trisoup/m46530: replace trisoup hls with trisoup_node_size_log2

This commit provides trisoup_node_size_log2 as a replacement for
the following HLS syntax variables:
 - geom_codec_type (redundant wrt. triangle node size derivation)
 - trisoup_depth (redundant wrt. bounding box)
 - trisoup_triangle_level (semantics simplified)

The following config options have been removed:
 - geometryCodec (redundant wrt. trisoup_node_size_log2)
 - triSoupLevel  (replaced by trisoup_node_size_log2)
 - triSoupDepth  (unnecessary)
 - triSoupIntToOrigScale (redundant wrt. positionQuantizationScale)

cfg/octree-liftt-ctc-lossless-geom-lossy-attrs.yaml

@@ -9,7 +9,7 @@ categories:
      ##
      # geometry parameters (octree)
      #  - preserve lossless geometry property
-     - geometryCodec: 1
+     - trisoup_node_size_log2: 0
      - mergeDuplicatedPoints: 0
      - ctxOccupancyReductionFactor: 3
      - neighbourAvailBoundaryLog2: 8

cfg/octree-liftt-ctc-lossy-geom-lossy-attrs.yaml

@@ -8,7 +8,7 @@ categories:
 
      ##
      # geometry parameters (octree)
-     - geometryCodec: 1
+     - trisoup_node_size_log2: 0
      - mergeDuplicatedPoints: 1
      - ctxOccupancyReductionFactor: 3
      - neighbourAvailBoundaryLog2: 8

cfg/octree-predt-ctc-lossless-geom-lossless-attrs.yaml

@@ -12,7 +12,7 @@ categories:
 
      ##
      # geometry parameters (octree)
-     - geometryCodec: 1
+     - trisoup_node_size_log2: 0
      - ctxOccupancyReductionFactor: 3
      - neighbourAvailBoundaryLog2: 8
      - intra_pred_max_node_size_log2: 6

cfg/octree-predt-ctc-lossless-geom-nearlossless-attrs.yaml

@@ -12,7 +12,7 @@ categories:
 
      ##
      # geometry parameters (octree)
-     - geometryCodec: 1
+     - trisoup_node_size_log2: 0
      - ctxOccupancyReductionFactor: 3
      - neighbourAvailBoundaryLog2: 8
      - intra_pred_max_node_size_log2: 6

cfg/octree-raht-ctc-lossless-geom-lossy-attrs.yaml

@@ -9,7 +9,7 @@ categories:
      ##
      # geometry parameters (octree)
      #  - preserve lossless geometry property
-     - geometryCodec: 1
+     - trisoup_node_size_log2: 0
      - mergeDuplicatedPoints: 0
      - ctxOccupancyReductionFactor: 3
      - neighbourAvailBoundaryLog2: 8

cfg/octree-raht-ctc-lossy-geom-lossy-attrs.yaml

@@ -8,7 +8,7 @@ categories:
 
      ##
      # geometry parameters (octree)
-     - geometryCodec: 1
+     - trisoup_node_size_log2: 0
      - mergeDuplicatedPoints: 1
      - ctxOccupancyReductionFactor: 3
      - neighbourAvailBoundaryLog2: 8

cfg/trisoup-liftt-ctc-lossy-geom-lossy-attrs.yaml

@@ -9,20 +9,18 @@ categories:
 
      ##
      # geometry parameters (trisoup)
-     - geometryCodec: 2
      - ctxOccupancyReductionFactor: 3
      - neighbourAvailBoundaryLog2: 8
      - intra_pred_max_node_size_log2: 6
      - inferredDirectCodingMode: 0
-     - triSoupDepth: ${test-depth}
-     - triSoupIntToOrigScale: '$eval{ 1 << ( ${src-geometry-precision} - ${test-depth} ) }'
-     - triSoupLevel:
-         r01: '$eval{ ${test-depth} - 4 }'
-         r02: '$eval{ ${test-depth} - 3 }'
-         r03: '$eval{ ${test-depth} - 3 }'
-         r04: '$eval{ ${test-depth} - 3 }'
-         r05: '$eval{ ${test-depth} - 2 }'
-         r06: ${test-depth}
+     - positionQuantizationScale: '$eval{ 1 / (1 << ( ${src-geometry-precision} - ${test-depth} )) }'
+     - trisoup_node_size_log2:
+         r01: 4
+         r02: 3
+         r03: 3
+         r04: 3
+         r05: 2
+         r06: 0
 
