Qt5 directshow plugin (dsengine.dll) is not built under Windows7 - qt

I’ve tried to build the directshow multimedia plugin in Qt5 under Windows7, however, there is a problem that qedit.h is not found, as this file was removed from WindowsSDK 7.1 (which is the one I am required to use to build Qt5).
So I tried to follow this post here.
Just adding this qedit.h (from what I see it just needs the IID_ISampleGrabber and CLSID_SampleGrabber and that’s it) and recompiling. It linked alright, but when I run my application, if I try to play video it just doesn’t do a damn thing, and if I try to access the camera it just quits the application right away. Since I have no idea about the inner workings of DS, I don’t know how legitimate this fix is.
How do I fix this?
Thanks.

Related

Qt6 integration of 3dconnexion spacemouse devices

hope this finds you well.
I have been wondering if there are any updates regarding qt integration of the spacemouse sdk.
I found this old post https://forum.3dconnexion.com/viewtopic.php?f=19&t=4968 but all the source code files are not present anymore and I don't think I'm skilled enough to rewrite it given the information present in the forum (here's the updated link to the post https://www.codegardening.com/post/2011/2011-02-05-using-the-3dconnexion-mouse-with-a-qt-application/) and honestly it looks strange to me that Qt has not yet made any integration packages for 3d connexion devices.
I am using Visual Studio 16 on a Windows machine in a Qt6 VTK9.2 OpenCV project
I have tried the basic windows way using window handlers but I can't make it work (no input read) as soon as I pass the handler to the qMainWindow as HWND(mainWindow.winId()), while it works fine if I create a dedicated window to read the data.
Could you please give me some suggestions or point me to some resources?

The plugin '[path]/APlugin.dll' uses incompatible Qt library. (4.8.2) [debug]

I am trying to compile a Qt Library Project to use its DLL as a plugin of my Main Application.
I've come across this particular error and I cannot seem to get past it, no matter what I try.
I believe cluttering the question with code tags is pointless when I can just provide you with the "working issue" (for lack of better wording).
This is a link to both projects. The main application AND the plugin I am currently testing on.
(please remember to modify the path in the Application project of the dll. I am using absolute path, which will most likely never be the same one you will use. I used absolute paths to make sure the problem was unrelated to finding the file itself)
So far I've checked:
My Qt version is, indeed, 4.8.2. Built with VS2010 Command Prompt.
As far as I understood the documentation, my code (particularly the APlugin project) follows the documentation instructions word by word. There's some space for human error, but I believe I got it right. as specified here(The Lower-Level API: Extending Qt Applications)
I am able to generate other QPluginLoader::errorString() errors (for example, using an invalid path to the .dll file will return a "file not found" error). Thus diminishing the margin of error in its use.
As of today, Google results are, at best, cryptic and/or do not apply to my current context of development (I am on VS2010, Win7 N Ultimate, Qt 4.8.2)
I believe it's better that I provided projects where the issue is reproducible, instead of just cluttering the question with code, but if you think I still should copy-paste my code, let me know and I will provide it explicitely in the question.
The only thing I am able to provide so far is that, albet I don't use a .pro file, I shouldn't need it, because my application will be windows exclusive, and the vcproj file already contains that data.

Error building QtCore

I am trying to build QtCore.lib and I get this weird error.
PRJ0019: A tool returned an error code from "MOC kernel\qtimer.cpp"
I am able to build qtmain.lib but not able tp go any further.
moc.exe is available in bin folder and the path is added to my PATH.
kernel\qtimer.cpp file is also present in corelib folder.
Any help in this regard will be appreciated. I am building with Qt-4.5.2 source.
In Qt 4.5.2 moc.exe has some issues. An email I sent to Qt Support mentions it moc'ing files that were not modified. It could have further issues, which could be related to what you are experiencing.
Sorry I can't recall the exact details. To make things worse the link Qt Support had sent me at the time is broken.
They had suggested using 4.5.3. I think we ended up staying on 4.5.1, which we are still using today, although the move to 4.7.x. is occurring as I write this. :)

Qt: QWebview not displaying jpg, gif, png images on another machines

Today I came across a very strange error with QWebView which I cannot resolve myself.
I included a QWebView widget in my application. When I set a URL or a piece of HTML code to display (with QWebView::setUrl() or QWebView::setHtml()), it works very well on my machine. It also works on all machines that have Qt installed, but not on those without it. I compiled a release build and included all necessary libraries as shared (QtWebKit4.dll, QtNetwork4.dll etc.), so I guess my error lies in that I forgot to include some libraries.
If anybody has already had such an error, I would be very grateful for help!
You might need to include the relevant Qt image processing plugin libraries, which are located in qt/plugins/imageformats (and maybe also qt/plugins/iconengines ). I haven't deployed any webkit apps, so I'm not certain about this.
See my answer to this question: Qt dll deployment on windows

Could not open the editor: Assertion failed:

when i open .mxml flex file in eclipse it gives error
Could not open the editor: Assertion failed:
Does any one know about it
First of all you can give which operating System and version, IDE version, Flex plugin version, detail of error message. You can try ;
Check eclipse and flex plugin version compatibility if you use flex plugin. (If you use Linux operating system flex plugin compatible with eclipse 3.3 ide if not You can try to install flex plugin on eclipse 3.3 if you use 3.4 or 3.5 and so on)
You can download full package of flex ide instead of flex plugin on eclipse
I think its better to stop searching when you are in Flash and Linux. Here in this link its very much transparent. I tried all the fix provided out there, nothing did really worked what new comers are looking for.
Details: http://labs.adobe.com/technologies/flex/flexbuilder_linux/releasenotes.html#sysreq
Note: GUI will never work, which we are thinking and Autocomplete etc will also not work. So Flash and Linux is actually useless and time lose. The best thing is keep reporting Adobe for this. Because they are counting our Linux Vote.
Try changing your current workspace to another one, it helped in my case.
If you have disabled asking for workspace at startup you can change it here:
Window > Preferences > General > Startup and Shutdown
I just got the same error, after moving my project to a new computer. Turns out the build paths needed to be changed in the new computer. After updating those it seemed to fix the problem.
I struggled with this a couple of hours: my own "solution" to this was that I had Eclipse Galilieo / Weblogic 10.3.2 / Windows 7 set up correctly, but was accidently opening an old Eclipse Helios install pointed to the same projects. In other words yes, its likely a slight path difference or a new name for an updated resource along one of your paths. "assertion failed" is such a generic exception that you could get with so many different softwares, that I thought this input wouldnt hurt...

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