I have a PDF of a contour map of value Z for an area. For the same area, I have a set of points that I would like to match with Z values interpolated from this contour map. For an individual point, this can be "eyeballed" pretty easily, but I would like to do this for a few hundred points so I am looking for a more efficient way of doing this using for instance Google Earth, arcGIS, r, etc.
I am aware of the ability to overlay images in Google earth and draw lines on a map to export as kml files.
This seems like a reasonable place to start but it seems overly tedious to import these lines into r separately and write some algorithm to interpolate between the lines.
I am wondering what workflows and existing tools people are aware of for this type of problem since I have struggled to find much.
I am very new to working with GIS data.