Unlike many of the other Samsung photo frame devices, this particular device does not use a display link chipset and simply pushes JPG images onto the frame. Mini-monitor mode only receives JPG images over USB. The machine running frame manager software redraws the display and compresses in JPG format and appends the beginning of the JFIF with a 12 byte sequence where the middle 4 bytes indicate size of image. Other 8 bytes don't seem to change from frame to frame. No idea what they actually mean. On a linux machine, make sure that the USB device is not recognized as a mass-storage device but rather as a Vendor Specific class device. You can use the mode-switching script to do that below. Following, playusb takes jpg images and replays it on the photo frame screen.
libusb link
Originally, we thought this only worked for the Samsung SPF107H. Turns out there's more! Please let us know of any similar devices this works with. (May have to run as root)
Useful and related stuff
If you know of other known devices that use something similar or have general comments, please contact me or Matt Hirsch. And, thanks to szym.