16
votes
Accepted
Failed to create MMAL component b'vc.ril.camera': Out of memory
This error was resolved when I disconnected and reconnected my camera module.
Somehow my camera module must have been wiggled loose when I was working with it and the Pi was not able to detect the ...
- 422
13
votes
ERROR: Environment '/home/pi/.virtualenvs/cv' does not contain an activate script
I'm running on a raspbian buster with Python 3.7.3. I ran into the same issue, "ERROR...no activation script". I tried @Lombax answer but it didn't work.
However, I noticed that the version of ...
- 131
11
votes
Accepted
How to install OpenCV on Raspberry Pi 3 in Raspbian Jessie?
I was doubtful too about virtualenv, and quite happy to live without it :)
Here are the commands I took from both tutorial you provided, for OpenCV 3.1.0
generic stuff
sudo apt-get update
sudo apt-...
- 1,406
10
votes
ERROR: Environment '/home/pi/.virtualenvs/cv' does not contain an activate script
I am also facing the same error. You must add these lines on ~/.profile
export WORKON_HOME=$HOME/.virtualenvs
export VIRTUALENVWRAPPER_PYTHON=/usr/bin/python3
export VIRTUALENVWRAPPER_VIRTUALENV=/usr/...
- 211
6
votes
Accepted
Is it necessary to release Raspberry Pi Camera before rebooting? If so how do I do it?
There is NO NEED to do anything before a reboot.
If you issue a sudo reboot command Linux will manage an orderly shutdown of the software.
This is, however, a poor way of ensuring a reliable 24/7 ...
- 58.2k
6
votes
How can I use OpenCV with Python 3 on a Raspberry Pi?
It says "Cannot open shared object".
ImportError:libQTtest.so.4:cannot open shared object file:no such file or directory
Yes, but it does not say this is because "the library isnt shared with it"...
- 58.3k
5
votes
How to install OpenCV on Raspberry Pi 3 in Raspbian Jessie?
I will add to what @Technico.top has suggested. There's another method of installing OpenCV using emulation software to compile the software on your PC that doesn't require cross-complication.
This ...
5
votes
Is there a Raspbian image with OpenCV 3 pre-installed?
You can install opencv in a few minutes using piwheels:
sudo apt install libatlas3-base libwebp6 libtiff5 libjasper1 libilmbase12 libopenexr22 libilmbase12 libgstreamer1.0-0 libavcodec57 ...
- 2,431
5
votes
Accepted
Install opencv on Raspberry Pi 3 in a different way than compiling from source
Precompiled wheels of opencv-python and opencv-contrib-python for arm / python 3 are available from piwheels (www.piwheels.org). On current Raspbian Stretch this already pre-configured.
On other ...
- 3,496
5
votes
How to install OpenCV on Raspbian Stretch?
Following these directions from PyImageSearch fixes the problem. Those directions lack an easy copy-paste and have a lot of interspersed text, so I copy them here. I assume you already have Python3 ...
- 273
5
votes
Accepted
Run the program in the laptop and use the raspberry gpios, PWM to control servos
The pigpio library lets you control the GPIO of one or more networked Pis from a laptop. The laptop may be Windows, Mac, Android, or Linux based - in fact it can run any operating system as long as ...
- 70.4k
5
votes
Accepted
How can i install OpenCV on Raspberry Pi 4 (Raspbian Buster)?
You should use OpenCV from the default Raspbian Repository. It is tested and fits best into the Raspbian distribution without errors (I hope :). On Buster you will find with:
rpi ~$ apt list python*...
- 41.7k
3
votes
Accepted
Getting started with image processing using opencv in windows and using in raspberry pi
This will depend a lot based on what you want to do with the RPi.
If you want to run Windows 10 IOT... I'm admittedly unfamiliar with Windows 10 IOT, but I'll try to answer as best I can. You'll ...
- 11.9k
3
votes
Accepted
Pip exception while installing matplotlib on raspberry pi
I researched a little more an I solved it by using
pip install --no-cache-dir matplotlib
- 243
3
votes
Taking advantage of multiprocessing with OpenCV on raspberry Pi 2
If you compile the OpenCV library with the OpenMP option active in the cmake file (it is off by default), many algorithms will use multiple cores automatically, without you needing to change anything ...
