win2pdfd.exe makesearchable "sourcefile" "destfile"
Recognizes text from images and graphics using Optical Character Recognition (OCR) from "sourcefile", and saves the text information in an invisible text layer in "destfile" to make the PDF searchable. If "sourcefile" and "destfile" are the same file, the file is modified in place.
Requires that the Win2PDF Desktop Searchable component is installed (separate download from Win2PDF).
Any file names that contain spaces must be enclosed with quotation marks. The "sourcefile" can be a local file path, or an web address (URL) to an existing PDF.
Returns 0 on success, and a Windows system error code on failure.