3D Holoscopic Imaging for Cultural Heritage Digitalisation

The growing interest in archaeology has enabled the discovery of an immense number of cultural heritage assets and historical sites. Hence, preservation of CH through digitalisation is becoming a primordial requirement for many countries as a part of national cultural programs. However, CH digitalisation is still posing serious challenges such as cost and time-consumption. In this manuscript, 3D holoscopic (H3D) technology is applied to capture small sized CH assets. The H3D camera utilises micro lens array within a single aperture lens and typical 2D sensor to acquire 3D information. This technology allows 3D autostereoscopic visualisation with full motion parallax if convenient Microlens Array (MLA)is used on the display side. Experimental works have shown easiness and simplicity of H3D acquisition compared to existing technologies. In fact, H3D capture process took an equal time of shooting a standard 2D image. These advantages qualify H3D technology to be cost effective and time-saving technology for cultural heritage 3D digitisation

3D Holoscopic Imaging for Cultural Heritage Digitalisation

The growing interest in archaeology has enabled the discovery of an immense number of cultural heritage assets and historical sites. Hence, preservation of CH through digitalisation is becoming a primordial requirement for many countries as a part of national cultural programs. However, CH digitalisation is still posing serious challenges such as cost and time-consumption. In this manuscript, 3D holoscopic (H3D) technology is applied to capture small sized CH assets. The H3D camera utilises micro lens array within a single aperture lens and typical 2D sensor to acquire 3D information. This technology allows 3D autostereoscopic visualisation with full motion parallax if convenient Microlens Array (MLA) is used on the display side. Experimental works have shown easiness and simplicity of H3D acquisition compared to existing technologies. In fact, H3D capture process took an equal time of shooting a standard 2D image. These advantages qualify H3D technology to be cost effective and time-saving technology for cultural heritage 3D digitisation

TwinTex: Geometry-aware Texture Generation for Abstracted 3D Architectural Models

Coarse architectural models are often generated at scales ranging from individual buildings to scenes for downstream applications such as Digital Twin City, Metaverse, LODs, etc. Such piece-wise planar models can be abstracted as twins from 3D dense reconstructions. However, these models typically lack realistic texture relative to the real building or scene, making them unsuitable for vivid display or direct reference. In this paper, we present TwinTex, the first automatic texture mapping framework to generate a photo-realistic texture for a piece-wise planar proxy. Our method addresses most challenges occurring in such twin texture generation. Specifically, for each primitive plane, we first select a small set of photos with greedy heuristics considering photometric quality, perspective quality and facade texture completeness. Then, different levels of line features (LoLs) are extracted from the set of selected photos to generate guidance for later steps. With LoLs, we employ optimization algorithms to align texture with geometry from local to global. Finally, we fine-tune a diffusion model with a multi-mask initialization component and a new dataset to inpaint the missing region. Experimental results on many buildings, indoor scenes and man-made objects of varying complexity demonstrate the generalization ability of our algorithm. Our approach surpasses state-of-the-art texture mapping methods in terms of high-fidelity quality and reaches a human-expert production level with much less effort. Project page: https://vcc.tech/research/2023/TwinTex.Comment: Accepted to SIGGRAPH ASIA 202

Generation Of An Accurate, Metric Spatial Database Of A Large Multi Storied Building

This thesis presents the development of a novel method to generate an accurate, metric spatial database of a large multi storied building during construction. The algorithm uses the 3D CAD model of the building and the video of the structure captured by an Unmanned Aircraft System (UAS). The spatial database is then used to perform several inspection procedures such as, metric data analysis, spatial query for images, visualization through 3D textured model. The video is processed using a simultaneous localization and mapping (SLAM) system. SLAM generates a sparse 3D map of the environment. Our algorithm registers the 3D map with the 3D CAD model to generate the accurate metric spatial database. The user can click on the desired part of the CAD model for inspection and the image of that part will be shown by using the spatial indexing between the CAD model and the spatially distributed images. The image returned by the spatial query can be used to extract metric information. The spatial database is also used to generate a 3D textured model which provides a visual as-built documentation. The metric data calculation and textured model reconstruction methods have been compared to the state of the art Pix4D software (Latest Release (Version 3.1)). The proposed method has a mean squared error (MSE) of 31.9 cm2 and standard deviation of 4.28 cm where Pix4D had a higher MSE of 45.6 cm2 and standard deviation of 4.91 cm. Using statistical t-test and ANOVA tests we have shown that we are statistically 99% confident that the proposed algorithm has performed better than Pix4D