PHerc.1667-iteration-2

PHerc.1667-iteration-2

Trained on segment l_2 with l_2_inklabels2.png (8,970 tiles).

Ablation 2/5 — 8,970 training tiles (~3x ink1).

This is one of six sibling models released together — five label ablations on segment l_2 (ink1–ink5, increasing label coverage) and one cross-segment baseline (ink0). The full family is listed at the bottom of this card.

Preview

l_2 (training segment) prediction with the training label overlaid in magenta, and l_5 (held-out segment) prediction. All panels are downsampled 16× and rotated 180° to match the publication-figure convention. The full-resolution last.ckpt outputs are at 43008 × ~30000 voxels.

Architecture in one paragraph

A 3-D volumetric input (B, 1, 62, 256, 256) is encoded by a ResNet3D-50 backbone (Hara, Kataoka & Satoh, 2018; initialised from the Kinetics-700 release r3d50_KM_200ep.pth with conv1 weights summed across RGB → 1 grayscale channel). Each of the four backbone stages is collapsed along the z (depth) axis with torch.max, producing a 2-D feature pyramid {(256,64,64), (512,32,32), (1024,16,16), (2048,8,8)}. A small 2-D U-Net decoder upsamples coarse-to-fine with concatenated skip connections; a 1×1 conv head produces a single sigmoid logit channel at quarter resolution (B, 1, 64, 64). Training uses 0.5·Dice + 0.5·SoftBCE against the label down-interpolated to 64×64.

Quick start

import torch
from transformers import AutoModel

model = AutoModel.from_pretrained(
    "YoussefMoNader/PHerc.1667-iteration-2",
    trust_remote_code=True,
).eval().cuda()

# Input: float32, shape (B, 1, D=62, H=256, W=256).
# Intensity should already be in roughly [0, 1] (the training pipeline
# clipped raw uint8 layers to [0, 200] then applied Normalize(mean=0, std=1)
# which keeps the magnitude small).
x = torch.randn(1, 1, 62, 256, 256, device="cuda")

with torch.no_grad():
    out = model(x)

print(out.logits.shape)                        # torch.Size([1, 1, 64, 64])
prob = torch.sigmoid(out.logits)               # ink probability per pixel

Full-segment inference (tiling)

The model only sees 256×256 windows. For a full scroll segment you need to slide the window across the (padded) layer stack and average overlapping predictions:

import numpy as np, cv2, torch
import torch.nn.functional as F
from transformers import AutoModel

model = AutoModel.from_pretrained(
    "YoussefMoNader/PHerc.1667-iteration-2", trust_remote_code=True,
).eval().cuda()

WINDOW, STRIDE = 256, 128       # 128 = 2x oversample; 64 for 8x oversample
D = 62                           # number of z-layers

# image: (H, W, D) uint8 stack of the 62 layers, padded to multiples of 256.
# fmask: (H, W) uint8 fragment mask (0 = outside, 255 = inside).
H, W, _ = image.shape
mask_pred  = np.zeros((H, W), dtype=np.float32)
mask_count = np.zeros((H, W), dtype=np.float32)

with torch.no_grad():
    for y in range(0, H - WINDOW + 1, STRIDE):
        for x in range(0, W - WINDOW + 1, STRIDE):
            if np.any(fmask[y:y+WINDOW, x:x+WINDOW] == 0):
                continue
            tile = image[y:y+WINDOW, x:x+WINDOW]            # (256,256,62)
            t = torch.from_numpy(tile).permute(2, 0, 1)     # (62,256,256)
            t = t.unsqueeze(0).unsqueeze(0).float().cuda()  # (1,1,62,256,256)
            logits = model(t).logits                        # (1,1,64,64)
            prob   = torch.sigmoid(logits)
            prob   = F.interpolate(prob, scale_factor=4,
                                   mode="bilinear").squeeze().cpu().numpy()
            mask_pred[y:y+WINDOW, x:x+WINDOW]  += prob
            mask_count[y:y+WINDOW, x:x+WINDOW] += 1.0

pred = np.divide(mask_pred, mask_count,
                 out=np.zeros_like(mask_pred),
                 where=mask_count != 0)
cv2.imwrite("prediction.png", np.clip(pred * 255, 0, 255).astype(np.uint8))

Training summary

Files

The HuggingFace weights are bit-perfect identical to the original PyTorch-Lightning checkpoint (verified max abs diff = 0.0e+00 on identical inputs). Use model.safetensors for AutoModel.from_pretrained; use last.ckpt only if you want to resume training from the saved optimizer / scheduler state.

The model family

All six share the architecture, hyperparameters, and a fixed step budget of 12,396 optimizer steps; the only thing that varies between rows is the supervising label (or, for ink0, the training segments).

Citation

If you use this model in published work, please cite the Vesuvius Challenge and the underlying ResNet3D paper:

@inproceedings{hara2018can,
  title  = {Can spatiotemporal 3D CNNs retrace the history of 2D CNNs and ImageNet?},
  author = {Hara, Kensho and Kataoka, Hirokatsu and Satoh, Yutaka},
  booktitle = {CVPR}, year = {2018},
}

Licence

MIT.