hello,
I worked on a non-free app for Android that uses video camera and some OpenCV processing to make sound with libpd
It was based on ScenePlayer by Peter Brinkmann.
Basically, the global layout was modified to implement a Camera.PreviewCallback then with the onPreviewFrame(byte[], Camera) method I get the video data and pass it to a JNI that does the processing thanks to OpenCV4Android
Then the JNI talks with Pd tanks to some global variables and callback functions.
Note that I can't find any way to access the android camera without displaying a preview image.
I made an external that works on Linux, Mac OS, Windows and Android.
Thus people can work with their workstation on patch and then download it to the phone.
Unfortunately I'm not able to share the source code of this app since it's not free.
cheers
antoine