three-dimensional object
data involves reading-continue flag information from a bitstream of
encoded three-dimensional object data and decoding the continue flag
information; decoding note type information of the bitstream; decoding an
`S` node if the note type information indicates that a current node is an
`S` node and decoding a PPM node if the note type information indicates
that the current node is a PPM node; and restoring the three-dimensional
object data whose nodes are encoded to a tree structure. The apparatus
for decoding three-dimensional object data includes a bitstream reader
which receives a bitstream of encoded three-dimensional object data; a
node decoder which decodes the bitstream; and a tree structure restorer
which restores decoded nodes to a tree structure.