Kinect v1 integrates with qt - c++

I have been working with Qt and Kinect v1 for couple of weeks. I don't know how to create a screen inside a Qt GUI and show stream video captured by Kinect.
I have searched for a in-depth tutorial in the Internet but it seems like nothing related directly to my problem.
I prefer programming in C++, using Qt 5.6. I know how to use some basic Qt feature but have never experienced with OpenGL in qt before. I can also run Kinect using Developer Toolkit browser and it works perfectly. Then I saw a tutorial using kinect and C++ at the link: https://homes.cs.washington.edu/~edzhang/tutorials/kinect/kinect2.html.
I followed the instructions and I can create a new windows show the stream video captured by Kinect sensor but when I using the same code in the Qt project, it just only show a black video. I don't know how to resolve the problem at all. The code is too long because I write it in the project created last week.

Related

Recording desktop using Qt multimedia

I'm trying to record microphones, cameras and monitors using Qt's multimedia module. But I couldn't find anything about screen recording in documentation. So it seemed I'd to do it by myself.
I've searched about that, found that answer:
How to display desktop in windows form using Qt?
Seems I've to use FFMPEG to merge these taken screenshots into mp4 file, also it doesn't seem an efficient way. I want to show real time recording output with QVideoWidget. I was going to use QMediaCaptureSession, QMediaRecorder. But they only work with camera. Is there any way to record desktop screen with Qt's multimedia module?
P.S: Please correct me, if my question is wrong

How can I combine Kinect data with Qt5?

I'm currently trying to create a GUI that will display Kinect data as well as a couple control features (buttons, etc.) and a graph. The control features and the graph is simple enough however I'm a bit stuck on how to continue on with the Kinect.
I've looked at numerous examples for MSVS and Kinect Studio but I can't quite figure out how to import the Kinect data to my Qt script. Also, I need it so that the Qt data can be recorded then replayed when a button is pressed.
How should I go about this? My hope is some how I can extract the Kinect data in its raw (x,y,z) format then reconstruct the data using openGL? I've seen references of OpenNI as well as OpenCV but I'm unfamiliar with either. I'm pretty familar with Qt but have virtually no experience with Kinect development.
I'm currently using Qt5 Creator, MSVS2015, and Kinect SDK2.

OpenGL - Display video a stream of the desktop on Windows

So I am trying to figure out how get a video feed (or screenshot feed if I must) of the Desktop using OpenGL in Windows and display that in a 3D environment. I plan to integrate this with ARToolkit to make essentially a virtual screen. The only issue is that I have tried manually getting the pixels in OpenGl, but I have been unable to properly display them in a 3D environment?
I apologize in advance that I do not have minimum runnable code, but due to all the dependencies and whatnot trying to get an ARToolkit code running would be far from minimal. How would I capture the desktop on Windows and display it in ARToolkit?
BONUS: If you can grab each desktop from the 'virtual' desktops in Windows 10, that would be an excellent bonus!
Alternative: If you know another AR library that renders differently, or allows me to achieve the same effect, I would be grateful.
There are 2 different problems here:
a) Make an augmentation that plays video
b) Stream the desktop to somewhere else
For playing video on an augmentation you basically need to have a texture that gets updated on each frame. I recall that ARToolkit for Unity has an example that plays video.However.
Streaming the desktop to the other device is a problem of its own. There are tools that do screen recording, but you probably don't want that.
It sounds to me that what you want to do it to make a VLC viewer and put that into an augmentation. If I am correct, I suggest you to start by looking at existing open source VLC viewers.

Qt QML and 3d: are these two frameworks the same?

