void clear() { m_data.clear(); m_dims = FgVect2UI(0); }
// WARNING: This does not adjust any existing image data, just allocated dimensions and memory: void resize(uint wid,uint hgt) { m_dims = FgVect2UI(wid,hgt); m_data.resize(wid*hgt); }
FgVect2UI dims() const {return FgVect2UI(ncols,nrows); } // NB Order