arXiv Computer Vision By Ehsan Agha Ebrahimi, Yong-Cheol Lee, Keith G. Mills

Domain Adaptation of SAM 2.1 for Building-Component Segmentation in Image-Based 3D Reconstruction

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The paper reports fine‑tuning the Segment Anything Model (SAM) 2.1 on the HBD dataset of 2,679 images from 42 buildings to improve multi‑class segmentation of 2D building images. The fine‑tuned model achieves a higher mean Intersection‑over‑Union (mIoU) of 69.6% compared to 49.9% for the pretrained version, and shows better performance on larger object classes. These enhanced 2D masks are then used in Group Anything with Radiance Fields (GARField) to group building components more accurately in 3D neural radiance fields, facilitating more precise 3D auto‑reconstruction of building structures.

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