unfortunately, there is no principled way of choosing this threshold even for a single image, since important edges generate a broad range of gradients, determined by contrast and degree of blur.

unfortunately, there is no principled way of choosing this threshold even for a single image (, since important edges
s v
generate a broad range of gradients,) (determined by contrast and degree of blur.)괄호 두부분이 싱글이미지를 둘다 수식하는것이 맞나요? (determined by contrast and degree of blur.) 부분이 수식해주는 부분이 좀 잘 안맞아서 헷갈리네요.