Implementing Open CV in QTCreator on Raspberry Pi - opencv

I try to record a video with my USB Webcam in a QT GUI Application on my Raspberry Pi.
All tutoriuals I can find focus on cross-compiling. I want to program and build this directly on the Pi. I've succesfully installed QT Creator and build GUI Applications, they're working.
Questions:
Is it possible to implement OpenCV into the RaspberryPi QT Creator? If yes, how?
Is this the correct approach to solve the problem?
Is there a better way to record videos with a QT GUI Application beside Open CV?
Thank you very much!

Related

Sony Spresense Arduino audio recording with digital microphones

The examples and documentation for the Spresense have a lot of very clear information, yet I think there's something missing for using digital mics with the Arduino IDE. Modifications to the extension board for using digital mics are very clearly documented with nice pictures. The Arduino example projects are great, showing you to record, encode, etc. And I've also understood you must tell the recorder to use the digital microphones with the following:
theAudio->setRecorderMode(AS_SETRECDR_STS_INPUTDEVICE_MIC_D);
There are also nice details in the audio documentation explaining that CXD56_AUDIO_MIC_CHANNEL_SEL must be changed from the default value of 0xFFFF4321, which is for analog microphones, to values for digital microphones. I've been able to follow the instructions for rebuilding the Nuttx kernel and spresense SDK with a new value of 0xCBA98765 which should enable eight digital mics. The last piece that is not clear is what nuttx/sdk binary files now need to be copied over to the Arduino environment. I have a Windows PC for use with the Arduino IDE and I have a Linux PC for building Nuttx and those examples. Can you please list which files on the Linux machine that I need to copy over to the Windows PC for the Arduino IDE to use the SDK that enables the digital mics? Sorry if this is documented somewhere and I overlooked it!
The instructions provided by Sony to record using the digital mic work fine! It was a hardware problem with my microphones. I was able to use the nuttx example named audio_recorder. I haven't tried with Arduino and the process of copying files from a nuttx build to the arduino build folders is still not very clear, but that's a separate issue.

Point Grey Bumblebee2 firewire 1394 with Nvidia Jetson TK1 board

I have successfully interfaced Point Grey Bumblebee2 firewire1394 camera with Nvida Jetson TK1 board and I get the video using Coriander and video for Linux loop back device is working as well. But when I tried to access camera using OpenCV and Coriander at the same time, I have conflicts. And when I tried to access the video from camera by closing the Coriander then I can get the video but in that case I am not able to change the mode and format of the video. Anyone can help me to resolve this problem. Can I change the video mode of the camera from OpenCV.
You will have to install the flycapture sdk for ARM if you want to do it manually (by code). The flycap UI software i dont believe works on ARM, let alone ubuntu 14.04, just ubuntu 12.04 x86. If you have access, what I usually do is plug it into my windows machine and use the Flycap software to change the configurations on the camera.
I found this question completely randomly, but coincidentally I am trying to interface the bumblebee2 with the jetson right now as well. Would you care to share as to what firewire mini-PCIe you used and how you went about any configurations (stock or grinch kernel, which L4T version) ?
Also, although not fully complete, you can view a code example as to how to interface with the camera using the flycaputre sdk here: https://github.com/ros-drivers/pointgrey_camera_driver. It is a ROS driver, but you can just reference the PointGreyCamera.cpp file for examples if your not using ROS.
Hope this helps
This is not well advertised, but PtGrey do not support firewire on ARM (page 4):
Before installing FlyCapture, you must have the following prerequisites:... A Point Grey USB 3.0 camera, (Blackfly, Grasshopper3, or Flea3)
Other Point Grey imaging cameras (FireWire, GigE, or CameraLink) are NOT supported
However as you have seen it is possible to use the camera (e.g. in Coriander) using standard firewire tools.
libdc1394 or the videography library should do what you need.

VideoCapture.open(0) won't recognize pi cam

I have been working with my Raspberry Pi 2B for a while now. Testing the Pi cam using raspistill works great but trying to use OpenCV functions such as VideoCapture.open(); won't work. trying the same command with a USB camera works just fine. I tried different indexes as inputs but nothing works for the pi cam. What am I missing here?
sudo modprobe bcm2835-v4l2
will "enable" the camera for opencv automatically.
make sure you have the camera enabled from the raspberry config, either gui or raspi-config. the above loads the necessary drivers to handle everything automatically, i.e. loads the appropriate interfaces (v4l2 drivers) for the raspberry camera.
works out of the box on raspbian jessie. other releases might include the drivers by default, but the link below contains info on compiling the drivers in your worst case. so you should be able to get this to work with pidora as well.
more info: https://www.raspberrypi.org/forums/viewtopic.php?f=43&t=62364
I assume your question is about the C++ API, not the python one? As far as I understand the raspberry pi camera is not a usb camera and as such should be approached differently. For python there is is picamera package which works like a charm (with opencv). I never used the C++ interface but a quick google leads to this

Jmyron and Windows 8

I am running into hardware issues that perhaps someone here knows a workaround. I am using a PC and windows.
For several years I have been making interactive installations using video tracking: the Jmyron library in Processing, which has functioned marvelously for me. I use this set up: cctv type microcameras to a multiplexer, the I digitize this signal via a firewire cable to a pci card. Then Processing reads these quads (sometimes more) as a single window, and it has always worked (from windows xp all the way to 7). Then comes windows 8: Processing seems to prefer the built-in webcam to the firewire bus. On previous version of windows, the firewire bus would naturally override the webcam, provided I had first opened a video capture in Windows Maker, and then shut it down before running the Processing sketch. In Windows 7, which had no native video capture software, I used this great open source video editor called Capture Flux. The webcam never interfered. With Windows 8, no matter what I try, Processing defaults to the webcam, which for my purposes is useless. I have an exhibition coming up real soon, and there is no way I am going to have the time to rewrite all that code for Open CV or other newer libraries.
I am curious if anyone has had similar problems, found a work around? Is there a way of disabling the webcam in Windows 8 (temporarily of course, because I need it to be operational for other applications), or some other solution?
Thank you!
Try this:
type "windows icon+x" choose device manager (or use run/command line: "mmc devmgmt.msc")
look for imaganing devices, find your integrated webcamera
right click on it and choose disable - now processing should skip the device.
Repeat the steps to reenable the device.
Other solution would be using commands in processing:
println (Capture.list()); (google it on processing.org) this way you will get all avaliable devices and you can choose the particular one based on its name.
Hope this helps.

OpenCV codes in Code Composer (CCStudio)

I'm using CCStudio v5 to implement a vision system and want to use OpenCV functions in my code, but I don't know it is possible to use OpenCV code in CCStudio or not!
How I can import OpenCV library into my CCStudio project? Is this depends on my hardware?
There is no official release of OpenCV for system without OS. OpenCV library is available for Windows, linux, mac, Android and Ios operating system.
Here
you can find a link which explain the challenges of having OpenCV running on microcontrollers

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