SSD MobileNet V1 on reComputer R Series (CM5 + Hailo-8)

SSD MobileNet V1 is the classic TensorFlow SSD detector with a MobileNet V1 backbone. It detects 80 COCO object classes on Hailo-8. NMS runs on-chip (Hailo HPP, meta_arch=ssd) with predefined anchors, so the host only parses the post-NMS tensor.

This page targets reComputer R Series (CM5 + Hailo-8) with a PCIe Hailo-8 accelerator.

Model Info

The accuracy value is Hailo's Model Zoo reference. It is not a benchmark measured on CM5.

Hardware and Host Setup

Install the Hailo-8 packages on the host and confirm that the driver and device are ready before starting the container:

sudo apt update
sudo apt install hailort hailort-pcie-driver python3-hailort
sudo reboot

# After reboot
hailortcli --version
hailortcli fw-control identify
ls -l /dev/hailo0

The expected HailoRT version for this image is 4.23.x.

Run With Demo Video

sudo docker run --rm \
  --name cm5-hailo8-ssd-mobilenet-v1 \
  --privileged \
  --net=host \
  -e PYTHONUNBUFFERED=1 \
  --device /dev/hailo0:/dev/hailo0 \
  -v /usr/lib/libhailort.so.4.23.0:/usr/lib/libhailort.so.4.23.0:ro \
  -v /usr/lib/libhailort.so:/usr/lib/libhailort.so:ro \
  ghcr.io/seeed-projects/recomputer-hailo8-cv/ssd_mobilenet_v1:latest \
  python web_detection.py --model_path model/ssd_mobilenet_v1.hef --video_path video/test.mp4

Open http://<Board_IP>:8000 to view the web preview.

USB Camera Mode

sudo docker run --rm \
  --name cm5-hailo8-ssd-mobilenet-v1 \
  --privileged \
  --net=host \
  -e PYTHONUNBUFFERED=1 \
  --device /dev/hailo0:/dev/hailo0 \
  --device /dev/video0:/dev/video0 \
  -v /usr/lib/libhailort.so.4.23.0:/usr/lib/libhailort.so.4.23.0:ro \
  -v /usr/lib/libhailort.so:/usr/lib/libhailort.so:ro \
  ghcr.io/seeed-projects/recomputer-hailo8-cv/ssd_mobilenet_v1:latest \
  python web_detection.py --model_path model/ssd_mobilenet_v1.hef --camera_id 0

REST API

Prediction endpoint:

POST http://<Board_IP>:8000/api/models/ssd_mobilenet_v1/predict

Example image request:

curl -X POST "http://<Board_IP>:8000/api/models/ssd_mobilenet_v1/predict" \
  -F "file=@test.jpg"

Implementation Notes

• The HEF runs NMS on-chip (device_pre_post_layers: nms=true); the app only parses the post-NMS tensor (per the official tf_postproc_nms), so nms_thresh is ignored (API parity only).
• Post-NMS rows are [ymin, xmin, ymax, xmax, score, ...], normalized to [0,1] of the 300x300 letterboxed input; the app scales to pixels and un-letterboxes.
• normalize_in_net with mean=127.5/std=127.5 (classic SSD normalization (pixel-127.5)/127.5); the app feeds raw uint8 RGB pixels after letterboxing — no manual normalization.
• HailoRT returns the NMS vstream as a ragged per-class list (NMS-by-score); the parser handles that plus object/dense layouts. First inference logs the raw type/shape so it can be verified on hardware.
• Class mapping: cls_id (0..89) → COCO category ID cls_id+1 (labels_offset=1); the 10 unused COCO IDs are "N/A" and not drawn.
• Defaults: confidence 0.25, IOU 0.45 (IOU has no effect — NMS on-chip). Model Zoo eval uses 0.3 / 0.6 — lower the confidence slider to inspect more.

Development Notes

• Source module: src/rpi5_hailo8_ssd_mobilenet_v1/
• Dockerfile: docker/hailo8/ssd_mobilenet_v1.dockerfile
• Container: ghcr.io/seeed-projects/recomputer-hailo8-cv/ssd_mobilenet_v1:latest
• The module uses the HailoRT 4.23 VStreams API and a Hailo-8-specific HEF.
• Family: ssd (variants ssd_mobilenet_v1 / ssd_mobilenet_v2 planned); this is the V1 build.