PhotoRec is file data recovery software designed to recover lost pictures (Photo Recovery) from digital camera memory and lost files including video, documents and archives from Hard Disks and CDRom. PhotoRec ignores the filesystem and goes after the underlying data, so it'll work even if your media's filesystem is severely damaged or formatted. PhotoRec is safe to use, it will never attempt to write to the drive or memory support you are about to recover from. Recovered files are instead written in the directory from where you are running the PhotoRec program.
PhotoRec has been successfully tested with the following Digital Camera
Canon EOS300D, 10D
HP PhotoSmart 620, 850, 935
Nikon CoolPix 775, 950, 5700
Olympus C350N, C860L, Mju 400 Digital, Stylus 300
Casio Exilim EX-Z 750