Words coordinates in pdf file

Hi, I would like to read text and words coordinates from pdf file. It works ok, but I receice coordinates not corresponding to pdf. I suppose that engine in background creates image from pdf.
But how can I receive this preview image or at least resolution of this created image ?

I suppose that engine in background creates image from pdf.

Yes. => The good news that the difference between the returned coordinates and your coordinate system is a constant scaling factor. So you can use a few know positions to figure out what the scaling factor is for your setup (e. g. “1.5”) and then simply multiply all returned coordinates by it.