JooVuu X: 1080p/30 HDR and FOV

Discussion in 'JooVuu' started by dirkzelf, Nov 9, 2017.

  1. dirkzelf

    dirkzelf Well-Known Member

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    I'd like to change FOV to 120 or 90 degree in HDR / 1080p/30 mode, but for some reason it's stuck on 155??

    Is that a bug, or for a good reason?
     
  2. Kip

    Kip Active Member

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    Are you trying to change it in the app or via PC? I vaguely remember the app displaying a message telling you not to change FOV when using HDR mode. I don't know the reasoning behind it, however.
     
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  3. lacibaci

    lacibaci Well-Known Member

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    Changing FOV to 120 or 90 degrees just crops the center from the sensor right?
     
  4. dirkzelf

    dirkzelf Well-Known Member

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    That seems obvious, because there is no optical zoom.
     
  5. dirkzelf

    dirkzelf Well-Known Member

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    I hadn't thought of that, but I just tried, and whatever FOV you enter in HDR mode, it always stuck on 155..... d@mmit... it seems to accept the change in the PC app, but after reboot the camera doesn't take kindly to my request.... :eek:
     
  6. lacibaci

    lacibaci Well-Known Member

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    So there is really no advantage of using narrower FOV?
     
  7. dirkzelf

    dirkzelf Well-Known Member

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    In terms of sharpness you mean? Maybe, maybe not, I haven't really ever tested the difference. But I figure there is a way to use the whole sensor array / area to get better (larger) license plates.

    I don't think the JooVuu uses digital zoom, or crop if you will.

    Anyone care to weigh in?
     
  8. lacibaci

    lacibaci Well-Known Member

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    That's why I asked. With the fixed lens the whole notion of adjustable FOV is kind of pointless as far as image quality goes. You will not get more pixels per inch even if you chose 90 degree FOV.
     
  9. dirkzelf

    dirkzelf Well-Known Member

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    Like I said, it sounds logical, and I'm planning to test it, but my question actually is:

    "why CAN we change FOV in all modes, but NOT in HDR....??"
     
  10. jokiin

    jokiin Well-Known Member Manufacturer

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    I'd expect it is something to do with how HDR works in using multiple frames to create the image
     
  11. dirkzelf

    dirkzelf Well-Known Member

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    Is HDR using double frames to create better endresult-frame ?!? Like those new dual camera's on smartphones (one B/W, one color)??
     
  12. jokiin

    jokiin Well-Known Member Manufacturer

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    I'm not sure what method Ambarella are using but I think it's likely related
     
  13. Kip

    Kip Active Member

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    I've got a feeling that in 1080p mode the camera uses more of the (1440p) sensor and resizes the image down to 1080p if you use the widest FOV setting. If you select say 120 FOV, it may only use 1920x1080 pixels to record without any resizing. This would explain why when I use 2560x1080 @155 FOV, the amount of visible dashboard (width wise) doesn't change when swapping to a 1920x1080 @155 FOV mode. Try different resolutions at different FOV's with it mounted in the car and you'll see what I mean. If you use the very narrow FOV setting, it probably will crop off pixels and then upscale to meet the selected resolution. The only advantage that I can tell would be that the camera could allocate all of the available bitrate to a small section of the frame.
     
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