Revision history for FFmpeg-Command

0.04    Wed Aug 30
        Change default video_codec from h264 to mpeg4.

0.03    Mon Jul 31
        Skip an output option if its value is undef.

0.02    Mon Jul 31
        Added checking routine of output_options keys.
        Added output_options (title, author, comment, frame_rate)
        Renamed size options to frame_size.(You can still use 'size.')

0.01    Thu Jul 27
        First version, released on an unsuspecting world.