XnView Frame

XnView Frame (.xnf) is a file that contains a reference to an external video file, and a frame in that file. In most or all cases, it contains a snapshot image of that frame. It is associated with the XnView graphics software (at least XnView MP).

An XNF file can be created by playing a video file in XnView MP, pausing it, right-clicking on it, and selecting "Extract current frame" from the menu.

Format details
An XNF file is a standard JFIF/JPEG file containing a still image of the relevant frame. It also has embedded XMP+RDF metadata containing the video file's name, and a frame number. The metadata includes an attribute similar to the following: xmlns:xnvmp="http://ns.xnview.com/xnf/1.0/"

There might be other XNF formats. The original proposal was different.

Software

 * XnView MP: Refer to XnView.