[−][src]Function k4a_sys_temp::k4a_image_get_system_timestamp_nsec
pub unsafe extern "C" fn k4a_image_get_system_timestamp_nsec(
image_handle: k4a_image_t
) -> u64
Get the image's system timestamp in nanoseconds.
\param image_handle Handle of the image for which the get operation is performed on.
\remarks Returns the system timestamp of the image. Timestamps are recorded by the host. They may be used for relative comparision, as they are relative to the corresponding system clock. The absolute value is a monotonic count from an arbitrary point in the past.
\remarks The system timestamp is captured at the moment host PC finishes receiving the image.
\remarks On Linux the system timestamp is read from clock_gettime(CLOCK_MONOTONIC), which measures realtime and is not impacted by adjustments to the system clock. It starts from an arbitrary point in the past. On Windows the system timestamp is read from QueryPerformanceCounter(), it also measures realtime and is not impacted by adjustments to the system clock. It also starts from an arbitrary point in the past.
\returns If the \p image_handle is invalid or if no timestamp was set for the image, this function will return 0. It is also possible for 0 to be a valid timestamp originating from the beginning of a recording or the start of streaming.
\relates k4a_image_t
\xmlonly