A camera problem.

[JonB]

@jenya7
OK, but why not try the example from the docs, in a standalone test program? Not going to say it again.....

[jenya7]

@JonB said in A camera problem.:

@jenya7
OK, but why not try the example from the docs, in a standalone test program? Not going to say it again.....

It runs on Windows machine. Have to arrange some camera....

[JonB]

@jenya7
What runs on Windows machine? It's just sample code, does it not run on whatever platform you are on? You may know better than I, I'll keep quiet now.

[jenya7]

@jsulm said in A camera problem.:

@jenya7 said in A camera problem.:

I see the Camera object is created before MainWindow::MainWindow(QWidget *parent) constructor.

Where do you see it and where do you create camera object? Can you please post relevant code?

I put a break point in the MainWindow constructor and Camera constructor and see which hits the first.
This way it works without errors

QCameraViewfinder *v_finder;

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    v_finder = new QCameraViewfinder(this);
    v_finder->show();

    ui->setupUi(this);
    ui->textEditTerminalTx->installEventFilter(this);
}

void Camera::setCamera(const QCameraInfo &cameraInfo)
{
       //........................

     m_camera->setViewfinder(v_finder);

      //............................
}

Is it OK?

[JonB]

@jenya7 said in A camera problem.:

I put a break point in the MainWindow constructor and Camera constructor and see which hits the first.

And what was the result?!

I see the Camera object is created before MainWindow::MainWindow(QWidget *parent) constructor.

At the time your Camera::setCamera() is called, has v_finder = new QCameraViewfinder(this); been executed yet? If not then v_finder in m_camera->setViewfinder(v_finder) will be nullptr....

[jenya7]

@JonB said in A camera problem.:

@jenya7 said in A camera problem.:

I put a break point in the MainWindow constructor and Camera constructor and see which hits the first.

And what was the result?!

I see the Camera object is created before MainWindow::MainWindow(QWidget *parent) constructor.

At the time your Camera::setCamera() is called, has v_finder = new QCameraViewfinder(this); been executed yet? If not then v_finder in m_camera->setViewfinder(v_finder) will be nullptr....

m_camera->setViewfinder(v_finder) is executed first

[JonB]

@jenya7
Then obviously it is not the right place to put m_camera->setViewfinder(v_finder);.... You cannot execute that line until both m_camera & v_finder have been initialized, so move it somewhere suitable.

[jenya7]

@JonB said in A camera problem.:

@jenya7
Then obviously it is not the right place to put m_camera->setViewfinder(v_finder);.... You cannot execute that line until both m_camera & v_finder have been initialized, so move it somewhere suitable.

I'll try

[mchinand]

It seems your code is largely based on the Camera Example; is that correct? Does that example work for you unmodified?

[jenya7]

@mchinand said in A camera problem.:

It seems your code is largely based on the Camera Example; is that correct? Does that example work for you unmodified?

It's a widget based example. I removed all widget related stuff cause I don't have all these controls for camera operating in my app. I control the camera with commands I type in a terminal.

[jsulm]

@jenya7 Come on, the question is whether this example works with your camera or not! Can't you simply try that?

[jenya7]

@jsulm said in A camera problem.:

@jenya7 Come on, the question is whether this example works with your camera or not! Can't you simply try that?

I'll try tomorrow. I have to get a camera.

well...in the original example I press on Capture Photo and it stays inactive forever.

[jenya7]

How can I pass a default camera instance to use it later?
In camera.h

class Camera : public QMainWindow
{
    Q_OBJECT

    public:
    Camera();
    void Camera::setCamera(const QCameraInfo &cameraInfo);

    const QCameraInfo* default_camera;   
}

in camera.cpp in a constructor

if (cameraInfo == QCameraInfo::defaultCamera())
{
       default_camera = new QCameraInfo(cameraInfo );
        videoDeviceAction->setChecked(true);
}

in main.cpp

g_camera.SetCamera(g_camera.default_camera );

I get
error: reference to type 'const QCameraInfo' could not bind to an lvalue of type 'const QCameraInfo *'

[J.Hilk]

@jenya7 said in A camera problem.:

I'll try tomorrow. I have to get a camera.

wait!

how do you expect the state to change to a ready for capture == true, when you have no camera connected that could be used ?

[jenya7]

@J-Hilk said in A camera problem.:

@jenya7 said in A camera problem.:

I'll try tomorrow. I have to get a camera.

wait!

how do you expect the state to change to a ready for capture == true, when you have no camera connected that could be used ?

It's connected. The constructor detects it - "dev/video0".

I just wonted to try the original example on Windows. my app is running on Linux.

[jenya7]

@JonB said in A camera problem.:

@jenya7
Then obviously it is not the right place to put m_camera->setViewfinder(v_finder);.... You cannot execute that line until both m_camera & v_finder have been initialized, so move it somewhere suitable.

I resolved the issue. Now I get

Ready for capture: true

But on takeImage

QWidget::paintEngine: Should no longer be called
CameraBin warning: "Resource busy or not available."