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This commit moves the non-normative inverse position scaling process
from the codec's reconstruction process into the ply writer.  This
is to support changing the internal point cloud position representation
to integer.

Reducing the search range from 8 to 1 significantly reduces the time
spent recolouring.  The value of 1 seems to be a reasonable trade-off
between distortion and runtime.

Sebastien Lasserre authored Jun 10, 2019 and David Flynn committed Nov 21, 2019

This commit introduces planar modes, in the three x,y, and directions,
as new representations of the geometry. Planar modes are activated at
eligible nodes through a planar mode activation flag coded in the
bitstream.  Extra syntax is added to the bitstream to indicate the
position of the plane associated with activated planar modes.

A local eligibility criteria avoids using planar modes in adverse
regions of the point cloud and thus avoiding worse compression
performance, particularly on dense point clouds.

Xiang Zhang authored Jun 10, 2019 and David Flynn committed Nov 21, 2019

This adoption permits coding geometry with non-cubic bounding boxes.
Since the depth of the tree remains constant for cubic and non-cubic
bounding boxes with identical largest dimensions, quad-tree and
binary-tree partitions are introduced to avoid coding 'fractional'
positions.

The following configuration options control the placement of non-octree
partitions within the coding tree:

 --max_num_implicit_qtbt_before_ot
 --min_implicit_qtbt_size_log2

Xiang Zhang authored Aug 19, 2019 and David Flynn committed Nov 21, 2019

This extends the geometry based quantisation scheme to:
 - add a per-slice QP offset, and
 - permit uniform quantisation of the whole slice without
   requiring signalling of an additional node QP offset.

Per node QP offset signalling is disabled by setting
positionQuantisationOctreeDepth=-1

Xiang Zhang authored Aug 19, 2019 and David Flynn committed Nov 21, 2019

This introduces a quantization scheme into the octree coding process,
enables adaptive geometry quantization for different regions of the
point cloud.  This in-loop scheme is independent of the any quantisation
performed in non-normative pre-processing at the input to the encoder.

At a particular depth of the octree, the remaining (uncoded) position
bits of each point are quantised according to a per-node (or rather,
per-subtree) QP.  The QP itself is signalled as an offset to a base QP.

The following configuration parameters are added:
  positionQuantisationEnabled
  positionBaseQp
  positionQuantisationOctreeDepth

Sehoon Yea authored Sep 25, 2019 and David Flynn committed Nov 21, 2019

This commit adds the lossless YCgCoR colour transform.
The CTC configuration is updated to use YCgCoR for lossless
attribute coding instead of inter-component prediction on
GBR (colourMatrix=0) data.

Some imput formats and colour spaces have a different bitdepth
for their chroma (non-primary) component.  This commit adds
support to signal their bitdepth as described by the codec
independent code points.

This commit enables signalling a colour matrix index using
cicp_matrix_coefficients_idx (ISO/IEC 23001-8 codec independent code
points).

It adds the following options that replace the existing colorTransform
option:

 - colourMatrix: The coded representation according to ISO/IEC 23001-8.

 - convertPlyColourspace: Enables conversion to/from RGB using the
   indicated matrix.

Configuration files are updated to use the new option and to
signal the identity matrix in the case of direct GBR coding.

Sehoon Yea authored Sep 25, 2019 and David Flynn committed Nov 21, 2019

In order to support bit depths higher than 8bit, this commit adds
an attr_t type to represent attribute data.  Existing uses of
uint8_t and uint16_t are converted to attr_t.

Sehoon Yea authored Sep 25, 2019 and David Flynn committed Nov 21, 2019

This adoption permits prediction of residuals between components of
the same attribute, coding the residual resulting from this second
prediction.

Yiting Shao authored Sep 23, 2019 and David Flynn committed Nov 21, 2019

This adoption allows determining the weights of each point's
predicting neighbours with a reduced influence of the, for
instance, z component.

This adoption permits encoding the geometry positions in an order other
than {x,y,z}.  The --geometry_axis_order option causes the encoder to
load data from the ply file in a different order.  The order is
signalled in the SPS and the decoder will label the output axis as
appropriate.

This commit migrates PCCPointSet3::read and write to ply::read and write.

David Flynn authored Jun 21, 2018 and David Flynn committed Nov 21, 2019

This commit enables the codec to encapsulate more than one frame in the
coded bitstream.  The number of frames to encode is controlled by the
frameCount option.

Support is added to encode multiple source frames from separate ply
files based on a template input file name.  A printf-like "%d" directive
acts as a placeholder for the current frame number.

Decoding functions in a similar way with a each frame decoded from the
bitstream being written to a separate ply file named according to a
template pattern.

The first frame number used for file I/O may be set using the
firstFrameNum option.

Satoru KUMA authored May 31, 2019 and David Flynn committed Nov 21, 2019

This provides a means to achieve spatial scalability for a G-PCC
bitstream.  For bitstreams encoded with aps_scalable_enabled_flag set,
the decoder may partially decode the geometry octree
(minGeomNodeSizeLog2) and the corresponding point attributes.  The
functionality is achieved by constraining the LoD generation process to
align with partial geometry decoding.

