How do I get descriptor from shape？ Will support?

[githubzhaoqian]

// New creates new face with the provided parameters.
func New(r image.Rectangle, d Descriptor) Face {
	return Face{r, d, []image.Point{}}
}

func NewWithShape(r image.Rectangle, s []image.Point, d Descriptor) Face {
	return Face{r, d, s}
}

How do I get descriptor from shape？
I didn't find a way to do it.
Will support?
I want to speed up by shape of opencv.

[UMUTBAYGUT]

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