How To Use Java With Ndk Android?

I am assuming that using the OpenCV code here: http://github.com/billmccord/OpenCV-Android#readme is the best way to use OpenCV on Android, with the NDK. I am still stuck as to

Solution 1:

Does your app require the C interface? OpenCV actually considers it deprecated / done with, the new API is C++. A port of this interface and sample calibration app are here: http://code.google.com/p/android-opencv/

It took me a while to get sold on the new C++, but I had to admit it was nice to not have to do cvReleaseMat() and go back and forth between IplImage and CvMat all the time. Opencv 2.1 doc: http://opencv.willowgarage.com/documentation/cpp/index.html

Solution 2:

Look at the Android samples within the ndk (hello-jni). They are in the apps directory of the NDK. They show how to import the library and call native methods. On C side of things you have to give your methods the proper jni naming conventions Java_...fully qualified java class name, make methods external and also include to make them accessable.

Also the docs directory of the NDK has all the documentation on building and running native code.