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If your glasses app is not using the camera, you can try the AR recording feature in the Hi Rokid app. If your app is using the camera, use Android screen capture for the display and record the real-world point of view separately.

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Why Hi Rokid recording may not work

The AR recording feature in the Hi Rokid app needs camera access. Vision-enabled apps also need camera access, so the two recording flows can compete for the same camera.

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Workflow

For some demo videos in the GlassKit repo, we record two sources:
  1. The glasses display with scrcpy, for example: scrcpy --no-audio --record ui.mp4
    • An adb connection is required, either over a cable or wirelessly.
  2. The real-world point of view with a separate head-mounted camera.
Then combine the two videos with ffmpeg or a video editor. A clap, tap, or obvious UI action at the beginning makes the videos easier to sync during editing.

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Combining the videos

This example combines one UI capture video and one POV camera video with ffmpeg. First, manually review both recordings, identify the exact timing offset, and trim the inputs so they start in sync. In the example below, those synced inputs are pov-trim.mp4 and ui-trim.mp4. 
ffmpeg -i pov-trim.mp4 -i ui-trim.mp4 -filter_complex "\
[1:v]pad=iw+4:ih+4:(ow-iw)/2:(oh-ih)/2:color=white,\
format=yuva444p,\
lumakey=threshold=0:tolerance=0.22:softness=0.01,\
format=rgba,\
lutrgb=r=0:g=255:b=0[ui0];\
[ui0][0:v]scale2ref=w=oh*mdar:h='min(ih-100,(iw-50)/mdar)':flags=lanczos[ui][pov];\
[pov][ui]overlay=50:50:alpha=straight:format=auto:shortest=1[v]" \
-map "[v]" -map "0:a?" \
-c:v libx264 -crf 18 -preset medium -pix_fmt yuv420p \
-c:a aac -b:a 192k -ar 48000 -ac 2 \
-movflags +faststart pov-and-ui.mp4
This overlays the UI capture near the top-left of the POV video. The lumakey and lutrgb steps make the black UI capture background transparent and recolor the UI overlay green so it is visible against the camera footage.

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POV recording gear

The current POV recording setup is:
  1. DJI Osmo Nano
  2. DJI Osmo Nano headband accessory
  3. DJI Mic Mini
The DJI Osmo Nano has a built-in mic, which is enough for voice and environmental sound. The DJI Mic Mini helps because the glasses speaker audio comes from the temple area and is easy to miss. Attach the mic around your ear so it captures the glasses audio more clearly. You do not need this exact setup. This is the setup used to record demos like this example video.

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Single in-app recording

The cleanest long-term solution is to implement recording inside the glasses app:
  1. Capture the screen or app UI with Android screen-capture APIs.
  2. Use the app’s own camera feed for both app logic and recording.
  3. Compose the UI and camera feed into one video inside the app.
That avoids asking the Hi Rokid app and your own app to use the camera at the same time. This is on the GlassKit roadmap.