Ubuntu 14.04 + Mint 17.1 - Needs python-opencv package installed

Question

Ubuntu 14.04 + Mint 17.1 - Needs python-opencv package installed

13rac1 opened this issue 9 years ago · comments

The pip cv2 package doesn't contain a working opencv installation for Ubuntu 14.04 + Mint 17.1. Not sure about other OSs.

Installing the apt-get package makes this program run.

sudo apt-get install python-opencv

pyskell · Answer 1 · Tue Oct 13 2015 08:48:40 GMT+0800 (China Standard Time)

Thank you.

Will add this to the README
On Oct 12, 2015 8:46 PM, "Brad Erickson" notifications@github.com wrote:

The pip cv2 package doesn't contain a working opencv installation for
Ubuntu 14.04 + Mint 17.1. Not sure about other OSs.

Installing the apt-get package makes this program run.

sudo apt-get install python-opencv

—
Reply to this email directly or view it on GitHub
#5.

Bradley Erickson · Answer 2 · Tue Oct 13 2015 11:25:01 GMT+0800 (China Standard Time)

I've run into the super common: https://bugs.launchpad.net/ubuntu/+source/cheese/+bug/1295247

I suggest recommending the above package, then if that doesn't work, compiling OpenCV from source: http://docs.opencv.org/doc/tutorials/introduction/linux_install/linux_install.html I was able to get a far more detailed error message from OpenCV 3.0:

$ python slouchy.py 
VIDEOIO ERROR: V4L/V4L2: VIDIOC_S_CROP
"sni-qt/24493" WARN  19:20:08.782 void StatusNotifierItemFactory::connectToSnw() Invalid interface to SNW_SERVICE 
VIDEOIO ERROR: V4L2: Pixel format of incoming image is unsupported by OpenCV
Unable to stop the stream.: Bad file descriptor

Either way, this the same issue I've experienced before with an unsupported pixel format for my webcam. None of the different options for libv4lfix the problem.

David Grant · Answer 3 · Tue Oct 13 2015 17:39:57 GMT+0800 (China Standard Time)

I'm not seeing this in the README. Why did you close it eosrei?

David Grant · Answer 4 · Tue Oct 13 2015 17:44:17 GMT+0800 (China Standard Time)

Also needs opencv-data installed for the /usr/share/opencv/haarcascades/haarcascade_frontalface_default.xml file. Please re-open.

Bradley Erickson · Answer 5 · Tue Oct 13 2015 22:27:26 GMT+0800 (China Standard Time)

I closed because while it makes the program run, it does not make it functional on my system therefore I cannot claim it is a valid solution. My webcam is unsupported by the libraries required by OpenCV, same issue I have with Cheese (at greater than 640x480) and Google Hangouts in Chrome. If everything works for your system, please open a new issue with the full steps to reproduce. I made sure to link the Launchpad bug and show all errors for the significant number of people who will encounter this problem. I cannot say much about the XML file, but I doubt it needs to be outside the repo.

pyskell · Answer 6 · Tue Oct 13 2015 23:02:47 GMT+0800 (China Standard Time)

@eosrei Are you saying your camera works when run at 640x480? If so we may be able to force OpenCV to grab images at a specific resolution. Not sure though, I'd need to look at the docs. 640x480 is a high enough resolution for face detection.

@dgrant For the haarcascade issue I changed the config to use the local repo copy so everyone has a copy even if they're missing opencv-data. Please let me know if this resolves your issue. If not see if there's anything in issue #1. If not please open a new ticket :)

Bradley Erickson · Answer 7 · Tue Oct 13 2015 23:17:03 GMT+0800 (China Standard Time)

Yes, the camera works in applications that allow the resolution to be selected. Cheese works at 640x480, but displays a black screen and throws errors at 1280x720. It's just as described on that Launchpad issue. Slouchy may function if the resolution is reduced.