Data text information sometimes cannot be recognized by VDE/PIOE (extract, delete, color) even though it is vector data.
This could occur because VDE/PIOE does not look into the content in a VDO (Virtual Document Overlay), if the text is in a VDO, VDE does not know its existence.
Adding the profile option
PDFIN_USEOVERLAYS=NO
Switching off VDO creation makes the text appear in the VDD (Virtual Dynamic Document), and VDE can detect the text (color, extract) from there.
Whether to create VDOs
Whether to create a VDO at the first appearance of an object
The objects for which VDOs should be created. Vector mode only
UPDATED: February 24, 2017