How to start camera in qt ?

Golubev

I started making a camera and ran into the problem that I can't display an image when I use the desktop application on win 11. Even the Camera example doesn't work. maybe you need some permissions for win 11?

CaptureSession {
            id: captureSession
            videoOutput: videoOutput
            
            camera: Camera {
                id: camera
            }
            imageCapture: ImageCapture {
                id: imageCapture
                onErrorOccurred: function(requestId, error, message) {
                    console.log("Error occurred", requestId, error, message);
                }
                onImageCaptured: function(requestId, previewImage) {
                    console.log("Image captured", requestId, previewImage);
                }
                onImageSaved: function(requestId, path) {
                    console.log("Image saved", requestId, path);
                    TaskManager.attachPhotoToTask(taskId,path)
                    
                    loader.push("TaskEditDialogImages.qml",{taskId = taskId})
                }
            }
            
        }
        
        VideoOutput {
            id: videoOutput
            anchors {
                top: controlsRow.bottom
                bottom: parent.bottom
                left: parent.left
                right: parent.right
                margins: 10
            }
        }

Everything works on android, although it doesn't show the picture on some devices. Permissions in main.cpp I added. I use the Cmake file. I even added a check.

QCameraPermission cameraPermission;
    qApp->requestPermission(cameraPermission, [&](const QPermission &permission) {
        if (permission.status() == Qt::PermissionStatus::Granted) {
            qDebug() << "Camera permission granted";
        } else {
            qWarning() << "Camera permission denied!";
        }
 } );

when I click on the button, it returns an error : qml: Error occurred -1 1 Could not capture in stopped state

Button {
                id: captureButton
                implicitWidth: 50
                implicitHeight: 50
                radius: 30
                onClicked: {
                    captureSession.imageCapture.captureToFile(CameraManager.getPath());
                }
                Image {
                    id: photoIcon
                    source: "photoIcon.png"
                    anchors.fill: parent
                    anchors.centerIn: photoIcon
                }
            }

also use :

property bool isActive: StackView.view ? StackView.view.currentItem === cameraPage : false
    onIsActiveChanged: {
        console.log("Camera page active:", isActive)
        if (isActive) {
            camera.start()
        } else {
            camera.stop()
        }
    }

before opening, he writes that the camera starts and on the laptop itself it is visible with a light bulb.
please help me solve the problem

SGaist

Hi,

You should also add which version of Qt you are using.
Which brand of machine you are using, etc.

Golubev

@SGaist use Based on Qt 6.8.2 (MSVC 2022, x86_64) .Laptop Hp proBook 450 G9

jsulm

@Golubev said in How to start camera in qt ?:

Based on Qt 6.8.2 (MSVC 2022, x86_64)

Do you mean QtCreator is based on this Qt version or is this the Qt version you're using (this is not the same!)?

Golubev

@jsulm ( image)

I don't even know where to look, but it looks like it

( image)

jsulm

@Golubev said in How to start camera in qt ?:

I don't even know where to look

You should know what Qt version you installed. If you don't know when go to the Kit configuration in QtCreator and check what Qt version is set there.

Golubev

@jsulm This one ? ( image url)

I remembered I was installing 6.7.3

jsulm

@Golubev Can you try with the latest Qt6 version?

Golubev

@jsulm Also with Qt 6.9.0
( image )

as u see its a win 11 problem becase i open Qt project example "declarative-camera". But laptop sad me that camera is started.