SIFTDescriptorSize Property OpenCvSharp Class Library
returns the descriptor size in float's (64 or 128)

Namespace:  OpenCvSharp.CPlusPlus
Assembly:  OpenCvSharp.CPlusPlus (in OpenCvSharp.CPlusPlus.dll) Version: 1.0.0.0 (1.0.0.0)
Syntax

public int DescriptorSize { get; }

Return Value

Type: Int32
See Also

Reference