Converting PCX to ...

I'm writing a reporting system and I have a problem. I need to insert PCXs into a PDF (using PDFLib), but it doesn't support PCXs. So, to get round the problem, I need to convert the PCXs to JPGs or GIFs Does anyone know of a piece of PHP that can do this inline, (by that I mean, can be called and run in PHP script), because the images will have additions and modifications on a regular basis; and they come as PCXs. Anyone? --BB