QML won't save camera settings

[Pixtar]

Hi all,

I am using Qt5.2.1 (GCC 4.8, armeabi-v7a) at Windows8.1(x64) and a Samsung Galaxy S4 Mini with Android 4.2.2.

I tried to compile the qml example "qdeclarative-camera" and it worked to start the app with the smartphone and save images.

I tried also to modify the source to test some settings like changing exposuretime, iso, focus, contrast, etc.

Whatever I tried to change - contrast, iso or saturation - nothing happened.

What states or status do the camera should have to save the settings? Does it need to be stopped? Does it need a special captureMode? Are the settings reset by the function searchAndLock? Is it a bug at Qt5.2.1? Is Samsung blocking such functions? Do I need special variables in the pro-file like MOBILITY or TARGET.CAPABILITY?

It's very annoying, that I can't find any hint to solve the problem on my own.

Any hint is appreciated.

Greetings,
Pixtar

[wysota]

What do you mean by "save the settings"? save them where?

[Pixtar]

What do you mean by "save the settings"? save them where?

I mean the simple fact, when I'm using i.e. this little snippet:

camera.imageProcessing.saturation = 1
console.debug( camera.imageProcessing.saturation )
The output is 0 instead of 1.

I'm facing this problem with all settings:

camera.imageProcessing.contrast = 1
console.debug( camera.imageProcessing.contrast)
The output is 0 instead of 1.

[wysota]

Have you tried setting the values by declaring them directly in the QML document?

[Pixtar]

Wysota I don't know exactly what you mean, but I've tried the following:



Item{
Camera {
id: camera
imageProcessing.saturation: 1.0
imageProcessing.contrast: 1.0
....

imageCapture {
onImageSaved: {
console.debug( camera.imageProcessing.contrast )
}
}
}
}


I also tried it with a gui element:


Rectangle{
property Camera camera
id: mainRectangle
Slider{
id: contrastSpin
minimumValue: -10.0
maximumValue: 10.0
value: 1
stepSize: 1
onValueChanged: {
camera.imageProcessing.contrast = value/10.0
}
}
}

[wysota]

Maybe your camera simply does not allow modifying those values. At least the first approach should have worked otherwise.

[Pixtar]

For integrity here the main.cpp:


#include <QGuiApplication>
#include <QQmlComponent>
#include <QQmlContext>
#include <QObject>
#include <QQuickItem>
#include <QQuickView>
#include <QQuickImageProvider>
#include <QVariant>
#include <QCamera>

int main( int argc, char *argv[] ){
QGuiApplication app( argc, argv );

QQuickView view;

view.setResizeMode( QQuickView::SizeRootObjectToView );
view.setSource( QUrl("qrc:///QML/main.qml") );

QObject *item = view.rootObject( );

view.show( );
return app.exec( );
}


An here the code for main.qml:


import QtQuick 2.2
import QtMultimedia 5.2
import QtQuick.Layouts 1.1
import QtQuick.Controls 1.1
import QtQuick.Dialogs 1.1
import "qrc:///QML"

Item {
focus: true
visible: true
id: item
Camera {
id: camera
captureMode: Camera.CaptureStillImage
imageProcessing.saturation: -1.0
imageProcessing.contrast: -1.0
}

Rectangle{
id: rectangleImage
visible: true
ColumnLayout{
spacing: 10

Button{
id: menuButton
text: "Check Camera"
onClicked: {
camera.imageProcessing.contrast = -1.0
console.debug( camera.imageProcessing.contrast )
}
}

VideoOutput {
id: output
source: camera
focus : visible
visible: true
autoOrientation: true

anchors.fill: parent

x: parent.height > parent.width ? 0 : parent.width/2*2
y: parent.height > parent.width ? parent.height/2*2+5 : 0

height: parent.height > parent.width ? parent.height/2 : parent.height/2
width: parent.height > parent.width ? parent.width/2 : parent.width/2
}
}
}
}