Learning Grammars for Architecture-Specific Facade Parsing

International audienceParsing facade images requires optimal handcrafted grammar for a given class of buildings. Such a handcrafted grammar is often designed manually by experts. In this paper, we present a novel framework to learn a compact grammar from a set of ground-truth images. To this end, parse trees of ground-truth annotated images are obtained running existing inference algorithms with a simple, very general grammar. From these parse trees, repeated subtrees are sought and merged together to share derivations and produce a grammar with fewer rules. Furthermore, unsupervised clustering is performed on these rules, so that, rules corresponding to the same complex pattern are grouped together leading to a rich compact grammar. Experimental validation and comparison with the state-of-the-art grammar-based methods on four diff erent datasets show that the learned grammar helps in much faster convergence while producing equal or more accurate parsing results compared to handcrafted grammars as well as grammars learned by other methods. Besides, we release a new dataset of facade images from Paris following the Art-deco style and demonstrate the general applicability and extreme potential of the proposed framework

Unveiling the structure of the Marrakech Medina: Architecture History as a precedent for Contemporary Architectural Design

The population increase that occurred in North African and Middle-Eastern cities, has led to an uncontrolled urban growth that produced urban environments lacking the spatial richness from their historical vernacular towns. In order to alert and to change this context this paper illustrates work in progress for a design project at the city of Marrakech in Morocco. It describes from a historical and analytical point of view, research carried out at the Zaouiat Lakhdar quarter of the Marrakech Medina. The goal is to create the basis for a computational tool that could capture spatial features of the existing architectonic fabric and apply them at contemporary architectural scenarios. The methodology used is explained from the initial historical analysis and fieldwork realized in situ to the identification of social, religious and geometric set of laws and its codification into two different types of generative rules. These were than applied either at the urban level, or at the domestic level. At the urban scale the system generates options for new urban neighborhood layouts, and at the domestic level, proposes different housing typologies taking in consideration architectural precedents. Results from a class will be showed. The ultimate objective of this project is to illustrate how fruitful can be the interdisciplinary dialogue between history, culture, computation and architecture. It outcome is proved as a dynamic design process able to infer on the organization of a Design Studio, and in the formalization of a computational design methodology that contributes with architectural solutions to the building of the local environment

Detecting and Parsing Architecture at City Scale from Range Data

We present a method for detecting and parsing buildings from unorganized 3D point clouds into a compact, hierarchical representation that is useful for high-level tasks. The input is a set of range measurements that cover large-scale urban environment. The desired output is a set of parse trees, such that each tree represents a semantic decomposition of a building – the nodes are roof surfaces as well as volumetric parts inferred from the observable surfaces. We model the above problem using a simple and generic grammar and use an efficient dependency parsing algorithm to generate the desired semantic description. We show how to learn the parameters of this simple grammar in order to produce correct parses of complex structures. We are able to apply our model on large point clouds and parse an entire city

AnUrban Grammar for the Medina of Marrakech: Towards a Tool for Urban Design in Islamic Contexts

This paper describes research carried out to develop a parametric urban shape grammar for the Zaouiat Lakhdar quarter of the Medina of Marrakech, in Morocco. The goal is to create the basis for a system that could capture some features of the existing urban fabric and apply them in contemporary urban planning

Virtual Campus for the University of Jaume I, Castelló, Spain: 3D Modelling of the Campus Buildings using CityEngine

Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.The Virtual Smart Campus for the University of Jaume I – Visca Uji – is a project that aims to transform the University of Jaume I (UJi) into a “Smart Campus”. Several applications are part of the Smart Campus such as Uji Place Finder, Energy Consumption, Routes, Resources Management, and Indoor Mapping. Part of this project is the creation of the 3D model of the university buildings using Esri software — City Engine. This study analysed two 3D modeling approaches: procedural modeling language (CGA Shape) and manual modeling. The first, Computer Generated Architecture (CGA) shape is an extension of set grammars that have been applied in CG successfully over the years. And the second, CityEngine offers a set of shape creation and editing tools that allows a more intuitive and pragmatic 3D modeling technique. Both approaches have advantages and disadvantages, overall creating a 3D model by using procedural modelling language showed to be the more efficient and pragmatic method