What's the meaning of these two keywords?
An example:
struct CV_EXPORTS_W HOGDescriptor { public: enum { L2Hys=0 }; enum { DEFAULT_NLEVELS=64 };
CV_WRAP HOGDescriptor() : winSize(64,128), blockSize(16,16), blockStride(8,8),
cellSize(8,8), nbins(9), derivAperture(1), winSigma(-1),
histogramNormType(HOGDescriptor::L2Hys), L2HysThreshold(0.2), gammaCorrection(true),
nlevels(HOGDescriptor::DEFAULT_NLEVELS)
{}