About: http://webisa.webdatacommons.org/439578124

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	For the grayscale image, this gradient is a vector, one component of which is a derivative of brightness along X-axis, and the other is a derivative of a brightness along Y-axis.
http://www.w3.org/ns/prov#wasQuotedFrom	svgopen.org