Re: using OpenCV4Android 2.4.9, "The import org.opencv.android cannot be resolved"

[Andrey Pavlenko]

Did you run 'make install' to get a kind of SDK in the <build>/install folder?

Did you tried 'Fix project properties' for the OpenCV library project?

I would also suggest you use '2.4' git branch, not 'master'.

[Andrey Pavlenko]

When you build OpenCV for Android you'd better use the command:

sh ./scripts/cmake_android.sh -DINSTALL_ANDROID_EXAMPLES=ON
cd build
make -j8  install/strip

then you'll have build/install folder containing OpenCV4Android SDK structured files. This doesn't affect your host (Linux) system libraries.

What you call the `OpenCV4Android 2.4.9` is just one of the revisions of OpenCV 'master' branch. I suggest you use '2.4' branch instead of 'master' (aka 2.4.9) unless you're going to submit a pull-request to OpenCV 2.5.

[Alexander Smorkalov]

Sources for all OpenCV versions are tagged by git. You need clone OpenCV git repo and then execute command "git checkout <opencv_version>" to checkout source code for exact release, i.e. "git checkout 2.4.2" for 2.4.2 release.
Also you can download source code archive from Github mirror. Github creates archives with all tags automatically.

[Andrey Pavlenko]

I am just curious, why the instruction does not mention it, if it is necessary?

Looks like the instructions is a bit outdated, which one did you use?

Since OpenCV-2.4.2-android-sdk has been built, I need to find one with source code. However, from the website, there is only one instruction to git clone it, and it is `OpenCV4Android 2.4.9. Would you advise me where I could find other ones (not built)

The OpenCV git repository contains all the active branches, use `git checkout 2.4` command to switch to the '2.4' branch or like Alexander noted `git checkout <versions>` to the tag of the particular release.