96332 - FOTOGRAMMETRIA PER L'ARCHITETTURA CON LABORATORIO

Academic Year 2021/2022

  • Docente: Marco Gaiani
  • Credits: 8
  • SSD: ICAR/17
  • Language: Italian
  • Teaching Mode: Traditional lectures
  • Campus: Bologna
  • Corso: Single cycle degree programme (LMCU) in Architecture and Building Engineering (cod. 0940)

Learning outcomes

At the end of the course, the student has both theoretical and practical skills related to the architectural photogrammetry techniques and the construction of three-dimensional digital models starting from photogrammetric techniques in the fields of architecture and historical conservation of monuments. In particular, the student will be able to: design a photogrammetric survey, to do it, to build reality-based 3D models, to prepare them for the typical uses of design processes: analysis, design, management, communication.

Course contents

PHOTOGRAPHY USING SMARTPHONE CAMERAS
-Description of photographic equipment and operating principles
-Exemplification of the use of cameras and lighting bodies, shooting of simple objects
-Geometric deformation and perspective in photography
-Noise and denoise
-Photographic shooting aimed at the survey

GEOMETRIC MODELING
-Homogeneous coordinates and geometric transformations
-Main modeling methodologies
-Polygonal graphic formats (OBJ, PLY, STL, etc.)
-Solid modeling and Boolean operations
-CSG
-B-Rep modeling
- Point clouds and their conversion into triangular meshes
-Mesh of triangles for the representation and reconstruction of surfaces
-Mesh processing: simplification, smoothing and regularization

COLORIMETRY
-CIE 1931 diagram and Grossmann's law
-Color models: RGB and HSV
-Color spaces
-Color acquisition and reproduction
-Color appearence and BRDF
-Color measurement
-Use of color systems (Munsell, NCS, Pantone, RAL)
-Colorimeters and spectrophotometers
-Color acquisition through imaging techniques
-Color correction techniques
-White and color balance in images
-Color targets
-Color management
-Error evaluation metrics in color measurement
-SHAFT-based color correction

TEXTURE MAPPING TECHNIQUES
-Texture mapping
-Bump Mapping
-Normal Mapping
-Displacement mapping

ELEMENTS OF PHOTOGRAMMETRY AND AUTOMATIC PHOTOGRAMMETRY
-Basic concepts
-Sensors
-Planning of a photogrammetric survey
-Collinearity
-Camera models and camera calibration
-Room orientation
-Reconstruction of the object from one, two or more images
-Manual, semi-automatic, automatic procedures
-Image Feature Detection and Matching
-RANSAC
-Structure from Motion
-Bundle adjustment
-Sparse clouds of points
-Dense Stereo Matching
- Scaling
-General rules of shooting and camera network for SFM photoreconstruction for architecture
-Pre-processing of images
-Photogrammetric texturing
-Creation of orthophotos
-Extraction of technical papers
-Examples

Readings/Bibliography

Required

On-line handouts on: https://virtuale.unibo.it/

Optional

-De Luca L., La fotomodellazione architettonica, Dario Flaccovio Editore, Palermo, 2011.

-Docci M., Maestri D., Gaiani M., Scienza del disegno, Città Studi, Novara, 2021.

-Guidi G., Russo M., Beraldin J.A., Acquisizione 3D e modellazione poligonale, Mac Graw Hill, Milano, 2010.

-Luhmann T., Robson S., Kyle S, Boehm J., Close-range photogrammetry and 3D imaging, 3rd edition, De Gruyter, Berlino, 2020.

-Szelisky R., Computer Vision: Algorithms and Applications, Springer, Berlino, 2011

-Hunt R.G.W., The Reproduction of Colour, 6th edition, Wiley, Hoboken, 2005.

Teaching methods

The course is organized in cycles of lectures, a series of practical exercises in the laboratory to learn specific software and the application of the theoretical and practical contents to a case study.

The course is therefore a practical laboratory in which to apply knowledge on photogrammetric survey and develop the resulting documents.

The annual exercise has as goal the construction of a metrically faithful and colorimetrically correct 3D model of a monumental artefact or of its parts for the purposes of the following historical / constructive analysis, conservation and / or restoration and communication, i.e. capable of supporting all operations relating to the lifecycle of the monument. The 'annual exercise' must be processed continuously and periodically checked.

A presentation in .pptx, .key or .pdf format, RAW images and models processed in .ply format must be delivered on the day of the exam.

In addition to the annual exercise, ex-tempore exercises are provided with content strictly related to the lessons.

Assessment methods

Learning assessment takes place through the oral exam, which ascertains the acquisition of all the knowledge and skills expected by a discussion on the works produced during the year.

The preparation and presentation of the exercise work is a necessary condition for admission to the exam: the completeness of the documentation will be verified at the end of the course in a "final review" required for registration for the exam.

Teaching tools

The student will have a PC available in the PC classroom during the scheduled academic calendar days. It is advisable to have a laptop on which it is possible to install the listed open-source software.

For the photos you will use your smartphone.

Office hours

See the website of Marco Gaiani