一个可用于编写v4l2 camera应用程序的库libv4l,里面除有常用的v4l2 ioctl调用的封装API外，还有yuv到rgb转换、rgb到yuv转换和jpeg decoder API。-V4l2 camera can be used for the preparation of an application' s database libv4l, which are commonly used in addition to the package v4l2 ioctl API c