Creating a xml photo gallery

I am wondering if there is a way to use data stored as part of the image (tag data?) like the title of the image and accompanying comments to display in the <caption></caption> section of the xml file.

right now I have php write the xml file in the following format
<gallery>
<image>
<url></url>
<caption></caption>
<width></width>
<height></height>
</image>
</gallery>

The php just pulls all the images from a folder so the gallery gets updated when I add images to the folder. Now I would like to know if that info from the file (the stuff you see when you right click the file to see its properties, then the summary) can be generated under the caption section. This way the captions can be automatically generated without me having to type it in for each image.

I am using this for our school website. It is for our staff page. I am hoping to just drop the images of the staff in a folder and have the page update that way and include the staff member name and their teaching assignment as part of the "title" and "comments" section of the tag data of the image.

Thanks

Darren