How to design a custom videoOutput?

[stereoMatching]

The videoOutput I mean is

Rectangle {
        width: 320
        height: 240
 
        Camera{
            id: camera
        }
 
        VideoOutput {
            id: videoOutput
 
            anchors.fill: parent
            source: camera
        }    
 
        GammaAdjust {
            id: gammaAdjust
 
            anchors.fill: videoOutput
            source: videoOutput
            gamma: 0.5
        }
    }

Rectangle {
        width: 320
        height: 240
     
        Camera{
            id: camera
        }
     
        VideoOutput {
            id: videoOutput
     
            anchors.fill: parent
            source: camera
        }    
     
        GammaAdjust {
            id: gammaAdjust
     
            anchors.fill: videoOutput
            source: videoOutput
            gamma: 0.5
        }
    }

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How could design the videoOutput by myself?
Maybe this is the fastest and easiest way to save the
image after postprocessing,thanks