cv::mat Thread handling

[Regalith]

Might want to take a look at properly handing over the cv::mat from the java to native thread in the app. That segfault is probably caused by calling processFrame in the UI thread and passing the cv::mat to a native thread. Wrapping that function call in

runOnUiThread(new Runnable() {
                @Override
                public void run() {
                    processFrame(img.getNativeObjAddr());
                }
            });

will solve the crash, but constrain everything to be run on the UI thread killing performance.

[nickw1]

@Regalith thanks for the suggestion. Sorry for the late reply btw, it's been a while since I've looked at this repo.