For Image, if you render it on map, you need to pass into the bounding box for make sure where it's located, so you can get the extent and do spatial query. Some image have its world file, you can directly read from it.
For Label, because we have many properties to effect where and how to draw the label, and after drawn on canvas it's not a feature again, so we cannot do spatial query for it.
Could you please let us know why you need to check the point position and the Image/Label bounding box? We want to discuss about whether we can implement that by other way.