arXiv Computer Vision

Initialization and Stopping Tolerance in CPU Dermoscopic Segmentation

The study investigates how contour initialization and stopping tolerance jointly influence active‑contour segmentation performance on dermoscopic images. Using scikit‑image’s Chan‑Vese implementation on a resized ISIC 2017 dataset, the authors compare Otsu, checkerboard, disk, and Otsu‑initialized contours under default and tighter level‑set tolerances. Results show that Otsu initialization improves mean Dice scores at default tolerance but the advantage diminishes with tighter tolerance, and that evaluation metrics can vary across lesion size strata, underscoring the need to report initial fields, tolerances, and iteration counts.

arXiv Machine Learning
Sep 14

Beyond Accuracy: Uncertainty-Guided Boundary Refinement for Reliable Biomedical Image Segmentation

The paper introduces RABR-Net, a two‑stage framework that refines biomedical image segmentation boundaries by combining multiple uncertainty measures into a boundary‑aware representation. A gated residual refiner uses this representation to selectively correct uncertain boundary pixels while preserving confident regions, leading to modest but statistically significant improvements in Dice, Boundary Dice, and HD95 metrics on a held‑out test set. Qualitative results show the refiner focuses on uncertain cytoplasm and nucleus boundaries, though calibration does not automatically improve.

By Anima Kujur
arXiv Machine Learning
4d ago

Less Is More: A Leakage-Controlled Study of Dermoscopic Preprocessing for Joint Skin Lesion Classification and Segmentation with YOLO26

arXiv:2610.08570v1 Announce Type: new Abstract: Handcrafted preprocessing is widely employed in automated dermoscopic analysis to suppress imaging artifacts and enhance lesion visibility. Nevertheles...

By Truong Viet Vu, Nguyen Chi Hai, Nguyen Phuc Nguyen, Ngo Hoang Tu, Vo Nguyen Quoc Bao, Nguyen Thai Anh
arXiv Computer Vision
Sep 17

STRADAViT: Self-Supervised Domain Adaptation of Vision Transformer Backbones for Radio Astronomy

STRADAViT is a self‑supervised continued‑pretraining framework that adapts Vision Transformer (ViT) backbones for radio‑astronomy image analysis. It curates mixed‑survey data, generates radio‑astronomy‑aware training views, and initializes encoders with ViT‑MAE, optionally adding register tokens. Evaluations on three morphology benchmarks (MiraBest, LoTSS DR2, and Radio Galaxy Zoo) show that a register‑based two‑stage checkpoint improves linear‑probe Macro‑F1 scores over the ViT‑MAE baseline and enhances fine‑tuning on MiraBest and RGZ DR1, though performance on LoTSS DR2 fine‑tuning declines; these differences are statistically significant.

By Andrea DeMarco, Ian Fenech Conti, Hayley Camilleri, Ardiana Bushi, Simone Riggi
arXiv Machine Learning
Sep 21

Detection is solved, delineation is not: what governs tooth segmentation on panoramic radiographs

The study evaluates automatic tooth segmentation on panoramic radiographs using a large annotated corpus of 1,422 images and 42,142 tooth polygons. It finds that increasing input resolution improves boundary precision (mask mAP50‑95 rises from 0.656 to 0.717) while detection performance remains unchanged, and that architectural changes have minimal impact on in‑domain accuracy. Targeted interventions such as LoRA adaptation, promptable foundation models, and anatomical label assignment provide negligible gains, indicating that resolution and acquisition diversity should be prioritized over model novelty.

By Muhammad Rehan, Moaz Amjad, Syed Danial Ahmed, Mariam Adnan, Haider Ali
arXiv Computer Vision
Sep 23

Observer Choice and Threshold Selection in Retinal Vessel Segmentation: A Subject-Separated Evaluation

The study investigates how the choice of annotation used to set a segmentation threshold influences retinal vessel segmentation performance. Using all 28 CHASE DB1 images and two human observers, the authors fit random forests and Extra Trees models, then compare five threshold policies—including fixed, observer‑tuned, mean‑observer, and maximin tuning—on the same score maps. Results show that maximin tuning alters thresholds in most fits but yields negligible changes in worst‑observer Dice scores, suggesting no accuracy advantage in this cohort.

By Wenhao Xu, Yixian Kong, Ting Pan, Changwei Wang, Feilong Wang, Rongtao Xu
arXiv Computer Vision
Sep 4

Exemplar: Classical Priors Complement Frozen Features for Few-Shot Microscopy Segmentation at Native Resolution

Exemplar is a few‑shot segmentation method that combines a frozen DINOv3 backbone with a fixed bank of classical native‑resolution filter responses in a single lightweight head. Trained only from support masks, it achieves a mean foreground intersection‑over‑union of 0.782 across eleven biomedical imaging datasets, outperforming either component alone and surpassing five other few‑shot methods in 54 of 55 comparisons. With a single annotated mask, Exemplar reaches 0.703, higher than a from‑scratch nnU‑Net trained on the same mask, and while nnU‑Net eventually overtakes it with eight masks, it requires 16–77× longer to fit.

By Michal Pr\r{u}\v{s}ek, Adam Novoz\'amsk\'y, Filip \v{S}roubek