can this function include in media player classic?

set any frame of mp4 video as a mp4 file thumbnail and very quickly
example
while playing video if i stop on frame at 0.53sec and i want to set this frame as a mp4 file thumbnail
then i just right click on stopped video frame and there will be option like set as thumbnail of file
can this be done
or any other method

Not possible. The player is not involved in thumbnail generation in Explorer.

Admin wrote:Not possible. The player is not involved in thumbnail generation in Explorer.

any other player that can be used for the purpose?

No players that can do this.

You can make screenshot with the player. Save it as cover.jpg file. Then remux your MP4 file into MKV file with MkvToolNix application. Then you can add cover file as attachment.

The Icaros thumbnail plugin will then use the embedded cover for thumbnail.