Using QCamera with multiple cameras

[sulabh]

Hello, I am trying to show the one camera output on two QLabel widget. However I am not able to do so. I encounter following error.

Graph failed to connect filters -2147024809

However I can see it on one screen not on another. If this is a wrong approach or is it not possible at all?

cM = new QCamera(this);
cM2 = new QCamera(this);
cV = new QCameraViewfinder(this);
cV2 = new QCameraViewfinder(this);
mMenu = new QMenu("Options",this);
cA = new QAction("one camera", this);
cA2 = new QAction("both camera", this);
mMenu->addActions({cA, cA2});
ui->pushButton->setMenu(mMenu);
cM->setViewfinder(cV);
cM2->setViewfinder(cV2);
cBox1 = new QVBoxLayout();
cBox2 = new QVBoxLayout();
cBox1->addWidget(cV);
cBox2->addWidget(cV2);
ui->label->setLayout(cBox1);
ui->label_2->setLayout(cBox2);
connect(cA, &QAction::triggered, [&](){

   
    cM->start();

    cM2->start();
});

[Chris Hennes]

This post is deleted!

[SGaist]

Hi and welcome to devnet,

You should setup both your cameras explicitly using e.g. QCameraInfo.

[sulabh]

@SGaist Hi Thank you for your reply. Main issue is regarding the device, I have one device which has two ports. This means i can only activate one at a time. In case, I need to change to another camera i always have to switch the channel. My idea was to display both at a time by switching channel very fast. So it looks like they are both working.

Anyway is it possible to display one live stream on two different screens(same widget type)? However i could not find what this error means.

Thank you for your reply.

[SGaist]

The error message indicates that the direct show backend failed the setup.

What kind of camera is it ?

[sulabh]

@SGaist Hey it finally worked... Thanks for the help

[SGaist]

You're welcome !

What did you do to make it work ?