zoo_station

Q: Frame Edge Artifact When Exporting 360

After exporting a 360 video out of Final Cut Pro (10.2.3), I notice a stitch artifact appear where the frames seam at 360˚/0˚. This is causing a black line 1-2 pixels wide to travel longitudinally from pole to pole, which can only be seen when the video is played on a HMD in a VR Player such as GoPro Player.

 

To test the issue, the same video was transcoded using iFFMpeg and the stitch is seamless, leading me to believe this is a bug with QuickTime, since both Compressor and FCP exhibit the exact same result after transcoding.

 

Is QuickTime killing pixels?

Final Cut Pro X, OS X El Capitan (10.11.5), null

Posted on Jul 20, 2016 12:19 AM

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Q: Frame Edge Artifact When Exporting 360

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  • by BenB,Helpful

    BenB BenB Jul 20, 2016 11:49 PM in response to zoo_station
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    Jul 20, 2016 11:49 PM in response to zoo_station

    Not a QT issue, but an issue with the Dashwood plugin.  I'd contact Dashwood.

     

    BTW, FCPX and Compressor and Motion all run on the AVFoundation now, not QT.  QT is relegated to playback these days.  Eventually it will vanish.

  • by zoo_station,

    zoo_station zoo_station Jul 20, 2016 11:55 PM in response to BenB
    Level 1 (8 points)
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    Jul 20, 2016 11:55 PM in response to BenB

    BenB, thanks for the note and QT clarification.

     

    I did not apply any Dashwood effects at the time, although I was  using the 360VR Viewer for monitoring in FCP, and it was occurring while exporting out of FCP and when transcoding the original file in Compressor.

     

    Can you further explain why Dashwood would also impact Compressor?

     

    Thanks

  • by BenB,Helpful

    BenB BenB Jul 21, 2016 6:35 AM in response to zoo_station
    Level 6 (9,816 points)
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    Jul 21, 2016 6:35 AM in response to zoo_station

    How were you using 360 video inside of FCPX?   It doesn't do that without the Dashwood plugin.  What was the source of this 360 video you were using?

  • by zoo_station,

    zoo_station zoo_station Jul 22, 2016 4:36 PM in response to BenB
    Level 1 (8 points)
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    Jul 22, 2016 4:36 PM in response to BenB

    I am testing FCPX's  capability of handling prestitched 360 stereo equirectangular, which doesn't necessarily require using Dashwood plugins since it's straight up video.

     

    FCP

     

    1. Transcode files from mp4 to ProRes before importing using iFFMPEG (depends on the format/resolution, since h.264 is limited to 2304x2304.)

    2. Import and drag to project

    3. Test playback with Dashwood 360VR Viewer looks good here, no stitching artifacts.

    4. Maybe create a proxy and do the same thing

    5. Export file both proxy and hires (UHD ProRes)

    6. Stitching artifact at vertical frame edge when playing in a viewer outside fcp

     

    Compressor

    1. Drag mp4 clip into compressor 1:1

    2. Export new clip UHD 16:9 and 1:1

    3. Stitching artifact

     

    Also, just curious: in the trial and error process, I found some h.264/.mp4 resolution limits.

     

    Why do these applications have a set limitation on the square aspect mp4 resolution at 2304x2304, and can Apple fix that easily? It impacts the workflow of FCPX for VR use cases and creates so many unnecessary steps.