publish

content/log/2025/construction-site-surveillance.md

@@ -1,7 +1,6 @@
 ---
 title: "Construction site surveillance"
-date: 2025-02-24T22:01:14+02:00
-draft: true
+date: 2025-04-01T14:26:00+02:00
 ---
 
 I am building a house, for which I decided I need a surveilance cameras. I have
@@ -59,12 +58,18 @@ There are two codec choices, mostly:
   found in Wikipedia][14], it was used by 91% of video industry developers as
   of September 2019. Every screen-equipped device that I tried can play it.
 - *H.265* (a.k.a. _HEVC_) is a royalty- and patent-ridden codec which offers
-  25-50% better compression ratios[15]. In my experience, the compression ratio
-  was over 50%. It is amazing for transfer, un-playable on everything I've
-  tried except Google Chrome browser on Android[^1].
-- Footnote: *H.264+*, *H.264B*, *H.264H* and similar. They are "close"
-  derivatives of H.264. Software support is hit-or-miss, so I mostly ignore
-  those.
+  25-50% [better compression ratios][15]. In my experience, the compression
+  ratio was over 50%. It is amazing for transfer, un-playable on everything
+  I've tried except Google Chrome browser on Android[^1].
+- *AV1* seems to be anecdotally on-par with H.265 and is not patent-ridden.
+  Camera cannot stream it, but lack of patent problems implies, it should be
+  good for recordings. However:
+  - I was not able to (easily) setup go2rtc with AV1.
+  - The 5-minute experiments yielded similar bitrates for similar quality. In
+    the end, I decided it's not worth the hassle until go2rtc offers a packaged
+    configuration for it.
+- *H.264+*, *H.264B*, *H.264H* and similar. They are "close" derivatives of
+  H.264. Software support is hit-or-miss, so I mostly ignore those.
 
 # Picking the camera
 
@@ -83,8 +88,7 @@ There are a few variables you may want to check:
   known about it, or at least read the Dahua part, before purchasing mine.
 
 Note that most cameras are designed and manufactured in China. Which,
-unsurprisingly, have [bad reputation in the Chinese-controlled areas][1]. I
-also found out about it only while researching open-source NVRs.
+unsurprisingly, have [bad reputation in the Chinese-controlled areas][1].
 
 # Network Video Recorder
 
@@ -102,20 +106,40 @@ two options for an NVR:
   [home server]({{< ref "log/2023/nixos-subjective" >}}), I am self-hosting my
   NVR.
 
+## Moonfire NVR
+
 *Moonfire NVR* seems like the simplest of the bunch: low hardware requirements
 (raspberry pi 2!), minimal number of features. Cons: does not have object
 detection, not even "in theory". I have relatively powerful hardware in the
 closet and want object detection for it.
 
+Moonfire NVR's interface is ncurses-based, similar to how Linux kernel is
+configured. In opinion, for end-user product, one either offers file-based
+configuration, or web-based configuration directly in the browser. Many
+projects do both (e.g. home-assistant, frigate). This is the first ncurses-based
+configuration for a consumer product. Which makes me wonder what their audience
+is.
+
+
+{{<img src="_/2025/construction-site-surveillance/moonfire-config.png"
+    alt="Moonfire-NVR ncurses-based configuration dialog"
+    hint="graph"
+    >}}
+
+Once configured, the recordings are printed as a timestamped list. Which is
+good if you know the time upfront, but is not great for discovery.
+
+{{<img src="_/2025/construction-site-surveillance/moonfire-nvr.png"
+    alt="Moonfire-NVR web dialog with a list of recordings"
+    hint="graph"
+    >}}
+
+## Setting up Frigate
+
 *Frigate* seems to be what the kids use these days. Documentation is extensive,
 though sometimes not very accurate, but [their forums][13] compensate for it.
 It took a few evenings to get it to work, and it works.
 
