Ruben JOYE - ruben.joye@hogent.be Lecturer University College Ghent (Faculty School of Arts)

THURSDAY, 31 MAY 2012 - 16U00 - TEACHING DIGITAL PLANNING METHODS

Generating a point cloud from a crowdsourced photographic survey

INTRODUCTION

L:N Landscape forum (source: le-notre.org)

INTRODUCTION

Antalya (Turkey) (source: lonelyplanet.com)

INTRODUCTION

Sillyon / Sillyum (source: Google Maps)

INTRODUCTION

Sillyon / Sillyum (source: Google Maps)

INTRODUCTION

[A] Lower gate [B] Ramp [C] Bastions [D] Tower[E] Late Building [F] Hellenistic building[G] Building with Pamphylian inscription [H] Cistern[J] Theatre[K] Odeum [L] Upper Gate[M] Houses[N] Temple [01] Unidentified Building[02] Temple[P] Stadium[Q] Palace [R] Necropolis[S] Waterworks [T] Round Tower

PLAN OF Sillyum (SOURCE: Bean G.E.)

INTRODUCTION

Sillyum seen from Asar Koyu (photo: Bean G.E.)

INTRODUCTION

Water source near lower gate (photo: Argyraspid)

INTRODUCTION

Theatre (photo: Argyraspid)

INTRODUCTION

3d scanned farm house (image: djaweb) (PHOTO: LEICA)

INTRODUCTION

test with a local chapel

URL: http://photosynth.net/view.aspx?cid=515b5e37-9d99-4395-afcf-93295c425056

INTRODUCTION

URL: http://photosynth.net/view.aspx?cid=515b5e37-9d99-4395-afcf-93295c425056

test with a local chapel

INTRODUCTION

Exported pointcloud edited in Autocad

INTRODUCTION

Le:Notre heritage group on the Sillyum site

PHOTOGRAPHIC SURVEY

ATTENTION POINTS:

• provide enough overlap between photos

• panorama first• don’t crop pictures• shoot wide angle pictures• limit the angle between

photos• move around the object• shoot scenes with lots of

detail and texture

(source: photosynth blog)

visual reference (image: Photosynth blog)

SITE 1: tower

FOTO 2:reutelbeekPHOTO 099

:

TOWER

FOTO 3:

Roeselarestraat

PhOTO 239TOWER

Photo 359

tower

PHOTOGRAPHIC SURVEY

PHOTOGRAPHIC SURVEY

SITE 2: palace area

PHOTO 290

PALACEPHOTO 059

PALACE

FOTO 3:Roeselarestraat

PhOTO 341PALACE

PHOTO 589PALACe

GENERATING THE POINT CLOUD USING PHOTOSYNTH

The easy to use interface of Photosynth

PHOTOSYNTH:

• download from photosynth.net

• requires Silverlight NET• requires a free Windows

Live account• reliable and fast broadband

connection is needed• reduce resolution size of

photos prior to process & upload

GENERATING THE POINT CLOUD USING PHOTOSYNTH

the tower in the Photosynth browser

URL: http://photosynth.net/view.aspx?cid=0c14a64b-d223-4bb0-9c35-89a9b5c55e45

GENERATING THE POINT CLOUD USING PHOTOSYNTH

the PALACE area in THE Photosynth browser

URL: http://photosynth.net/view.aspx?cid=188b2b00-eebc-4e01-86b1-1842cecd17bd

GENERATING THE POINT CLOUD USING PHOTOSYNTH

Presentation (Photo: Ida Fasching)

further analysis using Autocad

User interface of the browseps-plugin

BROWSEPS:

• free AutoCAD Plugin• requires NET Framework 3.5

SP1• command ‘browseps’• stores a *.pcg file locally

further analysis using Autocad

User interface of SynthExport tool

BROWSEPS:

• free export tool• requires NET Framework 3.5

SP1• support for *.obj, *.ply, *vrml,

and *.x3d

further analysis using Autocad

POINT CLOUD of the tower Classified by height

further analysis using Autocad

POINT CLOUD of the tower Classified by height

further analysis using Autocad

POINT CLOUD of the tower Classified by height

further analysis using Autocad

orthogonal view of the tower & topography

further analysis using Autocad

orthogonal view of both sides of the tower

further analysis using Autocad

POINT CLOUD of the palace Classified by height

further analysis using Autocad

TWO SECTIONS DERIVED FROM THE POINTCLOUD

CONCLUSIONS

PRO:

• doesn’t require expensive or heavy equipment

• easy to use• fast results

CON:

• far less accurate and detailed then a 3D laser scanner

• difficulties with repetitive patterns and complex occlusions

• Linux and Mac OS are unsupported

• Needs (fast) internet connection

Ruben JOYE - ruben.joye@hogent.be University College Ghent (Faculty School of Arts)