Anyone who has experimented with Qt QML and 3D OpenGL, I am interested in 2 frameworks I've read about, but it is not clear to me if in fact they are the same framework. The most interesting of the two is outlined in this Qt Developer Days 2013 video presentation by Krzysztof Krzewniak:
http://www.youtube.com/watch?v=29wCpA0DBZI
While very interesting, unfortunately I cannot find anywhere else online some source code for this, or even the name of the framework discussed.
There is QtQuick3d:
http://doc.qt.digia.com/qt-quick3d-snapshot/
However, I cannot tell if in fact this is describing the same framework from Dev Days or if they are separate (and apparently somewhat similar) frameworks? My initial look at the API in comparison to the video suggests they are different, which seems rather redundant to have 2 significant projects in the Qt community attempting to do the same thing.
Can anyone with some knowledge in this area of QML provide some pointers here?
Right, so let us start with some history behind...
Qt was initially a 2D framework for rendering computer graphics UI for simple desktop applications.
Qt3D was developed earlier than qml became mature as an extension to the 2D world provided by the QtGui module, or even QtOpenGL.
It was a 3D Qt api for rendering 3D content on the screen. It had different aspects to deal with 3D objects, build them, put them on the screen, compute intersection, and so on.
The idea was to bring easy to create application concept into Qt rather than always going through QtOpenGL or lower-level API for creating games, simulators, cad applications, and so on.
Right, when QML came out and kept maturing, the Qt3D contributors in Brisbane thought that it would be nice to put a QML API on top of the existing Qt3D C++ API for easy use in QML application. That is how we come to QtQuick3D.
When Nokia decided to shut the Brisbane office done, the Qt3D module pretty much became unmaintained and abandoned only getting a few bugfixes from the community every now and then.
There is some work in progress by KDAB to re-architecture and re-design the module, but it is not mature yet, and it can be found in a separate branch.
The video you are referring to is not dealing with the unmaintained Qt3D module. Rather, it tries to build 3D based on the new scene graph introduced in Qt. Since, there is no Qt3D module working nicely with the new SG in Qt 5, people become pragmatic and move on. That is what you see in the video.
Now, as you can see this is not quite a duplication, but... In the future, the new Qt3D architecture might be acting better with the new scene graph. In fact, KDAB has put a lot of effort into bringing the OpenGL support into QtGui up to real world.
That was the foundation for the Qt3D module which will probably be used in the future (hopefully) by 3D applications written based on Qt, but in the meantime... the video shows how to build hardware accelerated 3D UI based on what we have today.
These two 3d libraries are not the same, you are correct.
There is plenty of reference information you've already linked to online regarding Qt3d 1.0 and QtQuick 3d which are similar and related.
The OpenGL work in the video presentation is something much newer. It is directly laid on top of the QSceneGraph and QQuickWindow functionality.
My recommendation is to not use the approach in this video or the Qt3d/QtQuick3d library. Instead, wait for the KDAB to finish Qt3d 2.0 (which may already be out, you should check). Qt3d 2.0 is a full library for QML that will let you do what is demonstrated in this video.
(http://qt-project.org/wiki/Qt3D-wip-newapi-Overview, http://prezi.com/u-ewejoqxqj2/qt3d-20/)
There are quite a lot of outdated info floating around wikis, and finding useful info and a non-obsolete repository was a pain. So here's what I learned a few months back:
The correct and, as far as I know, the only currently valid git repo is this:
git://gitorious.org/qt/qt3d.git
The "There is some work in progress by KDAB...not mature yet...found in a separate branch." paragraph of Laszlo Papp's answer seems to refer to wip/newapi branch, while master branch seems to be maintained in compilable state (meaning, I have been able to compile it the few times I've tried, YMMV). Master branch should be fine for playing around with Qt3D, but looks like API is going to change.
I played with it a few months ago on Windows 8.0, the MinGW toolchain that is installed with SDK, and using native full OpenGL drivers (which I had to fetch from ATI web site for my card, default Windows drivers are not enough). And looks like it has not broken to bit rot, an example still built and I have a moon rotating on this screen.
It has README file, which will tell you how to build it, starting with building Qt5. Here another good link for that, since the qt3d README is not very comprehensive. And if you're on Windows, just skip Webkit and its deps, unless you really need it, because those extra deps can be a bit of hassle.

Can't get supported resolutions of the camera for image capturing using QCamera in Qt 5.0.2 (Linux)

I am trying to write a simple program for taking photos from the webcam using Qt.
There is an example project in the Qt Creator, where QCamera is used to take photos and record video. But it is not working the right way. I can't get supported resolutions of the camera using method QCameraImageCapture::supportedResolutions(). A null QList object is returned, and camera is always capturing images with 640x480 resolutions.
OS is Ubuntu 11.04. Same problem occurs on Windows XP.
Can anyone help me?
I have answered nearly the same question.
https://stackoverflow.com/a/21140214/2452081
In short:
Portable solution can be gstreamer, but if Windows DirectShow solution is enough for you download my code from here