Why on Android the OpenCV camera is faster than the Android camera when capturing video

Question

In an Android project, I am trying to capture a video and process it in real time (e.g. Kinect). I tried using two methods: using OpenCV, continue to call mCamera.grab () and capture.retrieve (mRgba, Highgui.CV_CAP_ANDROID_COLOR_FRAME_RGBA); or Android camera, saving the image.

I feel that the OpenCV camera's ability to capture images faster than Android. But why?

Answer 1

OpenCV uses a hack to access low-level access to the Android camera. This avoids multiple copies of data and transitions between native and managed levels.