We encourage the following procedure for content creation: Quicktime picture starting 10 seconds before first frame of action (FFOA) with a sync pop (both visual and audible) 2 seconds before FFOA. When printing your content into the Dolby Atmos VR Production Suite start capture 8 seconds before FFOA. After transcode and muxing of audio bitstream to the MP4 video file, use Dolby Media Generator to trim the start of the file to the FFOA - 

Quicktime start : 00:59:50:00 

Picture Start mark : 00:59:52:00 

Sync Pop : 00:59:58:00 

FFOA : 01:00:00:00 

dmg -i INPUTVIDEOFILE.mp4 --trim-start 00:00:02 -o OUTPUTVIDEOFILE.mp4 

dmg -i MP4_WRAPPED_EC3.mp4 --audio-passthru --videopassthru-file OUTPUTVIDEOFILE.mp4 -o OUTPUTVIDMUX.ATMOS.mp4 

dmg -i OUTPUTVIDMUX.ATMOS.mp4 --trim-start 00:00:08 -o OUTPUTMUXEDATMOSFILE.mp4 

Your Dolby Atmos for Virtual Reality Muxed MP4 now starts at the FFOA and can be auditioned using Dolby VR Player application for Windows.