ImageJ
ImageJ is a freeware available online. It is widely used in the medical imaging field for image treatment and analysis.
It allows, among others, to link DICOM (Digital Imaging and Communication in Medecine) images to JPEG images.
National Institutes of Health (NIH)link.
Direct link to ImageJ website.

Use ImageJ for activities
Use ImageJ alone
Open a DICOM image available
Open a DICOM image from a USB flash drive
Change an image windowing
Convert an opened image to JPEG
Show DICOM metadata
Analyze an image region content