When any dash camera states that it draws "very low power" in parking mode, it will only detect impact events. Video(s) created will not be buffered since they start recording within 1-to-2 seconds after the impact is detected in low power impact detection parking mode.
The current generation of VIOFO dash cameras that support low power impact detection [LPID] [A329S series], consume 30 mA to 43 mA depending on how many cameras are connected. That somewhat elevated low power draw level is a vast improvement compared to the VIOFO traditional parking modes [Auto Event Detection, Time-Lapse, Low Bitrate]. Will the 43 mA power draw greatly reduce the amount of time your vehicle's battery can power it compared to a dash camera that only draws 1 mA in its low power parking mode, yes it can.
I'm going to use my dash camera battery pack projected parking mode time estimates with a 96 Wh battery pack.
My time estimates are based on a simplifying assumption that 100% of the dash camera battery pack's stored capacity is available for use. If the dash camera's hardwire kit has its own low voltage protection feature, the hardwire kit's low voltage protection feature will almost always turn off power to the dash camera before the dash camera battery pack would have turned its DC output power to the dash camera/kit. You might be able to get 85% to 90% of the estimated time based on those restrictions.
A329S consuming 30 mA in LPID: 10 days 12 hours 37 minutes
A329S consuming 35 mA in LPID: 9 days 2 hours 10 minutes
A329S consuming 43 mA in LPID: 7 days 9 hours 46 minutes
Other dash camera consuming 1 mA in its low power impact detection mode: 400 days [in theory]
LPID - VIOFO Style:
While the A329S dash camera is in LPID, it will boot and start recording 60-second videos within 1-to-2 seconds of detecting the impact event. It then returns to low power mode waiting for another impact event.
LPID - Others [VUEROID, BlackVue ELITE, Thinkware U3000/U3000 Pro]:
Some of the other dash cameras with a similar low power impact detection parking mode will approach the situation a little different. When first entering low power parking mode, the dash camera doesn't immediately go into low power impact detection parking mode. The dash camera will go into a monitoring and/or recording mode for a short period of time. If an impact occurs during this initial monitoring period, it will create buffered recording(s) for qualifying impact/motion events. When this initial monitoring period finishes, the dash camera does go into the 1 mA low power mode and it waits for an impact to occur.
If a qualifying impact event is detected, the dash camera will start recording within 1-to-2 seconds. When the unbuffered impact video(s) have finished recording, the dash camera does not go back to low power mode immediately. It will monitor for a period of time waiting for qualifying motion/impacts [depending on the make/model/parking mode/sensitivity settings]. If a qualifying impact/motion event takes place during this monitoring period, buffered video(s) will be created. When this monitoring period finishes, the dash camera will go back into the low power draw parking mode and start the cycle again [waiting for an impact event].
The monitoring periods before/after the LPID low power draw time periods consume significantly more power than the LPID 1 mA portion of this parking mode. Depending on how many impacts occur, the theorectical 400 day time estimate I listed above can be greatly reduced. All dash cameras will consume far more power while it's creating videos due to the LPID detected impact event. The dash cameras with additional monitoring periods before/after LPID mode will consume a few hundred milliamps while in those monitoring periods.