      ####
      # attribute coding (common options -- relies on option ordering)

cfg/trisoup-raht-ctc-lossy-geom-lossy-attrs.yaml

@@ -9,20 +9,18 @@ categories:
 
      ##
      # geometry parameters (trisoup)
-     - geometryCodec: 2
      - ctxOccupancyReductionFactor: 3
      - neighbourAvailBoundaryLog2: 8
      - intra_pred_max_node_size_log2: 6
      - inferredDirectCodingMode: 0
-     - triSoupDepth: ${test-depth}
-     - triSoupIntToOrigScale: '$eval{ 1 << ( ${src-geometry-precision} - ${test-depth} ) }'
-     - triSoupLevel:
-         r01: '$eval{ ${test-depth} - 4 }'
-         r02: '$eval{ ${test-depth} - 3 }'
-         r03: '$eval{ ${test-depth} - 3 }'
-         r04: '$eval{ ${test-depth} - 3 }'
-         r05: '$eval{ ${test-depth} - 2 }'
-         r06: ${test-depth}
+     - positionQuantizationScale: '$eval{ 1 / (1 << ( ${src-geometry-precision} - ${test-depth} )) }'
+     - trisoup_node_size_log2:
+         r01: 4
+         r02: 3
+         r03: 3
+         r04: 3
+         r05: 2
+         r06: 0
 
      ####
      # attribute coding (common options -- relies on option ordering)

doc/README.options.md

@@ -111,19 +111,6 @@ attribute coding, as if they had never been configured.
 Geometry coding
 ---------------
 
-### `--geometryCodec=1|2`
-Selects the geometry coding method.  Both available methods use octree
-coding as a base, where points are represented by the occupancy of an
-octree.  The trisoup method terminates the octree coding early and
-continues by encoding triangles which are subsequently voxelised to
-produce points.
-
-  | Value | Description      |
-  |:-----:| ---------------- |
-  | 0     | invalid          |
-  | 1     | octree only      |
-  | 2     | octree + trisoup |
-
 ### `--bitwiseOccupancyCoding=0|1`
 In octree geometry coding, there are both byte-wise and bit-wise tools to
 encode the occupancy data.  This option selects between the two methods.
@@ -163,19 +150,13 @@ The total number of contexts used is 256 >> *VALUE*.
 
 NB: the final standard is expected to define this factor as a constant.
 
-### `--triSoupDepth=INT-VALUE`
-Configures the maximum log2 node size of the geometry octree used by
-trisoup geometry coding.
-
-### `--triSoupLevel=INT-VALUE`
-Configures the log2 octree node size used for triangulation (the
-reconstructed surface) in trisoup geometry coding.
-
-### `--triSoupIntToOrigScale=REAL-VALUE`
-This option is the inverse of `positionQuantizationScale`, and is used to
-configure input scaling when trisoup geometry coding is enabled.
+### `--trisoup_node_size_log2=INT-VALUE`
+Controls the use of trisoup by setting the node size for triangle
+based surface reconstruction.  The trisoup method terminates the
+octree coding at the given node size and continues by encoding
+triangles which are subsequently voxelised to produce points.
 
-NB: this option will be removed in a future software version.
+A value of 0 disables the use of trisoup.
 
