---
tags:
  - ct-reconstruction
  - sparse-view-ct
  - x-ray
  - pytorch
---

# NSP V3 strong-fusion Phase-1 prior

This release contains the best Phase-1 checkpoint from the V3 strong X-ray
fusion experiment. It was warm-started from the uploaded v27 prior and trained
on 500 LUNA16 cases (450 train / 50 held out).

## Checkpoint

- `best.pth`: best held-out checkpoint, selected at epoch 24
- Held-out Phase-1 PSNR: **34.862 dB**
- Input resolution: 128³ volume, 25 sparse projections at 64²
- X-ray fusion: strong fusion enabled
- Null branch: disabled

`config.json` records the exact training arguments. `train_log.txt`,
`phase1_v3_training_curve.png`, and `phase1_v3_training_metrics.csv` provide
the 30-epoch training record.

## Loading

Use the V3 `phase_v27/export_prior_v27.py` exporter in this repository and
pass `best.pth` as its checkpoint. The model architecture must be constructed
with the matching `config.json` fields before loading the checkpoint.