Install opencv on Raspberry Pi 3 in a different way than compiling from source

Question

I am using Raspbian Stretch on my RPi 3, I wanted to install OpenCV on it.
I did this before by following the instructions detailed here . The problem is that this takes a very long time.
Lately, I've been looking in the internet, so I found in this link that installing Opencv only needs to run these commands pip install opencv-python and pip install opencv-contrib-python. I tried it on Ubuntu with my PC and it worked well.
So my question is: is it possible to install Opencv on a RPi 3 by just running these commands instead of compiling it from source?

• Jan Hus: I really do not know , my fault, how to respond, but who or what is stopping you to try it ? Secondly - if the "manual: states it will take OpenCV time to install due to dependencies - why cannot just accept that?
• singrium: Unfortunately, it is a bit late now.. I am already in the last step of the 'usual' method which is compiling from source. So at least I have to wait till it finishes to try this one.
• Jan Hus: Have you favorite snack / beverage in the meantime. Cheers
• singrium: As I read in this link: raspberrypi.stackexchange.com/questions/77307/…, precompiled binaries work only for some specific architectures (X86 and X86_64 but not ARM), which means that the only available solution to install Opencv on RPi is to compile it from source.
• Dirk: @singrium: precompiled wheels of opencv-python and opencv-contrib-python for arm / python 3 are available from piwheels (www.piwheels.org)

Answer 1

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 distros (such as Raspbian Jessie) it can easily be added by creating the file '/etc/pip.conf' containing:

[global]
extra-index-url=https://www.piwheels.org/simple

See also Installing scipy 1.0.0 in python3 environment

• singrium: Di you try installing Opencv using piwheels before? As I said before, I am in the last step of compiling Opencv from source and I am afraid that if I abort it now and try piwheels it will not work.
• Dirk: Not 'in anger', meaning I downloaded it, but I cannot test if it's actually working ATM. Maybe you can create a virtual environment and try to download it in that environment.
• Noah Pentecost: This doesn’t work either; same "no matching distribution error"
• Dirk: @NoahPentecost on what model Pi / OS + version / Python version? And what is the exact command you use?
• Eric Platon: This worked on a RasPi 3 Model B v1.2, under Stretch. This is a fresh install, and I do not understand the claim that Stretch checks PiWheels out of the box. If really pre-configured, the system images we get are broken. Anyway, thanks @Dirk for compiling a solution (note that this solution checks PiWheel after, not before PyPi, as expected in some Stretch documentations).