Installing OpenCV in Ubuntu for Python 3
Installing OpenCV in linux for Python 3 is not that straight forward, so in this tutorial, we’ll go through the steps on how do we do it. We’ll be using a 64 bit Ubuntu 16.04 system, and Python 3.5 in this tutorial. (It should also work for Ubuntu 12.04++ onwards and Python 3.x)
(While copying the code over, do not include the >>> in the terminal: It’s just used to represent the python input.)
Contents [hide]
- 1 Packages Required
- 2 Copying the Python dev file
- 3 Downloading the OpenCV Source Code
- 4 Building
- 5 Installing
- 6 Checking
- 7 Python Libraries
- 8 Troubleshooting
- 9 References
Packages Required
Before compiling OpenCV, we have to download some packages for compilation.
Update the repository before installing the necessary packages.
|
1
|
sudo
apt
-
get
update
|
Once the update is done, we’ll proceed on to downloading the required packages to compile OpenCV.
- GCC
- CMake
- Git
- GTK+2.x or higher, including headers (libgtk2.0-dev)
- pkg-config
- ffmpeg or libav development packages: libavcodec-dev, libavformat-dev, libswscale-dev
|
1
|
sudo
apt
-
get
install
build
-
essential
cmake
git
libgtk2
.
0
-
dev
pkg
-
config
libavcodec
-
dev
libavformat
-
dev
libswscale
-
dev
|
Next, we will install the developer packages for python3. If you are using a different version of python, change it to python3.x-dev. (E.g. If you are using Python 3.3, use this instead: python3.3-dev)
|
1
|
sudo
apt
-
get
install
python3
.
5
-
dev
|
?
Copying the Python dev file
(If you using Python 3.2? or below, you can skip to the next step.)
As the pycofig.h header file is not in the typical place, we would have to copy the file to the expected location. Run the following code below:
|
1
|
python3
.
5
-
config
--
includes
|
The output would look something similar below:
|
1
|
-
I
/
usr
/
include
/
python3
.
5m
-
I
/
usr
/
include
/
x86_64
-
linux
-
gnu
/
python3
.
5m
|
The first part of the output is the expected location & the second part shows the current location of the config file. To solve this problem, we’ll copy the file from the current location to the expected location.
|
1
|
sudo
cp
/
usr
/
include
/
x86_64
-
linux
-
gnu
/
python3
.
5m
/
pyconfig
.
h
/
usr
/
include
/
python3
.
5m
/
|
?
Downloading the OpenCV Source Code
Make a new directory OpenCV-tmp in your Desktop, then change the directory into OpenCV-tmp . We will be using cloning the OpenCV source from Github into this folder.
|
1
2
3
|
mkdir
OpenCV
-
tmp
cd
OpenCV
-
tmp
git
clone
https
:
//github.com/Itseez/opencv.git
|
A opencv directory will be created in OpenCV-tmp . Rename opencv to opencv-3 .
?
Building
Before compiling the source, we have to generate the make file, so we will be using cmake.
Create a new directory build, which we will build the makefile in. Change the directory into it.
After that, run the cmake utility:
|
1
|
cmake
-
D
CMAKE_BUILD_TYPE
=
RELEASE
-
D
CMAKE_INSTALL_PREFIX
=
/
usr
/
local
.
.
/
opencv
-
3
|
If the command above does not work, you can try this alternative command: (Thanks to supermdguy for pointing this out!)
|
1
|
cmake
-
D
CMAKE_BUILD_TYPE
=
RELEASE
-
D
CMAKE_INSTALL_PREFIX
=
/
usr
/
local
.
.
|
?
After the makefile is generated, we will build the installation files:
|
1
|
make
-
j
$
(
nproc
--
all
)
|
This may take some time depending on your computer.
Side note:? We’ll split the make task via the -j argument, and the $(nproc -all) bash command to use all the processors available. Say if you want to only use 2 of the processors to run the make command, the command would look like this:
|
1
|
make
-
j2
|
?
Installing
Once the build is complete, we’ll install OpenCV by running the make file:
|
1
|
sudo
make
install
|
?
Checking
After OpenCV have finished installing, we have to check to ensure that OpenCV have been properly installed .
To do this, we’ll enter Python 3 and import cv2, and also check it’s version. If there are no errors, the output should look something like this:
|
1
2
3
|
>>>
import
cv2
>>>
cv2
.
__version_
_
'3.1.0-dev'
|
With this, you have successfully installed OpenCV for Python 3!
?
Python Libraries
Here are some of the python libraries that are commonly used in conjunction with OpenCV:
Numpy: Fundamental package for scientific computing
|
1
|
sudo
apt
-
get
install
python3
-
numpy
|
Matplotlib: 2D Plotting Library
|
1
|
sudo
apt
-
get
install
python3
-
matplotlib
|
?
Troubleshooting
ImportError: No module named ‘cv2’
- Did you miss the “Copying the Python dev file” step? (If you are running Python3.3+)?
- Make sure that you downloaded the correct python-dev packages. If you are not running Python 3.5, please change the dev packages accordingly. (E.g. Python 3.4 would be python3.4-dev )
- Recompile the makefile of the build directory. Make sure that you delete everything in the build directory before recompiling the makefile.
- If it still does not work, try reinstalling the required packages.
更多文章、技術(shù)交流、商務(wù)合作、聯(lián)系博主
微信掃碼或搜索：z360901061
微信掃一掃加我為好友
QQ號聯(lián)系： 360901061
您的支持是博主寫作最大的動力，如果您喜歡我的文章，感覺我的文章對您有幫助，請用微信掃描下面二維碼支持博主2元、5元、10元、20元等您想捐的金額吧，狠狠點擊下面給點支持吧，站長非常感激您！手機微信長按不能支付解決辦法：請將微信支付二維碼保存到相冊，切換到微信，然后點擊微信右上角掃一掃功能，選擇支付二維碼完成支付。
【本文對您有幫助就好】元
