gs_final, 4000 iterations) with 12000 iterations and a gaussian cap of 100,000 — the only change of the quality experiment that passed its review. Other changes (frame selection, water and motion-blur models, white balance, lossless crops) did not. The two turntables play in sync (same orbit and timing).
| metric | v1 gs_final | v2 gs_v2 | change |
|---|---|---|---|
| iterations | 4000 | 12000 | |
| gaussians | 18,790 | 40,251 | x2.14 |
| training time (optimisation) | 19 min | 73 min | |
| held-out frames (within 0.3 s of a training frame) | 21 (10) | 21 (10) | |
| LPIPS on the fish (lower = closer to the photo) | 0.1882 | 0.1589 | -0.0293 |
| PSNR full crop (dB) | 24.62 | 24.69 | +0.07 |
| PSNR on the fish mask (dB) | 19.26 | 19.44 | +0.18 |
| sharpness ratio render / photo, grain-robust (1 = as sharp as the photo) | 0.321 | 0.468 | x1.46 |
| sharpness ratio, raw | 0.137 | 0.281 | x2.05 |
| sharp match (photo detail reproduced in place) | 0.145 | 0.251 | +0.105 |
| IoU with the SAM mask | 0.901 | 0.897 | -0.004 |
Verdict: better. LPIPS -0.0293, grain-robust sharpness x1.46 (sharper). Differences below 0.0034 LPIPS or x1.12 sharpness are within the run-to-run noise of training.
Held-out frames: fixed per fish (work/quality_exp/<fish>/heldout.json), evaluated identically for both models (test-time fit of pose, colour and bending with the gaussians frozen). Both models were trained on all frames of the same data set, so held-out frames near a training frame favour both equally; this is a like-for-like comparison of the two recipes, not a generalisation test.
Family: Labridae 100%, Serranidae 0%, Pseudochromidae 0% · agreement across crops 100% · 64 crops · bioclip-2.5 (hf-hub:imageomics/bioclip-2.5-vith14, open_clip, zero-shot)

| window | 02:00 – 12:00 |
| visits | 12: 02:46-02:50, 04:16-04:19, 05:12-05:17, 05:41-05:44, 07:55-08:03, 08:13-08:19, 08:33-08:36, 08:40-08:42, 08:45-08:52, 08:56-08:59, 09:19-09:21, 09:27-09:30 |
| frames (10 fps) detected / kept | 491 / 461 |
| valid poses (10 fps) | 426 |
| frames with background plate | 420 |
| median size | 239.0 px |
| 30 fps frames / valid poses | 724 / 592 |
| method | 4D GS, fins + bending + tail (30 fps) |
| model shown | v2 (gs_v2, quality experiment rollout) |
| iterations | 12000 |
| gaussians | 40251 |
| training time | 73 min |
| trainer validation PSNR full / masked | 25.1 / 18.6 dB |
| trainer validation IoU vs SAM mask | 0.884 |
| near-fish band PSNR (fins) | 27.0 dB |
| production status | done |
| visual note (curation) | checkerboard wrasse, Halichoeres hortulanus likely |






point_cloud.ply (canonical 3D gaussians) · poses_refined.json · model.pt (incl. per-frame 4D params) · species.json · previous version v1: gs_final point_cloud.ply