I'm trying to modify src/control/video.c to set contrast, brightness and other settings using libvlc: i've tried with this function but nothing happens... void libvlc_video_set_contrast( libvlc_media_player_t *p_mi, float contrast, libvlc_exception_t *p_e ) { vout_thread_t *p_vout = GetVout( p_mi, p...