m42634/attr: restrict numberOfNearestNeighborsInPrediction to 4

This commit reduces the number of nearest neighbours used in attribute
prediction to 4 from 8 in order to reduce memory usage.

Extracted-from: http://wg11.sc29.org/svn/repos/MPEG-I/Part5-PointCloudCompression/CE/CE0/CE0.1/trunk@1357


Reintegrated-by:  <dflynn@blackberry.com>

cfg/lossless-geom-lossy-texture/tollbooth_q1mm/r02/encoder.cfg

@@ -3,7 +3,7 @@
 mode: 2
 colorTransform: 1
 positionQuantizationScale: 1
-numberOfNearestNeighborsInPrediction: 8
+numberOfNearestNeighborsInPrediction: 4
 levelOfDetailCount: 9
 searchRange: 0
 dist2: 134217728 33554432 8388608 2097152 524288 131072 32768 8192 0

cfg/lossless-geom-lossy-texture/tollbooth_q1mm/r03/encoder.cfg

@@ -3,7 +3,7 @@
 mode: 2
 colorTransform: 1
 positionQuantizationScale: 1
-numberOfNearestNeighborsInPrediction: 8
+numberOfNearestNeighborsInPrediction: 4
 levelOfDetailCount: 9
 searchRange: 0
 dist2: 134217728 33554432 8388608 2097152 524288 131072 32768 8192 0

cfg/lossless-geom-lossy-texture/tollbooth_q1mm/r04/encoder.cfg

@@ -3,7 +3,7 @@
 mode: 2
 colorTransform: 1
 positionQuantizationScale: 1
-numberOfNearestNeighborsInPrediction: 8
+numberOfNearestNeighborsInPrediction: 4
 levelOfDetailCount: 9
 searchRange: 0
 dist2: 134217728 33554432 8388608 2097152 524288 131072 32768 8192 0

cfg/lossless-geom-lossy-texture/tollbooth_q1mm/r05/encoder.cfg

@@ -3,7 +3,7 @@
 mode: 2
 colorTransform: 1
 positionQuantizationScale: 1
-numberOfNearestNeighborsInPrediction: 8
+numberOfNearestNeighborsInPrediction: 4
 levelOfDetailCount: 9
 searchRange: 0
 dist2: 134217728 33554432 8388608 2097152 524288 131072 32768 8192 0

cfg/lossless-geom-lossy-texture/tollbooth_q1mm/r06/encoder.cfg

@@ -3,7 +3,7 @@
 mode: 2
 colorTransform: 1
 positionQuantizationScale: 1
-numberOfNearestNeighborsInPrediction: 8
+numberOfNearestNeighborsInPrediction: 4
 levelOfDetailCount: 9
 searchRange: 0
 dist2: 134217728 33554432 8388608 2097152 524288 131072 32768 8192 0

tmc3/PCCTMC3Common.h

@@ -44,7 +44,7 @@
 namespace pcc {
 const uint32_t PCCTMC3MagicNumber = 20110904;
 const uint32_t PCCTMC3FormatVersion = 1;
-const uint32_t PCCTMC3MaxPredictionNearestNeighborCount = 8;
+const uint32_t PCCTMC3MaxPredictionNearestNeighborCount = 4;
 const uint32_t PCCTMC3Diff1AdaptiveDataModelCount = 512;
 const uint32_t PCCTMC3AdaptiveDataModelAlphabetMaxSize = 2047;
 

tmc3/TMC3.cpp

@@ -186,7 +186,7 @@ bool ParseParameters(int argc, char *argv[], Parameters &params) {
      "Attribute's todo(kmammou)")
 
   ("numberOfNearestNeighborsInPrediction",
-     params_attr.numberOfNearestNeighborsInPrediction, size_t(8),
+     params_attr.numberOfNearestNeighborsInPrediction, size_t(4),
      "Attribute's maximum number of nearest neighbors to be used for prediction")
 
   ("levelOfDetailCount",
@@ -219,14 +219,21 @@ bool ParseParameters(int argc, char *argv[], Parameters &params) {
   //  - validate that quantizationSteps, dist2
   //    of each attribute contain levelOfDetailCount elements.
   for (const auto &attr : params.encodeParameters.attributeEncodeParameters) {
-      int lod = attr.second.levelOfDetailCount;
+    int lod = attr.second.levelOfDetailCount;
 
-      if (attr.second.dist2.size() != lod) {
-        err.error() << attr.first << ".dist2 does not have " << lod << " entries\n";
-      }
-      if (attr.second.quantizationSteps.size() != lod) {
-        err.error() << attr.first << ".quantizationSteps does not have " << lod << " entries\n";
-      }
+    if (attr.second.dist2.size() != lod) {
+      err.error() << attr.first << ".dist2 does not have " << lod << " entries\n";
+    }
+    if (attr.second.quantizationSteps.size() != lod) {
+      err.error() << attr.first << ".quantizationSteps does not have " << lod << " entries\n";
+    }
+    if (attr.second.numberOfNearestNeighborsInPrediction >
+        PCCTMC3MaxPredictionNearestNeighborCount)
+    {
+      err.error() << attr.first
+        << ".numberOfNearestNeighborsInPrediction must be less than "
+        << PCCTMC3MaxPredictionNearestNeighborCount << "\n";
+    }
   }
 
   // check required arguments are specified