'Tearing' in playback & render

Discussion in 'SJ7 Star' started by Curtis, Dec 29, 2017.

  1. Curtis

    Curtis New Member

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    Greetings,

    I am a new SJ7 owner and have noticed some disturbing distortion (I assume this is classic 'tearing') during file playback on my PC laptop (older Asus A53S i7 w/2GB, w/NVIDIA GT540M) and after render on Vegas Pro 12.

    The distortion is a translucent horizontal line that either stays in the center (vertically) or quickly scrolls down the screen whenever there is a fast pan or tilt. My laptop is [supposed to be] capable of 720P @ 60Hz refresh rate. I cannot play the files back directly on my TV as i am waiting on a mini-to-full HDMI adapter.

    I am concerned that I cannot determine if this distortion is common to the camera or only my playback hardware? I do NOT see this when watching HD YouTube videos.

    Is this common? Are there ways to prevent it? Does the tearing only exist on my screen, or will it be manifested in YouTube videos, as well? (A test upload shows the tearing on my viewing of it on YouTube). I

    Thanks!

    Also, if anyone can tell me what 'Gimbal Control' does? I use the camera with Feiyu Tech G4S. Any effect?

    Curtis
     
  2. Jason

    Jason Moderator

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    What are your camera settings and can you post the link to the video - it's hard to comment on something we haven't seen. Is the upload the original video off the camera or one out of Vegas Pro?

    I believe that the Gimbal Control is for the SJCAM Gimbal to be able to stop/start recording easily when using it.
     
  3. Curtis

    Curtis New Member

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    Thanks for the reply, Jason.

    It was the first day that I had used the camera, and i was learning both it and the FT-G4S Gimbal at the same time, so I'm not certain of the exact settings other than i know it was at 720P 30FPS and I know the stabilization was off.

    The raw clip exhibits the distortion when played from a location on my laptop hard drive over Media Player, as does the rendered YouTube-ready file.

    Here is a link to the unlisted test video on YouTube. The output render settings were according to YouTube's Advanced Encoding Settings suggestion page. Please pardon the content but you can see the distortion when I pan or tilt quickly. If you cannot, then I can assume the issue is with my computer hardware/monitor.



    Thank you for your assistance & advice.

    Curtis
     
    Last edited: Dec 29, 2017
  4. Jason

    Jason Moderator

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    I see something at about 17 seconds, 51 seconds, 1 minuite. These are when the camera is tilting, panning and spinning fast.

    I think this is down to the panning and tilting movement being too fast and is an effect of the rolling shutter called jello.

    At 30 frames a second the camera reads the sensor 30 times a second. Each time it reads it it can't read it all at the same time but has to start at the top and work down reading one line at a time. If their is alot of movement (e.g. fast panning) then it can happen that by there is enough movement as its scanning one line to the next that the image moves part way through a frame making it look as if it's a different frame.

    Another way to see this is to hold the camera still with a bus or train driving past at speed. You might notice that the vertical lines of the windows look slanted when you examine each frame.
     
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  5. Curtis

    Curtis New Member

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    So this is an artifact common to all action cameras at low frame rates? I did shootbsome clips yesterday at 720 60fps and it seemed to tame the distortion quite a bit, though during very fast pans there was a slightly imperceptible instability.

    So there simple solution is a higher desperate?

    Does stabilization, distortion correction, video quality or sharpness settings seem to have any effect?

    It semantic me I have seen lots of action Cam footage that doesn't show those kinds of artifacts, is that because they Max their frame rates?

    Thanks for your help!

    C
     
  6. RBEmerson

    RBEmerson Humbled by events

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    I jumped around a bit in the playback, but, overall, I didn't find anything that suggests tearing. There is pixelation, but that's due to YouTube's compression "feature". Otherwise, I don't see anything, in the YouTube playback, that's objectionable.
     

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