Cannot safe image on android with camera

sandro4912

I have the following Issue.

In my app I use QtMultimedia 5.14 and use its Camera class.

However when I take a picture and try to safe it I get a exception like this in the Application Output:

W libcamera_armeabi-v7a.so: qrc:/main.qml:55:19: QML Image: Cannot open: qrc:/data/user/0/org.qtproject.example.camera/files/IMG_00000015.jpg

Does it mean I don't have the user rights on android to safe?

The image safe code looks like this:

Camera {
    id: camera
}

//...

Connections {
    target: camera.imageCapture

    onImageSaved: {
        imagePaths.append({"path": path})
        listView.positionViewAtEnd();
    }
}

sierdzio

@sandro4912 said in Cannot safe image on android with camera:

qrc:/

QRC storage is read-only. Choose a different path.

App data location, cache location and temp locations are writable even if you do not get any storage permissions from your user.

sandro4912

stupid question. How can I change to a different path? What would be a valid path?

jsulm

@sandro4912 See https://doc.qt.io/qt-5/qstandardpaths.html using it you can get the paths @sierdzio already mentioned

sandro4912

@jsulm So I have to make a C++ class with QStandardPaths or is it available directly in QML?

jsulm

@sandro4912 There is something in Qt Labs: https://doc.qt.io/qt-5/qml-qt-labs-platform-standardpaths.html

sandro4912

I tryed it with the path but still no images. show up. Atleast the error does not appear anymore.

I changed the path here.

delegate: Image {
            height: 100
            //source: path
            source: Labs.StandardPaths.writableLocation(Labs.StandardPaths.ApplicationsLocation)
            fillMode: Image.PreserveAspectFit
        }

Full code:

import QtQuick 2.14
import QtQuick.Controls 2.14
import QtMultimedia 5.14
import Qt.labs.platform 1.1 as Labs

ApplicationWindow {
    visible: true

    id: root

    width: 1024
    height: 600



Rectangle {
    width: parent.width
    height: parent.height

    color: "black"

    VideoOutput {
        anchors.fill: parent
        source: camera
    }

    Camera {
        id: camera
    }

    ListModel {
        id: imagePaths
    }

    ListView {
        id: listView

        anchors.left: parent.left
        anchors.right: parent.right
        anchors.bottom: parent.bottom
        anchors.bottomMargin: 10

        height: 100

        orientation: ListView.Horizontal
        spacing: 10

        model: imagePaths

        delegate: Image {
            height: 100
            //source: path
            source: Labs.StandardPaths.writableLocation(Labs.StandardPaths.ApplicationsLocation)
            fillMode: Image.PreserveAspectFit
        }

        Rectangle {
            anchors.fill: parent
            anchors.topMargin: -10

            color: "black"
            opacity: 0.5
        }
    }

    Image {
        id: image
        anchors.fill: parent
    }

    Connections {
        target: camera.imageCapture

        onImageSaved: {
            imagePaths.append({"path": path})
            listView.positionViewAtEnd();
        }
    }

    Column {
        id: buttons

        anchors.top: parent.top
        anchors.right: parent.right
        anchors.margins: 10

        spacing: 10

        Button {
            id: shotButton

            text: "Take Photo"
            onClicked: {
                camera.imageCapture.capture();
            }
        }

        Button {
            id: playButton

            text: "Play Sequence"
            onClicked: {
                parent.parent.startPlayback();
            }
        }

        Button {
            id: clearButton

            text: "ClearSequence"
            onClicked: {
                imagePaths.clear()
            }
        }
    }

    property int _imageIndex: -1

    function startPlayback()
    {
        root.state = "playing"
        setImageIndex(0);
        playTimer.start();
    }

    function setImageIndex(i)
    {
        _imageIndex = i;

        if(_imageIndex >= 0 && _imageIndex < imagePaths.count) {
            image.source = imagePaths.get(_imageIndex).path;
        }
        else {
            image.source = "";
        }
    }

    Timer {
        id: playTimer

        interval: 200
        repeat: false

        onTriggered: {
            if (_imageIndex + 1 < imagePaths.count) {
                setImageIndex(_imageIndex + 1);
                playTimer.start();
            }
            else {
                setImageIndex(-1);
                root.state = "";
            }
        }
    }

    states: [
        State {
            name: "playing"
            PropertyChanges {
                target: buttons
                opacity: 0
            }
            PropertyChanges {
                target: listView
                opacity: 0
            }
        }
    ]

    transitions: [
        Transition {
            PropertyAnimation { properties: "opacity"; duration: 200; }
        }
    ]
}

}

SGaist

Hi,

Did you check that the folder exist ?
The path returned by QStandardPaths will be valid but you have to create some of these folders on first use.

sandro4912

What do you mean by that I have to create the standard folder?

SGaist

Check if the folder exist and if not well create it before creating the image file.

sandro4912

how could I achieve that in the code above?

SGaist

Create the folder ? I would do that in the C++ part on startup using QDir.

sandro4912

I think the path should already exist since it is the ApplicationsLocation.

I tryed this:

    Camera {
        id: camera
    }
    ListModel {
        id: imagePaths
    }

```
ListView {
    id: listView

    //...

    model: imagePaths

    delegate: Image {
        height: 100
        source: path
        fillMode: Image.PreserveAspectFit
    }

    Rectangle {
        anchors.fill: parent
        anchors.topMargin: -10

        color: "black"
        opacity: 0.5
    }
}


    ```
Image {
        id: image
        anchors.fill: parent
    }

    Connections {
        target: camera.imageCapture

        onImageSaved: {
            imagePaths.append({"path": Labs.StandardPaths.writableLocation(Labs.StandardPaths.ApplicationsLocation)})
            listView.positionViewAtEnd();
        }
    }

So my idea was when camera takes the picture i append in the model imagePaths the ApplicationsLocation Path.

Then when the delegate is used in the view it should load the Image from path.

If I try this it sayes QJSValue is not convertible to QDir

So what is wrong here?

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Cannot safe image on android with camera