Nikon D3300 Reference Manual page 189

3
Create a still copy.
Press 1 to create a still copy
of the current frame.
4
Save the copy.
Highlight Yes and press J
to create a fine-quality
(0 85) JPEG copy of the
selected frame.
A
Save Selected Frame
JPEG movie stills created with the Save selected frame option can not
be retouched. JPEG movie stills lack some categories of photo
information (0 172).
Recording and Viewing Movies 169