The low frequency of the pressure oscillation, as observed in the video to be sub 10Hz, suggests that this is a tall or long water column (thus heavy) traveling through a section of pipe with a large air cushion in it.
In contrasty, the frequency for water hammer from expansion of plastic piping (PEX, Poly, due to its elasticity) is much higher, well in the audible range and can sound like a screech, hum or buzz.
Banging or rattling sounds are caused by piping that is not fastened properly, can move freely as a result of water hammer, which then bangs against nearby surfaces like paneling, studs etc... The solution is to properly fasten the pipes, and install water arrestors nearby problematic faucets and valves (washing machine, dishwasher etc...)
If all the piping is rigid (e.g. copper) it can also be caused by water oscillating in & out of an expansion vat, often found near the water heater.
A further cause could be any pressurized flexible garden hoses, sprinkler attachments etc..
Air pockets may occur in the house piping if the piping was emptied for plumbing work, but then a section of piping never refilled with water after the system was recommissioned. To avoid water cushions, refill the system while keeping faucets open.
Look throughout your house for faucets or other outlets in odd locations (outside, storage/basement, closed off bathrooms), and for sections of pipe that are no longer used, e.g. capped off, but still connected. Unfortunately these may be hidden in walls, ceilings & floors.
Often a vertical run (and upwards) can have air trapped in it, which collects in it over time from air mixed with water entering the house. If there is a faucet at the end, you can open it to let the air out, until water pours out. This phenomenon is in fact exploited in capped-off dry vertical pipe columns used as water hammer arrestors.
If it's capped you'll have to uncap it. Close it off with a valve rather than a cap, so that you can repeat this after any future work or after air recollects in the pipe section.
You'll need to shut off the water main before uncapping, of course. If the section has a shutoff valve at the beginning of the run, you can close the valve to see if it reduces the oscillating effect.
Sometimes an unintended "high loop" (upside-down "U") can keep water trapped in it if the flow-through is slow compared to the diameter of the piping: water streams through as in an underground canal but the air cushion never gets pushed through. Make sure it can flush through with maximum flow for sufficiently long time.
