opencv app with multiple windows - only window with focus gets refreshed constantly - visual-c++

I'm working on an C++ app which uses opencv for some data manipulation and visualization. I'm using three to four cvShowImage() statements to visualize the data. I've recently noticed, that only the window which has focus, will be updated constantly after each cvShowImage() call. All the other windows only get updated infrequently. Is there a way to make sure that all opencv windows get refreshed and updated?

If you don't already, I would suggest issuing a cvWaitKey(30) after each cvShowImage() and not only once after the last one. Or you could try displaying all the images in one window.

Related

Excel VBA Userform keeps resizing

When I'm using my external monitor and close an executing userform, it returns to the Visual Basic Windows smaller than designed, as shown below.
What happens is, if I execute it again without reajusting, it goes to the user with this reduced proportion.
It behaves like this only with an external monitor (I've tried different ones, same result).
Any ideas?
This bug started happening to me when I started using two screens, I don't know if it's related to using two screens

How can one greate grid/tile view of selected parts of windows on xfce/linux

I have a few windows on my linux machine using the xfce4 desktop enviorment.
I wish to have a grid-like view where i can see only the part of each window im intrested in.
An example for the general vision:
see a script running without the window borders on terminal across the header
see work status of F#H client out of the advenced client view in the middle left
see only the turrents status list of qBittorrent at middle right
have another terminal at footer (again without header/borders)
My best way to describe it shortly is to generate a view from selective parts of windows.
Added a picture for illustration
Is there any way of doing such thing in a practical way? Am i missing out on a great software?
There are several tiling helpers for Xfce.
Perhaps try xpytile , which is a tiling add-on for Xfce. It offers
automatic tiling, manual tiling and can simulaneously resize side-by-side windows (like AeroSnap for MS-Windows).

How to launch new window below current window using xulrunner

I have situation that I'm calling mplayer every x minutes from xulrunner application and it always gets focus and comes on top, in front of other windows. But I need it to be behind xulrunner which has transparent box in which video should be visible.
Is there some way to force new process (mplayer) to be behind oldier process (xulrunner) and not to get autofocus on it?
Is it a Linux window manager level or there's some property in xulrunner or mplayer? (I'm using Fedora 18 with Openbox)
A solution can be achieved using devilspie. This tool allows you to customize many properties of application's windows including their focus, decoration, placement, and geometry. There is a handy frontend for it called gdevilspie, though there are no rpms available so it must be installed from source.
You can set devilsiie to match on all mplayer windows and set their action to "below" which will place them below all normal windows. Unfortunately this will apply to all invocations of mplayer, so this solution may be annoying if you use mplayer under other circumstances.

No keyboard input in Unity3D game builds

I'm using Unity3D and I'm having issues with the keyboard when I 'build' the project.
When I run the game within the Unity Editor, the input works fine. However, when I build the project and test it, I have no directional input whatsoever. The mouse works fine, the game registers keystrokes (the Esc key works), but the player won't move.
I'm using Input.GetAxisRaw("Vertical") and Input.GetAxisRaw("Horizontal")
I researched the issue on the web, but I'm still stucked. The only solution I found (in various links) mentions a problem with DirectInput and states that you should remove the key "Input" from [HKEY_CURRENT_USER\Software\Unity\Player], in the Windows registry, but that doesn't seem to work for me.
Has anybody else fought this problem? Any working solutions? Am I doing the registry trick wrong?
You should check out Input Manager in Edit->Project Settings-> Input. Have you tried using GetAxis instead of GetAxisRaw? I also suggest using, eg: Input.GetKey(KeyCode.A) and etc.
I've figured out what was troubling me.
Input.GetAxisRaw("Vertical") and Input.GetAxisRaw("Horizontal") were fine the whole time. Somehow, there was some code in the script that in the Editor worked just fine, but when running as standalone gave me a calculation equal to 0 (it depends on the Delta Time, so I assume that the Delta Time when running compiled is much smaller than when running in the Unity Editor) and thus the character didn't move at all.

