Recently I tried to recover mp4-files from an 32GB sd-card. A friend used it in his videocamera and
removed the card while the camera was on. I tried Recuva, testdisk, photorec, recuva, filescavenger,
cardrecovery, and zero assumption recovery.
Only these last 2 were able to recover about 30 GB of data. .Photorec
recovered about 1 GB but unusable files.
I used the demo version of cardrecovery and the demo version produced temporary files that
should be recoverable (to me they had
the correct filesize to be a videofile).
Opening these files with VLC-player showed that the file was unreadable.