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Target Cam - Raspberry Pi NDI Options

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I’d publish the build log but it’s got sooooo much personal info it in so fuck off

Goal: USB-powered, WiFi NDI broadcaster at 1280x720 @ 15–30fps. Physically tiny, single USB charger into the wall.

Existing NUC setup documented at log - target cam nuc — the software stack is identical, just compiled for ARM instead of x86_64.

Pi Options

Pi Zero 2W — Smallest possible

  • Quad-core Cortex-A53 @ 1GHz, 512MB RAM
  • Power: micro USB (PWR IN port) — any USB charger works, draws ~1.5–2W under load
  • Webcam: USB OTG adapter into the second micro USB port
  • WiFi: built-in
  • Size: credit card, genuinely tiny
  • Concern: 1GHz is tight for 720p @ 30fps NDI. Likely fine at 15fps, worth testing at 30fps — the YUYV→UYVY byte swap is cheap but NDI has overhead
  • Cost: ~$20 AUD

Pi 3B+ — Middle ground

  • Quad-core Cortex-A53 @ 1.4GHz, 1GB RAM
  • Power: micro USB, draws ~2–3W — needs a decent charger (2.5A+)
  • Webcam: full-size USB-A port, no adapter needed
  • WiFi: built-in
  • 720p @ 30fps: should handle it comfortably
  • Cost: ~$50–60 AUD (harder to find new)

Pi 4 (2GB) — Safe bet

  • Quad-core Cortex-A72 @ 1.8GHz, 2GB RAM
  • Power: USB-C, draws ~3–4W — needs a 5V/3A USB-C charger
  • Webcam: full-size USB-A port
  • WiFi: built-in
  • 720p @ 30fps: no issues, headroom to spare
  • Cost: ~$60–80 AUD

Recommendation

Start with Pi Zero 2W if you want the smallest possible footprint — test at 15fps first, try 30fps and see. If it struggles, Pi 4 is the reliable fallback.

For the power setup on Zero 2W:

  • USB charger → PWR IN (left micro USB port)
  • Webcam → micro USB OTG adapter → USB port (right micro USB port)
  • One cable in the wall, one cable to the webcam, done

Setup — Same as NUC, ARM Version

OS: Raspberry Pi OS Lite (64-bit) — headless, no desktop needed. Configure WiFi during flash via Raspberry Pi Imager (Advanced Options).

1. Install build tools

sudo apt update && sudo apt install -y curl gcc make v4l-utils

2. Install NDI SDK (ARM64)

wget https://downloads.ndi.tv/SDK/NDI_SDK_Linux/Install_NDI_SDK_v6_Linux.tar.gz -O /tmp/ndi-sdk.tar.gz
cd /tmp && tar -xzf ndi-sdk.tar.gz
yes | PAGER=cat sh /tmp/Install_NDI_SDK_v6_Linux.sh
 
# ARM64 — note aarch64 instead of x86_64
sudo cp -P ~/NDI\ SDK\ for\ Linux/lib/aarch64-linux-gnu/* /usr/local/lib/
sudo cp ~/NDI\ SDK\ for\ Linux/include/* /usr/local/include/
sudo ldconfig
sudo ln -sf /usr/local/lib/libndi.so.6 /usr/local/lib/libndi.so.5

3. Compile ndi-webcam

Same C source as the NUC (see log - target cam nuc). Change NDI_NAME at the top to something like "Pi Target Cam".

gcc -O2 -Wall -I/usr/local/include -o /tmp/ndi-webcam /tmp/ndi-webcam.c -L/usr/local/lib -lndi -Wl,-rpath,/usr/local/lib
sudo install -m 755 /tmp/ndi-webcam /usr/local/bin/ndi-webcam

4. Systemd service

Same service file as the NUC — copy it over, then:

sudo systemctl daemon-reload
sudo systemctl enable --now ndi-webcam

5. Set a static IP

Either via your router’s DHCP reservation (easiest) or via /etc/dhcpcd.conf:

interface wlan0
static ip_address=192.168.1.XX/24
static routers=192.168.1.1
static domain_name_servers=192.168.1.1

FPS Tweak

To drop to 15fps, edit the #define FPS 30 line in the C source to 15, recompile, reinstall, restart service. Halves the NDI bandwidth and CPU load.

Notes

  • If the webcam doesn’t appear at /dev/video0 run v4l2-ctl --list-devices to find the right path
  • NDI discovery is multicast — Pi and receiving machine need to be on the same subnet/WiFi network
  • If multicast is blocked, NDI Tools on the receiving end has a manual source entry option

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