Screen capture doesn't work on MFC application in Vista

We've got some in-house applications built in MFC, with OpenGL drawing routines. They all use the same code to draw on the screen and either print the screen or save it to a JPEG file. Everything's been working fine in Windows XP, and I need to find a way to make them work on Vista.
In three of our applications, everything works. In the remaining one, I can get the window border, title bar, menus, and task bar, but the interior never shows up. As I said, these applications use the exact same code to write to the screen and capture the window image, and the only difference I see that looks like it might be relevant is that the problem application uses the MFC multiple document interface, while the ones that work use the single document interface.
Either the answer isn't on the net, or I'm worse at Googling than I thought. I asked on the MSDN forums, and the only practical suggestion I got was to use GDI+ rather than GDI, and that did nothing different. I have tried different things with every part of the code that captures and prints or save, given a pointer to the window, so apparently it's a matter of the window itself. I haven't rebuilt the offending application using SDI yet, and I really don't have any other ideas.
Has anybody seen anything like this?
What I've got is four applications. They use a lot of common code, and share the actual .h and .cpp files, so I know the drawing and screen capture code is identical.
There is a WindowtoDIB() routine that takes a *pWnd, and a source rectangle and destination size. It looks like very slightly adapted Microsoft code, and I've found other functions in this file on the Microsoft website. Of my four applications, three handle this just fine, but one doesn't. The most obvious difference is that the problem one is MDI.
It looks to me like the *pWnd is the problem. I'm not a MFC guru by a long shot, and it seems to me that the problem may be that we've got one window setup in the SDIs, and more than one in the MDI. I may be passing the wrong *pWnd to the function.
In the meantime, it has started working properly on the 64-bit Vista test machine, although it still doesn't work on the 32-bit Vista machine. I have no idea why. I haven't changed anything since the last tests, and I didn't think anybody else had. (On the 32-bit version, the Print Screen key works as expected, but it does not save the screen as a JPEG.)
Your question title mentions screen capture but your actual question doesn't. Please elaborate more clearly. Is the problem that you can do screen capture of three of your applications, but not the fourth one? You can use different screen capture software that can capture OpenGL/DirectX windows. Those surfaces are handled directly by the Window Manager and won't show up with a simple 'PrtScn'.
Switching to GDI+ won't solve it, nor will switching to SDI.
If it's the content of the CView that you want, then yes, that should be right one. If it's the content of the whole screen (at least the content, without the toolbar(s) and status bar), then you should pass it the CMainFrame (that's the default name which may have been changed, the one that is derived from CMDIFrameWnd).
Can you post the code of WindowToDIB()? I've just tried it and It Works For Me (TM), but without OpenGL code in the view. Try passing the following windows to your WindowToDIB() function:
CMainFrame* mainfrm = static_cast<CMainFrame*>(::AfxGetMainWnd());
- mainfrm
- mainfrm->MDIGetActive()
- mainfrm->MDIGetActive()->GetActiveView()
and see what you get.
The contents of each window are directX surfaces and are only assembled by the window manager in the graphics card. You'd not be able to capture this unless you switch off the new interface (DWM) or code specifically for screen capture from the DWM.
Wikipedia has a good description of the Desktop Window Manager (DWM)
Sorry, I still don't understand. You're trying to get the Print Screen key to work on all four applications? Or you're trying to get the WindowtoDIB() function to work, which takes a 'screenshot' (from within your own application) of the application itself, so that it can be saved as an image file?
Also, what do you mean with 'he Print Screen key works as expected, but it does not save the screen as a JPEG.'? Print Screen only copies to the clipboard, what happens when you paste in Paint?
If your WindowtoDIB() function only 'captures' the window you pass to it, then yes, your MDI child windows are not going to show up.
We eventually solved this by creating a different OpenGL context, and drawing everything to that. We gave up on the screen capture.

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