 
 Attribute coding

tmc3/TMC3.cpp

@@ -141,14 +141,6 @@ operator>>(std::istream& in, AttributeEncoding& val)
 }
 }  // namespace pcc
 
-namespace pcc {
-static std::istream&
-operator>>(std::istream& in, GeometryCodecType& val)
-{
-  return readUInt(in, val);
-}
-}  // namespace pcc
-
 namespace pcc {
 static std::ostream&
 operator<<(std::ostream& out, const AttributeEncoding& val)
@@ -162,18 +154,6 @@ operator<<(std::ostream& out, const AttributeEncoding& val)
 }
 }  // namespace pcc
 
-namespace pcc {
-static std::ostream&
-operator<<(std::ostream& out, const GeometryCodecType& val)
-{
-  switch (val) {
-  case GeometryCodecType::kOctree: out << "1 (Octree)"; break;
-  case GeometryCodecType::kTriSoup: out << "2 (TriSoup)"; break;
-  }
-  return out;
-}
-}  // namespace pcc
-
 //---------------------------------------------------------------------------
 // :: Command line / config parsing
 
@@ -298,12 +278,6 @@ ParseParameters(int argc, char* argv[], Parameters& params)
   (po::Section("Geometry"))
 
   // tools
-  ("geometryCodec",
-    params.encoder.gps.geom_codec_type, GeometryCodecType::kOctree,
-    "Controls the method used to encode geometry:\n"
-    "  1: octree (TMC3)\n"
-    "  2: trisoup (TMC1)")
-
   ("bitwiseOccupancyCoding",
     params.encoder.gps.bitwise_occupancy_coding_flag, true,
     "Selects between bitwise and bytewise occupancy coding:\n"
@@ -331,18 +305,10 @@ ParseParameters(int argc, char* argv[], Parameters& params)
      params.encoder.gps.geom_occupancy_ctx_reduction_factor, 3,
      "Adjusts the number of contexts used in occupancy coding")
 
-  // (trisoup) geometry parameters
-  ("triSoupDepth",  // log2(maxBB+1), where maxBB+1 is analogous to image width
-    params.encoder.gps.trisoup_depth, 10,
-    "Depth of voxels (reconstructed points) in trisoup geometry")
-
-  ("triSoupLevel",
-    params.encoder.gps.trisoup_triangle_level, 7,
-    "Level of triangles (reconstructed surface) in trisoup geometry")
-
-  ("triSoupIntToOrigScale",  // reciprocal of positionQuantizationScale
-    params.encoder.sps.donotuse_trisoup_int_to_orig_scale, 1.f,
-    "orig_coords = integer_coords * intToOrigScale")
+  ("trisoup_node_size_log2",
+    params.encoder.gps.trisoup_node_size_log2, 0,
+    "Size of nodes for surface triangulation.\n"
+    "  0: disabled\n")
 
   (po::Section("Attributes"))
 
@@ -430,31 +396,9 @@ ParseParameters(int argc, char* argv[], Parameters& params)
     return false;
   }
 
-  if (int(params.encoder.gps.geom_codec_type) == 0) {
-    err.error() << "Bypassed geometry coding is no longer supported\n";
-  }
-
-  // For trisoup, ensure that positionQuantizationScale is the exact inverse of intToOrigScale.
-  if (params.encoder.gps.geom_codec_type == GeometryCodecType::kTriSoup) {
-    params.encoder.sps.seq_source_geom_scale_factor =
-      1.0f / params.encoder.sps.donotuse_trisoup_int_to_orig_scale;
-  }
-
-  // TriSoup geometry is only enabled when trisoup depth > triangle_level.
-  // NB: this happens after the scale factor fudge above, since the user
-  //     believes they are configuring trisoup
-  if (params.encoder.gps.geom_codec_type == GeometryCodecType::kTriSoup) {
-    const auto& gps = params.encoder.gps;
-    int trisoupNodeSizeLog2 = gps.trisoup_depth - gps.trisoup_triangle_level;
-    if (trisoupNodeSizeLog2 <= 0) {
-      err.warn() << "TriSoup disabled when depth <= triangle level\n";
-      params.encoder.gps.geom_codec_type = GeometryCodecType::kOctree;
-    }
-  }
-
   // Certain coding modes are not available when trisoup is enabled.
   // Disable them, and warn if set (they may be set as defaults).
-  if (params.encoder.gps.geom_codec_type == GeometryCodecType::kTriSoup) {
+  if (params.encoder.gps.trisoup_node_size_log2 > 0) {
     if (!params.encoder.gps.geom_unique_points_flag)
       err.warn() << "TriSoup geometry does not preserve duplicated points\n";
 

tmc3/decoder.cpp

@@ -170,11 +170,10 @@ PCCTMC3Decoder3::decodeGeometryBrick(const PayloadBuffer& buf)
   arithmeticDecoder.setBuffer(int(buf.size()) - gbhSize, buf.data() + gbhSize);
   arithmeticDecoder.start();
 
