In the contextualisation of occupancy coding using neighbour patterns,
this commit replaces the case when neighbour contextualisation is
disabled with a constraint that restricts neighbour contextualisation
only examine the direct siblings of a node.

The restriction ensures that at most three neighbours may be present
for a node.

The configuration option "neighbourContextualisation=1" is replaced with
"neighbourContextRestriction=0".

This commit provides an implementation of m42522 to code occupancy
using a binary context model rather than a 255-ary model.  A total of
581 binary contexts are used compared to the previous 10 255-ary
contexts.

This commit removes the bundled Intel Threading Building Blocks library
from the repository.

This commit adds support for setting encflags, decflags and pcerrorflags
at the top-level of the config which are then applied to all categories.
Precedence is such that global enc/dec/pcerror flags are set after all
other more-specific definitions.

The gen-cfg.pl tool permits the merging of yaml input prior to
generation of the derived configuration files.

This commit permits merging of existing arrays.  For example,
given the following input (in order):

 file a: "{ key: [a] }"
 file b: "{ key: [b] }"

The merged structure is { key: [a, b] }.

The provision of these configuration files causes confusion when they
are not kept in sync with the .yaml files -- either due to modification
of the .yaml files without regenerating the .cfg files, or due to
direct modification of the .cfg files themselves.

Please see cfg/README.md for further details on how to generate
configuration files for the encoder/decoder.

The original integration of IDCM implemented only the parent based
eligibility check of m42239 and erroneously omitted the six-neighbour
check.

This commit adds the six-neighbour check, making use of the neighbour
calculation from m42239 neighbour contextualised coding of occupancy.

This commit fixes a null pointer dereference in cases where no
reconstructed point cloud output is specified.

This commit makes gen-cfg understand a pcerrorflag value on a
per test category basis in the same way as enc|decflags.

This commit updates the master configuration files to support:

 - new test conditions for cat3 tests
 - existing conditions for cat1 tests (for use by tmc13)
 - updates enc/decflags to use recommended forms
 - integrates pcerror flags (per condition / sequence)
 - adds sequence databases describing source files, and source
   parameters that may be used by other scripts.

The ctc-category-map.csv file has been removed -- a new version can be
provided if necessary.

If there is an issue running one of the tmc1 blocks, terminate
the encoding immediately and report the error.

This commit aims to reduce te amount of copy+paste code used to
support the three different geometry coding modes by unifying them
into a single flow.

This commit adds a DecoderParameters struct to reduce the overhead of
adding extra parameters.

This commit introduces signalling for geometryCodecType in the bitstream
headers in order to allow the decoder to be more easily slaved to the
bitstream -- ie, to avoid needing to configure a special decoding mode.

This commit aims to reduce the overload on the --mode option and to
restore it to the previous encode/decode functionality.  To this end,
a new option (--geometryCodec=...) is added that selects the geometry
codec.

Version v1.0 use of --mode=... is supported.

This commit adds a helper to add / remove colour and reflectance
attributes in a single shot.

This commit introduces PCCTMC3Encoder3Parameters::getAttrParams(...),
a helper to reduce the clutter in searching for attributes to code.

Little is gained from the return type checks, it mostly serves to
clutter the code.

Philip A. Chou authored Mar 29, 2018 and David Flynn committed Jun 05, 2018

This commit does not add the triangle soup geometry compressor to TMC3,
rather.  Rather, it adds a means to call out to TMC1 binaries to perform
the compression, integrate the results into the bitstream.

Attribute compression is performed natively by the TMC13 codec.

Rather than coding all syntax elements for both transform types
irrespective of the in-use type, this commit codes only those that
are necessary for a given transform type.

Philip A. Chou authored Apr 03, 2018 and David Flynn committed Jun 05, 2018

This commit introduces the rahtLeafDecimationDepth parameter to allow
chroma sub-sampling by decimating the coefficients in the bottom n
levels of the tree.

The default value of 3 provides chroma sub-sampling by a factor of 2
in each dimension.

Philip A. Chou authored Mar 25, 2018 and David Flynn committed Jun 05, 2018

This commit ports the Region Adaptive Hierarchical Transform for
attribute coding with colour and reflectance variants.

Khaled Mammou authored Mar 25, 2018 and David Flynn committed Jun 05, 2018

This commit reorganises the attribute coders to allow integration
of the RAHT variant.

In order to support multiple different attribute compression schemes,
this commit moves the existing attribute compression code into a
self-contained class.

In order to support multiple different attribute compression schemes,
this commit moves the existing attribute compression code into a
self-contained class.