3. Producción
Browse
3 results
Search Results
- Some of the metrics are blocked by yourconsent settings
Item type:Publication, Practical method for measuring and characterizing reflective convex surfaces using Ronchi deflectometry(Optica Publishing Group, 2026-01-01)This paper presents the experimental implementation of a measurement system for convex optical surfaces based on Ronchi deflectometry. The experimental setup, data processing procedures, system calibration, and surface curvature parameters are described using primary information obtained from the deflectometric measurements, namely the ray slope at different heights or slope-position pairs. Finally, the proposed method was applied to characterize six samples distributed across the effective measurement range of the system. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, A 3D Assessment Tool for Precise Recording of Ceramic Fragments Using Image Processing and Computational Geometry Tools(2025-10-01)Recording ceramic fragments is essential for archaeological interpretation and conservation. When done manually, this task is very time consuming and greatly depends on the experience and skill of the archaeologist in charge. In this paper, we propose the implementation of a 3D acquisition and processing method to improve the accuracy and precision of the recording procedure. During the first step of the proposed process, 3D mesh models of ceramicfragments are obtained using a laser scanner. Subsequently, discrete 3D dynamic contour is utilised to extract points from the fragment's run. Orientation and diameter of the complete vessel are then estimated using a non-linear least square approach. Experiments, using manual techniques, report precision errors (variability) less than 11.97% in the diameter and 3.75% in inclination, whereas the 3D method reports errors of 2.07% and 0.42% for the same measures. Moreover, accuracy experiments report accuracy errors of less than 4.78% in the diameter, and 4.30% in inclination. These results suggest that the 3D method is accurate and more precise and i3.3%faster than the traditional methodology.4 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Enhanced Underwater 3-D Reconstruction: Case Study at Los Organos Reef Using 3dFeatureUp and 3dVisualAppUp(Institute of Electrical and Electronics Engineers Inc., 2026)In recent years, photogrammetry for tridimensional (3-D) reconstruction of underwater environments has gained significant interest, offering a nonintrusive approach to study and monitor aquatic ecosystems. However, underwater photogrammetry requires specialized equipment capable of capturing high-resolution images with adequate and uniform lighting. This article introduces two innovative methodologies, 3-D reconstruction based on Feature Enhancement (3dFeatureUp) and 3-D reconstruction based on Visual Appearance Enhancement (3dVisualAppUp), which are designed to enhance the accuracy and visual quality of 3-D underwater models. These methodologies incorporate novel algorithms for water image enhancement (WaterImgEnh) and water image restoration (WaterImgRest), aiming to address the challenges posed by underwater image acquisition such as light attenuation, color distortion, and visibility reduction. This approach is validated through the 3-D reconstruction of Los Organos Reef, located in Piura, Peru, employing a combination of standard and specialized underwater cameras along with a customized lighting system. The results demonstrate significant improvements in both the structural characteristics and visual appearance of the 3-D models, as compared to those generated by traditional methods or using specialized underwater cameras alone. The 3dFeatureUp method significantly enhances the structural features of the model by merging images from multiple cameras, while the 3dVisualAppUp methodology improves the visual quality of the models by correcting color imbalances and removing water effects.