QML Camera works strange in Linux Framebuffer

[MintogoDeveloper]

Hi I develop some camera application on embedded environment.

Here is my develop environment and qt versoin

• Develop environment

• device : Odroid C2
• CPU : ARM 64
• OS: Ubuntu 18.04 minimal
• Qt : 5.9.5 build against to eglfs
• Camera : USB Web cam

I need to use QML Camera module on my app, so I added below code to test it.

import QtQuick 2.9
import QtQuick.Window 2.0
import QtMultimedia 5.9

Window {
id: window
visible: true
width: 1280
height: 800
title: qsTr("Hello World")

Item {
    id: item
    width: 640
    height: 480

    Camera {
        id: camera

        viewfinder.resolution: Qt.size(640, 480)
    }

    VideoOutput {
        source: camera
        anchors.fill: parent
        focus : visible
    }
}

}

above code is very simple camera viewer code.

In desktop environment, camera image is very cool and smooth.

but In my develop environment (Odroid C2 Ubuntu 64 eglfs)

camera image is broken like a tearing (please show attatced Images)

How can I resolve or reduce it?