Format doesn't guarantee function. Beware of bitmaps in vector clothing!
PDF and EPS are formats which should contain live, selectable text and clean, vector-based illustrations. But both can also contain bitmaps. Bitmaps should be saved in formats such as JPEG, TIFF or PNG, but scanners frequently use EPS or PDF instead. Unfortunately, bitmaps are "dead ends" for text and line illustrations, no matter what the file extension says: text and graphics locked in bitmapped artwork will have to be recreated if changes are needed or you want a clean, high-resolution appearance. There is no way to "un-bitmap" them. We are often asked to find "quick and easy" workarounds, such as overlaying text in white boxes. We strongly suggest you bite the bullet and let us recreate lost artwork.