Quantization in mesh compression

A method of mesh encoding, comprising:

• determining (i) a position prediction of a current vertex of a base mesh associated with a mesh in a current mesh frame and (ii) a motion field prediction of the current vertex of the base mesh;
• quantizing (i) a position prediction residue for the position prediction of the current vertex to generate a quantized position prediction residue based on a first quantization step value, and (ii) a motion field prediction residue for the motion field prediction of the current vertex to generate a quantized motion field prediction residue based on a second quantization step value, the second quantization step value being determined based on a function of the first quantization step value;
• and
• entropy coding (i) the quantized position prediction residue for the position prediction of the current vertex, and (ii) the quantized motion field prediction residue for the motion field prediction of the current vertex.

A non-transitory computer-readable storage medium storing instructions which, when executed by a processor, cause the processor to perform a method of encoding a bitstream comprising:

• determining (i) a position prediction of a current vertex of a base mesh associated with a mesh in a current mesh frame and (ii) a motion field prediction of the current vertex of the base mesh;
• quantizing (i) a position prediction residue for the position prediction of the current vertex to generate a quantized position prediction residue based on a first quantization step value, and (ii) a motion field prediction residue for the motion field prediction of the current vertex to generate a quantized motion field prediction residue based on a second quantization step value, the second quantization step value being determined based on a function of the first quantization step value;
• entropy coding (i) the quantized position prediction residue for the position prediction of the current vertex, and (ii) the quantized motion field prediction residue for the motion field prediction of the current vertex in the bitstream;
• and
• transmitting the encoded bitstream.