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 | 16,618 | 25,257 | x1.52 |
| training time (optimisation) | 17 min | 69 min | |
| held-out frames (within 0.3 s of a training frame) | 32 (10) | 32 (10) | |
| LPIPS on the fish (lower = closer to the photo) | 0.1373 | 0.1251 | -0.0122 |
| PSNR full crop (dB) | 28.39 | 28.39 | +0.00 |
| PSNR on the fish mask (dB) | 25.56 | 25.65 | +0.08 |
| sharpness ratio render / photo, grain-robust (1 = as sharp as the photo) | 0.296 | 0.535 | x1.81 |
| sharpness ratio, raw | 0.106 | 0.260 | x2.45 |
| sharp match (photo detail reproduced in place) | 0.271 | 0.238 | -0.033 |
| IoU with the SAM mask | 0.898 | 0.897 | -0.001 |
Verdict: better. LPIPS -0.0122, grain-robust sharpness x1.81 (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 | 58:00 – 68:00 |
| visits | 15: 58:35-58:38, 58:46-58:48, 58:54-58:57, 59:28-59:32, 59:38-59:42, 59:45-59:48, 59:56-59:59, 60:04-60:11, 60:24-60:30, 60:56-61:04, 61:14-61:15, 63:49-63:51, 64:10-64:14, 67:14-67:18, 67:31-67:34 |
| frames (10 fps) detected / kept | 488 / 478 |
| valid poses (10 fps) | 472 |
| frames with background plate | 460 |
| median size | 132.0 px |
| 30 fps frames / valid poses | 490 / 408 |
| method | 4D GS, fins + bending + tail (30 fps) |
| model shown | v2 (gs_v2, quality experiment rollout) |
| iterations | 12000 |
| gaussians | 25257 |
| training time | 69 min |
| trainer validation PSNR full / masked | 28.9 / 20.6 dB |
| trainer validation IoU vs SAM mask | 0.914 |
| near-fish band PSNR (fins) | 29.9 dB |
| production status | done |
| visual note (curation) | banded wrasse (pale vertical bar) |






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