Importing photos with Virb edit

Hi All ,Im looking for a bit of help importing photos using the garmin virb edit,I have downloaded and created a video and would like to put some photos at the end ,the photos I have taken will not import,these were taking with just a digital camera,some photos taken by a friend with a phone camera will import no problem at all,am i missing something,do they have to be resized,converted etc,any help would be great,regards,eddie....