-  if (_gps->geom_codec_type == GeometryCodecType::kOctree) {
+  if (_gps->trisoup_node_size_log2 == 0) {
     _currentPointCloud.resize(gbh.geom_num_points);
     decodeGeometryOctree(*_gps, gbh, _currentPointCloud, &arithmeticDecoder);
-  }
-  if (_gps->geom_codec_type == GeometryCodecType::kTriSoup) {
+  } else {
     decodeGeometryTrisoup(*_gps, gbh, _currentPointCloud, &arithmeticDecoder);
   }
 

tmc3/encoder.cpp

@@ -155,8 +155,8 @@ PCCTMC3Encoder3::compress(
   // recolouring
 
   // NB: recolouring is required if points are added / removed
-  bool recolourNeeded = _gps->geom_unique_points_flag
-    || _gps->geom_codec_type == GeometryCodecType::kTriSoup;
+  bool recolourNeeded =
+    _gps->geom_unique_points_flag || _gps->trisoup_node_size_log2 > 0;
 
   if (recolourNeeded) {
     recolour(
@@ -227,10 +227,6 @@ PCCTMC3Encoder3::encodeGeometryBrick(PayloadBuffer* buf)
   // the current node dimension (log2) encompasing maxBB
   int nodeSizeLog2 = ceillog2(maxBB + 1);
 
-  // todo(df): consider removal of trisoup_depth
-  if (_gps->geom_codec_type == GeometryCodecType::kTriSoup)
-    nodeSizeLog2 = _gps->trisoup_depth;
-
   GeometryBrickHeader gbh;
   gbh.geom_geom_parameter_set_id = _gps->gps_geom_parameter_set_id;
   gbh.geomBoxOrigin.x() = int(minPositions.x());
@@ -246,10 +242,9 @@ PCCTMC3Encoder3::encodeGeometryBrick(PayloadBuffer* buf)
   EntropyEncoder arithmeticEncoder(maxAcBufLen, nullptr);
   arithmeticEncoder.start();
 
-  if (_gps->geom_codec_type == GeometryCodecType::kOctree) {
+  if (_gps->trisoup_node_size_log2 == 0) {
     encodeGeometryOctree(*_gps, gbh, pointCloud, &arithmeticEncoder);
-  }
-  if (_gps->geom_codec_type == GeometryCodecType::kTriSoup) {
+  } else {
     encodeGeometryTrisoup(*_gps, gbh, pointCloud, &arithmeticEncoder);
   }
 
@@ -316,20 +311,10 @@ PCCTMC3Encoder3::quantization(const PCCPointSet3& inputPointCloud)
   // todo(df): allow overriding of minposition from CLI
   // todo(df): remove trisoup hack
   minPositions = PCCVector3D{0.0};
-  if (_gps->geom_codec_type == GeometryCodecType::kOctree)
+  if (_gps->trisoup_node_size_log2 == 0)
     computeMinPositions(inputPointCloud);
 
   PCCBox3<int32_t> clampBox{{0, 0, 0}, {INT32_MAX, INT32_MAX, INT32_MAX}};
-  if (_gps->geom_codec_type == GeometryCodecType::kTriSoup) {
-    // NB: Since trisoup forces the octree root node size, and the
-    //     quantiser above rounds half away from zero it is possible that
-    //     an input ranged [0,2**n) becomes [0,2**m], requiring an octree
-    //     root node size of 2**(m+1).
-    // todo(??): consider truncation towards zero in quantisation.
-    int32_t maxval = (1 << _gps->trisoup_depth) - 1;
-    clampBox = PCCBox3<int32_t>{{0, 0, 0}, {maxval, maxval, maxval}};
-  }
-
   if (_gps->geom_unique_points_flag) {
     quantizePositionsUniq(
       _sps->seq_source_geom_scale_factor, -minPositions, clampBox,

tmc3/geometry_octree_decoder.cpp

@@ -354,11 +354,6 @@ decodeGeometryOctree(
   // the current node dimension (log2)
   int nodeSizeLog2 = gbh.geom_max_node_size_log2;
 