-*ZoneMinder* is the oldest and most established. I learned about it only after
-having set up Frigate.
-
-## Setting up Frigate
-
 A few tips before you get started:
 
 - for object detection you will need hardware support. Look at [recommended
@@ -123,16 +147,13 @@ A few tips before you get started:
   OpenVINO too.
 - start with go2rtc from the get-go. I had to re-configure all the Frigate
   streams, which was way more annoying than it's worth if you start with
-  go2rtc.
-- as of writing I have [a performance problem with detectors using lots of
-  CPU][7] that nobody seem to be able to reproduce. I am hopeful Frigate 0.15
-  will fix this.
+  go2rtc. Saved a lot of bandwidth, too. More on that later.
 
 ## Connecting the camera
 
 I bought [Teltonika Rutx11][8] 4G router/wifi modem that will fit in the
 [camera junction box][9]. Antennas will be outside:
-- [External 4G antenna from Mikrotik][10]
+- [External 4G antenna from Mikrotik][10].
 - [Wi-fi dual-band magnetic sma antenna from Teltonika][11].
 
 I purchased an unlimited 4G plan from an ISP that has good connectivity in the
@@ -140,14 +161,24 @@ area. Then connected the Rutx11 via tailscale/[headscale][12]. Using tailscale
 I can connect to the camera directly from both my NVR and all personal devices,
 a yet another tailscale+headscale recommendation.
 
+I disabled outgoing connections from the camera on the router. As a nice
+side-effect, I have a _really nice_ WiFi hotspot in the construction site.
+
 ## Bandwidth and codec considerations
 
 Two camera streams (`2688x752` and `1920x1080`), encoded in h.265 consume
-around 1.8Mb/s 24/7. Both streams are transcoded to h.264 via go2rtc and then
-sent over to Frigate and live view. and
+around 2Mb/s 24/7. Both streams are transcoded to h.264 via go2rtc and then
+sent over to Frigate and live view. Then recorded as H.264. Recordings for both
+cameras take ~21-24GiB/day.
 
 Every 5 minutes a separate process captures a full-resolution picture of both
-cameras: `5376x1520` and `2560x1440`.
+cameras: `5376x1520` and `2560x1440`. I have a bunch of timelapses already! If
+we meet in person, I will happily show.
+
+{{<img src="_/2025/construction-site-surveillance/grafana-traffic.png"
+    alt="Grafana dashboard showing ~2Mb/s downlink and ~100Kb/s uplink over tailscale0 interface"
+    hint="graph"
+    >}}
 
 Using exactly the same parameters (resolution, fps), but with h.264, the
 bandwidth grows to 11 Mb/s. Which may not sound like a lot with today's fiber
@@ -155,6 +186,7 @@ everywhere, but is considerable on a 4G connection.
 
 Since the home server has a graphics card, it can use hardware acceleration for
 video encoding and decoding. Thanks to proliferation of online video platforms,
+those decoders and encoders are available on even the cheapest hardware.
 
 It takes ~5-10% of a single CPU core to transcode a stream, depending on the
 resolution. In my case, I am transcoding 4 streams (2 cameras, "low" and "high"
@@ -165,13 +197,19 @@ Once the house is complete and I move NVR to the same physical network, I will
 change the encoding to h.264, stop transcoding and use more video bandwidth
 locally.
 
+# Final notes
+
+With the current open-source NVR ecosystem and the price of consumer-grade
+surveilance cameras (low hundreds of €), I highly recommend setting one up if
+you are building something. It takes a few weeks to learn all the dusty
+corners, but, in my opinion, in the end it's worth it.
+
 [1]: https://uhrp.org/statement/hikvision-and-dahua-facilitating-genocidal-crimes-in-east-turkistan/
 [2]: https://web.archive.org/web/20250221205936/https://ipcamtalk.com/wiki/ip-cam-talk-cliff-notes/
 [3]: https://frigate.video
 [4]: https://github.com/scottlamb/moonfire-nvr
 [5]: https://zoneminder.com/
 [6]: https://docs.frigate.video/frigate/hardware
-[7]: https://github.com/NixOS/nixpkgs/issues/381280
 [8]: https://teltonika-networks.com/products/routers/rutx11
 [9]: https://www.dahuasecurity.com/products/All-Products/Accessories/Camera-Accessories/Camera-Mounts/Junction-Boxes/PFA126
 [10]: https://mikrotik.com/product/mant_lte_5o