Using UDOO camera with OpenCV's VideoCapture class

Hello everyone,

I tried (since last week) to use VideoCapture class of OpenCV (version 2.4.8) in order to read the stream of the UDOO Camera, with no success.

I'm using UDOObuntu, last version.

I know there is a trick with the gstream loopback, but I do'nt understand the point.

So, my question: How to read from UDOO camera with VideoCapture?

For information, I tried my code with an USB camera with no problems.

Code with USB camera (working properly) set on /dev/video3

Code:

 Mat frame;
VideoCapture capture(3);
if(!capture)
  return -1;
capture >> frame;
cv::namedWindow("test");
imshow("test", frame);

I tried to replace capture(3) by capture(0) or even capture(7) but here are the errors:

for capture(0), I get:

and for capture(7):

I also tried a lot of other things by despair,like using gstreamer with appsink directly in the VideoCapture constructor (I followed this answer:http://stackoverflow.com/a/23795492 ):

Code:

VideoCapture capture("mfw_v4lsrc ! ffmpegcolorspace ! video/x-raw-rgb ! appsink"); 

Or using a named pipe as suggested here: http://stackoverflow.com/a/7084081 (option3)

What do I do wrong ?

I know it may be possible to do it using other class instead of VideoCapture, but it's not the point.

Thanks for your help

 

Hi,
I have the same problem, i'm trying to find a solution. Gstream is a solution, but it has some problems with arm.

 

Hello,
did you find a solution ?

I am still looking for any way to do it by VideoCapture, even if it includes Gstreamer pipeline..

What do you mean by "some problems with arm" ?

 

Using a loopback device is the only way you can access the camera on /dev/video7. So, just activate the camera driver with UDOO Configuration Tool (it just creates the loopback device on video7 at startup). Then configure your script accordingly...

 

Hello mikelangeloz,

I already enabled the camera video driver with Udoo Configuration Tool.
Even with the loopback device, I get the following error:

And I'm still incapable of doing anything with the VideoCapture class... :cry:

 

Hi, sorry i'm late!
I tolked with udoo team! and there is a solution!
In the new udoo realise, there is a udoo configuration tool, starts it, and select enable UDOO Camera Module.
Now you can use udoo camera with openCV!

try and tell my!

 

Hello
I'm new with UDOO and I'm trying to acquire frames from the UDOO camera from python programs with opencv and I’m facing this problem. I already use the ‘udoo configuration tool’ to activate the UDOO camera and it is working with ‘gst-launch-0.10 mfw_v4lsrc ! …’ commands.
Has anyone already solved this issue?
Thank you for feedbacks.
pmjorge

 

I solved the problem only writing in the instruction "cap=cv2.VideoCapture()" the number 7 like this cap=cv2.VideoCapture(7)