-  // termination for trisoup
-  int terminalNodeSizeLog2 = 0;
-  if (gps.geom_codec_type == GeometryCodecType::kTriSoup)
-    terminalNodeSizeLog2 = gps.trisoup_depth - gps.trisoup_triangle_level;
-
   // push the first node
   fifo.emplace_back();
   PCCOctree3Node& node00 = fifo.back();
@@ -396,7 +391,7 @@ decodeGeometryOctree(
       decoder.beginOctreeLevel();
 
       // allow partial tree encoding using trisoup
-      if (nodeSizeLog2 == terminalNodeSizeLog2)
+      if (nodeSizeLog2 == gps.trisoup_node_size_log2)
         break;
     }
 

tmc3/geometry_octree_encoder.cpp

@@ -381,11 +381,6 @@ encodeGeometryOctree(
   // the initial node size is the root node's
   int nodeSizeLog2 = gbh.geom_max_node_size_log2;
 
-  // termination for trisoup
-  int terminalNodeSizeLog2 = 0;
-  if (gps.geom_codec_type == GeometryCodecType::kTriSoup)
-    terminalNodeSizeLog2 = gps.trisoup_depth - gps.trisoup_triangle_level;
-
   // this counter represents fifo.end() - fifoCurrLvlEnd().
   // ie, the number of nodes added to the next level of the tree
   int numNodesNextLvl = 0;
@@ -408,7 +403,7 @@ encodeGeometryOctree(
       encoder.beginOctreeLevel();
 
       // allow partial tree encoding using trisoup
-      if (nodeSizeLog2 == terminalNodeSizeLog2)
+      if (nodeSizeLog2 == gps.trisoup_node_size_log2)
         break;
     }
 

tmc3/geometry_trisoup_decoder.cpp

@@ -90,7 +90,7 @@ decodeGeometryTrisoup(
   pcc::ringbuf<PCCOctree3Node> nodes;
   decodeGeometryOctree(gps, gbh, pointCloud, arithmeticDecoder, &nodes);
 
-  int blockWidth = 1 << (gps.trisoup_depth - gps.trisoup_triangle_level);
+  int blockWidth = 1 << gps.trisoup_node_size_log2;
 
   uint32_t symbolCount;
   AdaptiveBitModel ctxTemp;
@@ -118,7 +118,7 @@ decodeGeometryTrisoup(
   }
 
   // Compute refinedVertices.
-  int32_t maxval = (1 << gps.trisoup_depth) - 1;
+  int32_t maxval = (1 << gbh.geom_max_node_size_log2) - 1;
   decodeTrisoupCommon(nodes, segind, vertices, pointCloud, blockWidth, maxval);
 }
 

tmc3/geometry_trisoup_encoder.cpp

@@ -54,7 +54,7 @@ encodeGeometryTrisoup(
   pcc::ringbuf<PCCOctree3Node> nodes;
   encodeGeometryOctree(gps, gbh, pointCloud, arithmeticEncoder, &nodes);
 
-  int blockWidth = 1 << (gps.trisoup_depth - gps.trisoup_triangle_level);
+  int blockWidth = 1 << gps.trisoup_node_size_log2;
 
   uint32_t symbolCount;
 
