Verdant — on-device plant model bundle
Two ONNX classification heads used by the Verdant mobile plant-diary app.
All inference runs locally on the phone; user photos never leave the device.
The app downloads this bundle once on first launch and caches it.
| Head | Arch | File | Precision | Size | Classes |
|---|
| Species | MobileViT | species_mobilevit_int8.onnx | int8 | 5.4 MB | 47 houseplants |
| Leaf condition | MobileNetV2 | disease_mobilenetv2_fp32.onnx | fp32 | 9.0 MB | 38 (12 healthy) |
config.json carries the full label maps, preprocessing parameters
(resize/crop/channel order/normalization) and per-head confidence thresholds.
version.json carries sizes and SHA-256 checksums for resumable, verified
downloads.
Quantization notes
- Species (MobileViT → int8): dynamic int8 quantization is a clean win —
3.6× smaller with top-1 parity vs fp32 (40/40 agreement on random inputs).
Transformer matmuls quantize well.
- Leaf condition (MobileNetV2 → fp32, kept): dynamic int8 quantization of
MobileNetV2's depthwise convolutions collapsed accuracy (0/60 top-1
agreement) and ran slower on CPU, so this head ships fp32 — consistent with
the project spec (fp32 default, quantization optional).
Preprocessing (from config.json)
Species: shortest-edge resize 288 → center-crop 256 → x/255 → BGR channel
order, no mean/std.
Leaf: shortest-edge resize 256 → center-crop 224 → x/255 → RGB → normalize
mean/std = 0.5.
Output is raw logits; apply softmax. If top-1 probability is below the head's
confidence_threshold, show candidate alternatives or an "unsure" state and
prompt the user to retake the photo.
Provenance & limitations
MVP heads are derived from public checkpoints:
dybdyb/mobilevit-houseplants
(species) and
linkanjarad/mobilenet_v2_1.0_224-plant-disease-identification
(leaf condition, PlantVillage-trained).
The leaf-condition head is trained on lab-style crop images. Per the project
spec, it must be revalidated and retrained on field data (PlantDoc + own
collection) before production — lab accuracy does not reflect real-world
phone photos. Species coverage is a starter set of popular houseplants and
grows iteratively.
