vlad the large

I'm having the same problem with a large number of recovered jpgs. The odd thing is that the thumbnails were all recovered, but any of the larger files 1.5Mb + are saying they are missing their headers. I tried to look around and find something that might be able to recover the files but the one app I found couldnt find a marker to reinstate the header. I have about 8Gb of jpgs that need to be recovered. Does anyone have any additional recommendations on how to proceed?