@@ -96,7 +96,7 @@ encodeGeometryTrisoup(
   }
 
   // Decode refinedVertices from segind and vertices.
-  int32_t maxval = (1 << gps.trisoup_depth) - 1;
+  int32_t maxval = (1 << gbh.geom_max_node_size_log2) - 1;
   decodeTrisoupCommon(nodes, segind, vertices, pointCloud, blockWidth, maxval);
 }
 

tmc3/hls.h

@@ -56,17 +56,6 @@ enum class PayloadType
 
 //============================================================================
 
-// Describes the geometry coding method.
-enum class GeometryCodecType
-{
-  // TMC3 lossless geometry codec using ocrees
-  kOctree = 1,
-  // TMC1 octree + triangulation
-  kTriSoup = 2,
-};
-
-//============================================================================
-
 enum class KnownAttributeLabel : uint32_t
 {
   kColour = 0,
@@ -165,10 +154,6 @@ struct SequenceParameterSet {
   // A value describing the scaling of the source positions prior to encoding.
   float seq_source_geom_scale_factor;
 
-  // orig_coords = integer_coords * intToOrigScale + intToOrigTranslation
-  // NB: this parameter has been replaced by seq_source_geom_scale_factor
-  float donotuse_trisoup_int_to_orig_scale;
-
   // NB: attributeSets.size() = num_attribute_sets
   std::vector<AttributeDescription> attributeSets;
 };
@@ -179,9 +164,6 @@ struct GeometryParameterSet {
   int gps_geom_parameter_set_id;
   int gps_seq_parameter_set_id;
 
-  // The geometry coding method
-  GeometryCodecType geom_codec_type;
-
   // Indicates that the GeometryBrickHeader contains a valid
   // geom_box_origin_xyz.
   int geom_box_present_flag;
@@ -214,11 +196,9 @@ struct GeometryParameterSet {
   // Maximum node size where intra prediction is enabled
   int intra_pred_max_node_size_log2;
 
-  // depth of voxels (reconstructed points) in trisoup geometry
-  int trisoup_depth;
-
-  // level of triangles (reconstructed surface) in trisoup geometry
-  int trisoup_triangle_level;
+  // size of triangle nodes (reconstructed surface) in trisoup geometry.
+  // a value of zero disables the feature
+  int trisoup_node_size_log2;
 };
 
 //============================================================================

tmc3/io_hls.cpp

@@ -187,7 +187,6 @@ write(const GeometryParameterSet& gps)
 
   bs.writeUe(gps.gps_geom_parameter_set_id);
   bs.writeUe(gps.gps_seq_parameter_set_id);
-  bs.writeUe(gps.geom_codec_type);
   bs.write(gps.geom_box_present_flag);
   bs.write(gps.geom_unique_points_flag);
   bs.write(gps.neighbour_context_restriction_flag);
@@ -196,11 +195,7 @@ write(const GeometryParameterSet& gps)
   bs.writeUe(gps.geom_occupancy_ctx_reduction_factor);
   bs.writeUe(gps.neighbour_avail_boundary_log2);
   bs.writeUe(gps.intra_pred_max_node_size_log2);
-
-  if (gps.geom_codec_type == GeometryCodecType::kTriSoup) {
-    bs.writeUe(gps.trisoup_depth);
-    bs.writeUe(gps.trisoup_triangle_level);
-  }
+  bs.writeUe(gps.trisoup_node_size_log2);
 
   bool gps_extension_flag = false;
   bs.write(gps_extension_flag);
@@ -220,7 +215,6 @@ parseGps(const PayloadBuffer& buf)
 
   bs.readUe(&gps.gps_geom_parameter_set_id);
   bs.readUe(&gps.gps_seq_parameter_set_id);
-  bs.readUe(&gps.geom_codec_type);
   bs.read(&gps.geom_box_present_flag);
   bs.read(&gps.geom_unique_points_flag);
   bs.read(&gps.neighbour_context_restriction_flag);
@@ -229,11 +223,7 @@ parseGps(const PayloadBuffer& buf)
   bs.readUe(&gps.geom_occupancy_ctx_reduction_factor);
   bs.readUe(&gps.neighbour_avail_boundary_log2);
   bs.readUe(&gps.intra_pred_max_node_size_log2);
-
-  if (gps.geom_codec_type == GeometryCodecType::kTriSoup) {
-    bs.readUe(&gps.trisoup_depth);
-    bs.readUe(&gps.trisoup_triangle_level);
-  }
+  bs.readUe(&gps.trisoup_node_size_log2);
 
   bool gps_extension_flag = bs.read();
   if (gps_extension_flag) {