- 225
3
votes
Taking advantage of multiprocessing with OpenCV on raspberry Pi 2
You should check out the multiprocessing library. If you have parts of you program that you can run in parallel, like processing multiple images and detecting a faces, you can simply define a process ...
- 131
3
votes
Accepted
Getting extremely low fps on Rpi 3 while image processing
First off, how are you determining that the CPU is only at 25-28%? htop is what I would use as it shows the usage of each core separately. sudo apt-get install htop, then htop to run it, q to quit.
...
- 3,362
3
votes
Accepted
Stereo Vision Using Compute Module: Pi camera synchronization
The Pi Compute Module's stereoscopic support causes captures (and video recordings) to produce frames containing images from both attached cameras, either side-by-side or top-and-bottom, depending on ...
- 3,978
3
votes
Accepted
How to use Raspberry Pi and Pi camera standalone like Arduino?
How can I use Raspberry Pi standalone which works just like Arduino?
You can't use it exactly like an Arduino, or at least not easily, and it would not be very desirable to do so. The Pi is a ...
- 58.3k
3
votes
Accepted
Unable to capture faces "y is not defined"
y is out of scope after leaving the for-loop which is why you get the not defined error with your imwrite. Check your intented program flow and indentation.
for (x,y,w,h) in faces:
cv2.rectangle(...
- 15.8k
3
votes
Accepted
Syntax error in python code for setMouseCallback() event
You are missing a (, try:
img = np.zeros((512, 512, 3), np.uint8)
- 247
3
votes
Accepted
Increasing fps of pi camera using OpenCV C++ implementation
As suggested in the comments, I think you need to set the frame geometry first and then set the frame-rate afterwards.
std::cout <<"\t[PARAM_FRAME_WIDTH] ";
if(!cap.set(CV_CAP_PROP_FRAME_WIDTH,...
- 256
3
votes
How to install opencv on raspbian jessie Lite?
Being two years old, that script has issues such as tying to an older version of OpenCV. Rather than downloading from Itseez's GitHub repo you're better off installing via the Raspbian package ...
- 2,884
3
votes
Is there a Raspbian image with OpenCV 3 pre-installed?
This, link may be helpfull. The image contains the last raspbian SO (Stretch), Ros and OpenCV
https://medium.com/@rosbots/ready-to-use-image-raspbian-stretch-ros-opencv-324d6f8dcd96
- 31
3
votes
Is there a Raspbian image with OpenCV 3 pre-installed?
Preparing a Raspberry Pi for OpenCV development is really time consuming, OpenCV takes hours to compile and a lot of other things have to be set up, so I just share my SD Card image here to speed up ...
- 31
3
votes
Is it necessary to release Raspberry Pi Camera before rebooting? If so how do I do it?
No, it is not necessary to stop the Pi camera before rebooting.
- 70.4k
3
votes
Is it necessary to release Raspberry Pi Camera before rebooting? If so how do I do it?
No there is no need to stop the camera before reboot.
Also preforming killall python is not doing you any good as the reboot is going to force the program to close anyway. If you are worried about ...
- 1,043
3
votes
Accepted
Pre-built OpenCV on Raspbian Buster
You just needed to run apt-get update and retry your command to install your desired package.
The issue was that one of the dependencies (libpango in this case) which needed to be installed along ...
- 46
3
votes
Getting stuck at 100% using make -j4 command while installing open cv on Rasbian buster , Raspberry Pi 4 B+
You don't tell us why do you want to compile OpenCV from source so I assume it is not necessary. We have seen many problems on this site doing it. You also try to compile for python version 2. This is ...
- 41.7k
3
votes
Raspberry 4 B not booting from raspberry stretch OS
The raspberrypi.org blog explained the need for Buster as follows: "The reason for this [new version of Rapbian] is that one of the important new features of Raspberry Pi 4 is that the open-source ...
- 179
Only top scored, non community-wiki answers of a minimum length are eligible