I am running this command
ffmpeg -i "video_in.mp4" -vf "movie=watermark.png [watermark]; [in][watermark] overlay=main_w/2-overlay_w/2:main_h/2-overlay_h/2 [out]" outputvideo.mp4
also tried
/usr/local/bin/ffmpeg -i "video_in.mp4" -vf "movie=watermark.png [watermark]; [in][watermark] overlay=main_w/2-overlay_w/2:main_h/2-overlay_h/2 [out]" outputvideo.mp4
Error : unrecognized option '-vf' in ffmpeg