RVCamera doesn't show video if VideoDeviceIndex is set and SetCamVideoMode(0) is called before PlayVideoStream

[ya_vanka]

Found an issue with RVCamera.

In my project I should set RVCamera.VideoDeviceIndex and call RVCamera.SetCamVideoMode() just before RVCamera.PlayVideoStream.

The issue is that if I pass 0 to RVCamera.SetCamVideoMode() then video is not shown (and RVCameraGetImage() is not being called). If I pass any other value (> 0) then everything is ok.
This issue appeared in version 7. In version 6 there was no such a problem.

You can reproduce the issue by adding two lines in procedure TfrmMain.btnOnClick of the demo project "WebCamera":

Code: Select all

procedure TfrmMain.btnOnClick(Sender: TObject);
begin
  RVCamera1.VideoDeviceIndex := cmbCamera.ItemIndex;
  RVCamera1.SetCamVideoMode(cmbVideoResolution.ItemIndex);

  RVCamera1.PlayVideoStream;
end;

Could you please fix the issue.

[ya_vanka]

Have you reproduced the issue?

[Sergey Tkachenko]

Sorry, not yet. I'll check it tomorrow.

[Sergey Tkachenko]

It looks like the problem occurs when you call SetCamVideoMode with the parameter equal to GetCamVideoModeIndex.
It can be reproduced in the original webcam demo by choosing a video mode in the combo box that is already selected.
While it can easily be fixed by checking for this case, I am still trying to understand why it happens...

[Sergey Tkachenko]

Fixed in RVMedia 7.5

[ya_vanka]

Great!
Going to upgrade and test.