Constant realsense_sys::rs2_frame_metadata_value_RS2_FRAME_METADATA_GAIN_LEVEL

pub const rs2_frame_metadata_value_RS2_FRAME_METADATA_GAIN_LEVEL: rs2_frame_metadata_value = 4;

< A relative value increasing which will increase the Sensor's gain factor.
When AE is set On, the value is controlled by firmware. Integer value