Yiting Shao authored Jun 14, 2019 and David Flynn committed Aug 12, 2019

Adjust the operation sequence of slice partition and geometry quantization. We
do geometry quantization first and then do the slice partition, so that the
point number of each slice would be kept in the predefined range under
lossless/lossy geometry coding conditions.

David Flynn authored Feb 13, 2019 and David Flynn committed Aug 12, 2019

Rather than code bypass bins using a simplified mode of the
arithmetic coder, this commit adds the ability to signal bypass bins
in a separate byte-reversed sub-stream.

Noritaka Iguchi authored Jul 02, 2019 and David Flynn committed Aug 12, 2019

This commit allow individual QP offsets to be specified for each
LoD/RAHT layer in attribute coding.

This placeholder is for any encoder-specific per-attribute parameters
that do not belong in the SPS, APS, etc.,

Arash Vosoughi authored Jul 22, 2019 and David Flynn committed Aug 12, 2019

This commit implements the recolouring method described in m47800, which
notably uses a distance-weighted average rather than the previous
unweighted average.

For each 2×2×2 block, a predicted block is produced by upconverting the
previous transform level.  The prediction is transformed and subtracted
from the transformed attributes at the encoder.

David Flynn authored Feb 22, 2019 and David Flynn committed Aug 12, 2019

In order to support transform domain prediction of AC coefficients using
upsampled previously reconstructed transform levels, this commit
replaces the existing RAHT implementation with a descent based RAHT tree
traversal for both encoder and decoder with the transform performed in
units of 2×2×2 blocks.

Toshiyasu Sugio authored Mar 01, 2019 and David Flynn committed Apr 16, 2019

This commit introduces prediction by previously coded points within
the same level of detail using the predicting attribute coder.
The feature is controlled using --intraLodPredictionEnabled=0|1.

This method has been replaced by an LoD decimation method.

Valery Valentin authored Mar 05, 2019 and David Flynn committed Apr 16, 2019

This LoD generation (subsampling) method uses the Morton-based ordering
of points that is used to determine prediction neighbours.  Each LoD
level comprises 3/4 of the points of the previous.

This commit permits signalling a per-slice delta QP for luma and
chroma attribute components.  The delta is relative to the base
value derived from the APS.

NB: while syntax support and derivation processes are provided,
this commit does not contain any method to control the delta
QP value at the encoder.

Noritaka Iguchi authored Mar 27, 2019 and David Flynn committed Apr 16, 2019

This commit introduces control of the quantisation step size using
the familiar HEVC | AVC quantisation parameter.

This is part of a series attempting to remove unhelpful typedefs.

The commit adds a flag to conditionally enable/disable the feature.

Yiting Shao authored Dec 07, 2018 and David Flynn committed Feb 06, 2019

This partitioning method (--partitionMethod=3) decomposes the input
pointcloud into an octree of depth --partitionOctreeDepth=d, with
each leaf node corresponding to a slice.

Yiting Shao authored Dec 07, 2018 and David Flynn committed Feb 06, 2019

This partitioning method (--partitionMethod=2) finds the longest edge of
the point cloud and divides it into --partitionNumUniformGeom=n slices
along the longest edge.

If n = 0, the ratio of longest edge to shortest edge determines
the number of slices.

This commit provides a basic frame work for partitioning a frame into
multiple slices, with the continued assumption of single-frame
sequences.

The decoder is modified to independently decode each slice and
accumulate decoded points in a buffer for output.

The encoder is updated to support partitioning the input point cloud
into slices and to independently code each slice.  Points from
reconstructed slices are accumulated and output at the end of the
frame period.

The partitioning process (partitioning methods are defined in
partitioning.cpp) proceeds as follows:

 - quantise the input point cloud without duplicate point removal
   or reordering points.

 - apply the partitioning function to produce a list of tiles
   and slices, each slice having an origin, id, and list of point
   indexes that identify points in the input point cloud.

 - producing a source point cloud for each partition as a subset
   of the input point cloud.

 - compressing each partition (slice) as normal by quantising
   the partitioned input.  Recolouring is necessarily performed
   against the partitioned input since the recolouring method
   cannot correctly handle recolouring a partition from a complete
   point cloud.

NB: this commit does not provide any partitioning methods.

Vladyslav Zakharchenko authored Dec 14, 2018 and David Flynn committed Feb 06, 2019

This uses a binary-tree to generate the levels-of-details for the
lifting/predicting transforms as an alternative to Euclidean distance
thresholding methods.

Jungsun Kim authored Jan 30, 2019 and David Flynn committed Feb 05, 2019

This simplified attribute prediction scheme avoids computing the
LoD structure in order to reduce the computational complexity of
both the encoder and the decoder.  It is activated by setting
levelOfDetailCount=0.

NB: this is only configured for lossless/near-lossless predictive
attribute coding of cat3 sequences.

The configuration parameters seq_bounding_box_xyz0 and
seq_bounding_box_whd allow overriding the automatic derivation of
frame (sequence) bounding box, forcing the depth of the geometry
tree.

NB: seq_bounding_box_xyz0 and seq_bounding_box_whd are specified
    using unscaled co-ordinates.

NB: this patch does not signal these parameters in the SPS.

Define po-lite option traits to handle PCCVector3<T> as a container
to permit using PCCVector3<T> types as command / config parameters.