Acquisition and integration of spatial and acoustic features: a worflow tailored to small-scale heritage architecture

Abstract

This paper reports on an interdisciplinary data acquisition and processing chain, the novelty of which is primarily to be found in a close integration of acoustic and spatial data. It provides a detailed description of the technological and methodological choices that were made in order to adapt to the particularities of the corpus studied (interiors of small scale rural architectural artefacts) keeping in mind the backbone objective of the research: facilitate comparisons (among buildings, among spatial and acoustic features). The research outputs pave the way for proportion-as-ratios analyses, as well as for the study of perceptual aspects from an acoustic point of view. Ultimately, “perceptual” acoustic data characterised by acoustic descriptors will be related to “objective” spatial data such as architectural metrics. The experiment is carried out on a set of fifteen “small-scale” rural chapels, which is a corpus intended at fostering cross-examinations in the context of an architectural programme acting as a constant. The specificity of this corpus, in terms of architectural layout, usage, and economic or access constraints, will be shown to have had a significant impact on choices made during the acquisition and processing chains.

Combined Web-Based Visualisation of 3D Point Clouds and Acoustic Descriptors: An Interdisciplinary Challenge

“…In such cases, an additional sub-menu opens in the right-hand part of the user interface when the tool is selected (Figure 3, right). An evaluation of the data quality and comparison with terrestrial laser scanning as reference (TLS) has been performed and is provided in [20]. Our results are consistent with previous works assessing the potential of fisheye and spherical photogrammetry for architectural interiors and narrow spaces.…”

“…This protocol also aims at improving accuracy: the lens axis is successively directed towards all coplanar surfaces (floor/ceiling, longitudinal/transversal walls) in order to optimise the unstitched images. An evaluation of the data quality and comparison with terrestrial laser scanning as reference (TLS) has been performed and is provided in [20]. Our results are consistent with previous works assessing the potential of fisheye and spherical photogrammetry for architectural interiors and narrow spaces.…”

“…This allows a qualitative (and rough) assessment of the reliability of the dimensional characteristic extracted from the integrator. The quality of the measurement is impacted by the user's picking, the granularity of the measurement allowed by the integrator (1cm), the differences in density and quality within a point cloud and between point clouds, but above all by factors related to the measurement itself and its post-processing, upstream of the integrator, a point commented in [20]. The 3D integrator displays previously oriented and scaled point clouds: it can therefore be used to directly extract the dimensional characteristics corresponding to the systematic dimensional analysis grid (on the three X,Y,Z axes).…”

“…The approach was developed in response to a specific set of constraints (small-scale architecture, remote sites, lightweight, low-cost solutions, reproducibility and reusability of outputs, etc.) that are detailed in [2]. It was applied to 15 rural chapels in south-eastern France, with an objective to support reproducibility (from acquisition to post-processing stages), as well as comparative analyses (see Supplementary Materials section for further details on the corpus).…”

“…The development of the prototype and the functions it is intended to perform are closely related to a specific, interdisciplinary survey protocol developed jointly by architects and acousticians. Detailed in [2], it combines existing techniques and can be summed up as follows:…”