raspicam 这个库是基于 C++ 的。
https://sourceforge.net/projects/raspicam/files/

* Main features:
- Provides class RaspiCam for easy and full control of the camera
- Provides class RaspiCam_Cv for easy control of the camera with OpenCV.
- Provides class RaspiCam_Still and RaspiCam_Still_Cv for controlling the camera in still mode
- Easy compilation/installation using cmake.
- No need to install development file of userland. Implementation is hidden.
- Many examples

能不能实现 binning 需要研究下。