Saving images

On Windows, I can save a CAPI image to a BMP using
GP:EXTERNALIZE-IMAGE and GP:WRITE-EXTERNAL-IMAGE or to a a WMF/EMF
using CAPI:WITH-EXTERNAL-METAFILE.  Is it possible to save an image to
any of the other supported image types (like PNG or JPG) without using
third-party libraries?

Thanks,
Edi.