geometry: signal geometryCodecType in header

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.

tmc3/PCCTMC3Decoder.h

@@ -80,6 +80,11 @@ class PCCTMC3Decoder3 {
       std::cout << "Error: bistream version not supported!" << std::endl;
       return -1;
     }
+
+    // determine the geometry codec type
+    uint8_t geometryCodecRaw;
+    PCCReadFromBuffer<uint8_t>(bitstream.buffer, geometryCodecRaw, bitstream.size);
+
     uint8_t hasColors = 0;
     PCCReadFromBuffer<uint8_t>(bitstream.buffer, hasColors, bitstream.size);
     uint8_t hasReflectances = 0;
@@ -136,6 +141,10 @@ class PCCTMC3Decoder3 {
       return -1;
     }
 
+    // determine the geometry codec type
+    uint8_t geometryCodecRaw;
+    PCCReadFromBuffer<uint8_t>(bitstream.buffer, geometryCodecRaw, bitstream.size);
+
     uint64_t positionsSize = bitstream.size;
 
     decodePositionsHeader(bitstream, pointCloud);
@@ -189,6 +198,10 @@ class PCCTMC3Decoder3 {
       return -1;
     }
 
+    // determine the geometry codec type
+    uint8_t geometryCodecRaw;
+    PCCReadFromBuffer<uint8_t>(bitstream.buffer, geometryCodecRaw, bitstream.size);
+
     uint64_t positionsSize = bitstream.size;
     size_t depth;
     size_t level;

tmc3/PCCTMC3Encoder.h

@@ -143,6 +143,7 @@ class PCCTMC3Encoder3 {
 
     PCCWriteToBuffer<uint32_t>(PCCTMC3MagicNumber, bitstream.buffer, bitstream.size);
     PCCWriteToBuffer<uint32_t>(PCCTMC3FormatVersion, bitstream.buffer, bitstream.size);
+    PCCWriteToBuffer<uint8_t>(int(params.geometryCodec), bitstream.buffer, bitstream.size);
     PCCWriteToBuffer<uint8_t>(uint8_t(pointCloud.hasColors()), bitstream.buffer, bitstream.size);
     PCCWriteToBuffer<uint8_t>(uint8_t(pointCloud.hasReflectances()), bitstream.buffer,
                               bitstream.size);
@@ -184,6 +185,7 @@ class PCCTMC3Encoder3 {
     init();
     PCCWriteToBuffer<uint32_t>(PCCTMC3MagicNumber, bitstream.buffer, bitstream.size);
     PCCWriteToBuffer<uint32_t>(PCCTMC3FormatVersion, bitstream.buffer, bitstream.size);
+    PCCWriteToBuffer<uint8_t>(int(params.geometryCodec), bitstream.buffer, bitstream.size);
 
     if (int ret = quantization(inputPointCloud, params)) {
       return ret;
@@ -239,6 +241,7 @@ class PCCTMC3Encoder3 {
     init();
     PCCWriteToBuffer<uint32_t>(PCCTMC3MagicNumber, bitstream.buffer, bitstream.size);
     PCCWriteToBuffer<uint32_t>(PCCTMC3FormatVersion, bitstream.buffer, bitstream.size);
+    PCCWriteToBuffer<uint8_t>(int(params.geometryCodec), bitstream.buffer, bitstream.size);
 
     // Write out inputPointCloud file, just so that we can get it into the TMC1 pipeline.
     pcc::PCCPointSet3 tempPointCloud(inputPointCloud);