mplayer -vf rotate=オプション ファイル

mplayer(1): movie player - Linux man page によると、 オプションは以下になる(英語)

Rotates the image by 90 degrees and optionally flips it. For values between 4-7 rotation is only done if the movie geometry is portrait and not landscape.

0    Rotate by 90 degrees clockwise and flip (default).

1    Rotate by 90 degrees clockwise.

2    Rotate by 90 degrees counterclockwise.

3    Rotate by 90 degrees counterclockwise and flip.