I use V4L2 to get the image data timestamp. When I get a frame, I use clock_getTime (CLOCK_MONOTONIC, &TV) to get the system power-up time. The two times will have a stable offset (15-25s).
I think the reasons are:
The TS of V4L2 comes from VI, and the TS of VI is calculated by TSC, which is the count of SC7, and TSC has a fixed time difference with MONOTONIC of the system
View CMD: “cat /sys/devices/system/clocksource clocksource0 / offset_ns”, found that it is the offset
How can I fix this problem?
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Does the application layer automatically add this offset every time?
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Change the timestamp in VI?