Skip to content
  • Categories
  • Recent
  • Tags
  • Popular
  • Users
  • Groups
  • Search
  • Get Qt Extensions
  • Unsolved
Collapse
Brand Logo
  1. Home
  2. Qt Development
  3. QML and Qt Quick
  4. QML Camera : Noise appears on the camera image at high load
Forum Updated to NodeBB v4.3 + New Features

QML Camera : Noise appears on the camera image at high load

Scheduled Pinned Locked Moved Solved QML and Qt Quick
3 Posts 2 Posters 398 Views 2 Watching
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • T Offline
    T Offline
    T_T.0912
    wrote on last edited by
    #1

    Hi all, I'm creating a camera display app.

    I have a problem. That is, if you put a load on the CPU, noise will be generated in the camera image.

    What kind of noise is that the camera image becomes black for a moment.
    But, this problem did not occur with the function alone.

    I want to constantly animate and swipe within this app.
    However, if you do that, the camera image will not be displayed correctly.
    I took measures such as using OpenCV, but it has not been a fundamental solution.
    (I want to use two or more camera images, but this method is too heavy to use.)

    How do you solve such problems?

    The source code below shows the camera image.

    Camera{
         id: cam1Stream
         deviceId: QtMultimedia.availableCameras[0].deviceId
    }
    VideoOutput{
         id: content
         width: base.width; height: base.height
         source: cam1Stream
     }
    

    Development environment
    Qt Creator version: 4.5.1
    Qt version: 5.10.1
    CPU used: imx8m
    use camera: 1280x960 YUV Format

    rrlopezR 1 Reply Last reply
    0
    • T T_T.0912

      Hi all, I'm creating a camera display app.

      I have a problem. That is, if you put a load on the CPU, noise will be generated in the camera image.

      What kind of noise is that the camera image becomes black for a moment.
      But, this problem did not occur with the function alone.

      I want to constantly animate and swipe within this app.
      However, if you do that, the camera image will not be displayed correctly.
      I took measures such as using OpenCV, but it has not been a fundamental solution.
      (I want to use two or more camera images, but this method is too heavy to use.)

      How do you solve such problems?

      The source code below shows the camera image.

      Camera{
           id: cam1Stream
           deviceId: QtMultimedia.availableCameras[0].deviceId
      }
      VideoOutput{
           id: content
           width: base.width; height: base.height
           source: cam1Stream
       }
      

      Development environment
      Qt Creator version: 4.5.1
      Qt version: 5.10.1
      CPU used: imx8m
      use camera: 1280x960 YUV Format

      rrlopezR Offline
      rrlopezR Offline
      rrlopez
      wrote on last edited by
      #2

      @T_T-0912 Hi, what you are seeing is basically that QML UI is a single thread. If you force this thread too much (which you are doing with image processing to show image and doing animations on top of it) it will consume a lot of CPU. I recommend processing the image in a different thread (not using QML) for this if performance is an issue. I work for a company where we use boards with limited resources and created a product to solve these issues:

      https://developer.ridgerun.com/wiki/index.php?title=Gstreamer_QT_Overlay

      Lic-Ing. Rodrigo Lopez Gonzalez
      Embedded Software Engineer
      RidgeRun Engineering Ltd.
      www.ridgerun.com
      Email: rodrigo.lopez@ridgerun.com

      1 Reply Last reply
      0
      • T Offline
        T Offline
        T_T.0912
        wrote on last edited by
        #3

        Thank you for the answer.
        I will try to solve it in another way.

        1 Reply Last reply
        0

        • Login

        • Login or register to search.
        • First post
          Last post
        0
        • Categories
        • Recent
        • Tags
        • Popular
        • Users
        • Groups
        • Search
        • Get Qt Extensions
        • Unsolved