Vasco Palmeirim Vector Maps - Production Flow ( Portugal - Portimão ) 1

Introduction SIGMAGEO is a Portuguese Private Company, that is the Photomod distributor for Portugal. We have also Production Departments which deal mainly in GIS and Mapping. 2 The purpose of this document is to give an example of the power of Photomod software, showing how SIGMAGEO uses PhotoMod in Map Production. The following case will show how Photomod modules helps you produce vector maps, while we present a flow chart of the production phases.

Work location (1) The working area is located about 24 Km West of Portimão, with an area of 482 ha 3

Work location (2) The area is a bit hilly, but without being rough. 4

Detailed specifications 5 Aerial Photographs  Maximum pixel size (terrain) 5 cm  File format : uncompressed TIFF, RGB 16 bit color pixel  60% image overlap inside strips  30% strip overlap Global 3D Vector file  Scale 1:500  File format : Autocad 2000 binary DWG  Planimetric Precision : 10 cm  Planimetric Details: Buildings, Road, Walls Slopes, Water lines, …  Contour lines every 0,5 meter Global Orthophotomap  Scale 1:500  File format : uncompressed JPEG  TFW georeference file  Pixel size : 10 cm  Planimetric Precision : 10 cm State certification  The vector maps and orthophotos must have a certificate from DIRECÇÃO GERAL DO TERRITÓRIO, the former INSTITUTO GEOGRÁFICO PORTUGUÊS.

Project Planing With these parameters set by the client, we planned our production line as follows: 6 1. Aerial photography 2. Ground Control Points (GPS) 3. Block orientation 4. Aerotriangulation with AT module 5. Block adjustment with Solver A module 6. Vector data acquisition with StereoDraw module 7. TIN editing with DTM module 8. Orthorectification with Mosaic and Geomosaic Final editing with CAD software

Aerial photographs IMU/GPS was used 7 The flight was done using ZI’s DMC camera: 4 Strips 107 images

Ground control points (1) Being an area with very few human contact, it was very difficult to choose planimetric details that could be used as good Ground Control Points (GCP). Especial care is always used in choosing points not near to trees and other objects that clouds satellite observations. We always try to choose GCP on ground level, so that is will be easier to observe in stereoscopic viewing. It also prevents human error in antenna height compensation. Good points are sidewalks, white paintings in the roads, sewer cover, etc… 8

Ground control points (2) 9 When ground detail made it difficult to choose good GCPs, points should subdivided in 2 neighboring points. During fieldwork, we used SOKKIA GPS GSS1 2 band receivers (static mode) recording satellite data every 10 seconds during a minimum of 20 minutes. Coordinates were calculated with post-processing software by Sokkia, thus achieving better than 1 cm precision. Even using IMU data, we measured 24 GCP to guarantee the precision of the technical specifications of the client.

Block / Orientation (1) Block forming was very easy using PhotoMod tools: Importing images

Block / Orientation (2) Block forming was very easy using PhotoMod tools: 11 2 – Editing camera parameters

Block / Orientation (3) Block forming was very easy using PhotoMod tools: 12 3 – Automatic interior orientation

Block / Orientation (4) Block forming was very easy using PhotoMod tools: Importing external orientation data file

Block / Orientation (5) Block forming was very easy using PhotoMod tools: 14 5 – Automatic Block Layout

Block / Orientation (6) Block forming was very easy using PhotoMod tools: 15 6 – Automatic Block Layout – without layout6 - Automatic Block Layout – by external orientation

Aerotriangulation (1) Aerotriangulation followed the usual sequence in PhotoMod AT module: Creating manual Strip Ties

Aerotriangulation (2) Aerotriangulation followed the usual sequence in PhotoMod AT module: Creating automatic Ties Points Because the area has many vegetation and few good planimetric details, we had to create manually 729 Strip and tie points, while automatically we only achieved 402 points. This means a ratio of 64/36% when we use to achieve ratios of 10/90%

Aerotriangulation (3) Aerotriangulation followed the usual sequence in PhotoMod AT module: Creating the Relative Orientation Report

Aerotriangulation (4) Aerotriangulation followed the usual sequence in PhotoMod AT module: 19 4 – Using the Relative Orientation Report

Aerotriangulation (5) Aerotriangulation followed the usual sequence in PhotoMod AT module: Editing points outside given parameters

Aerotriangulation (6) Aerotriangulation followed the usual sequence in PhotoMod AT module: 21 6 – Importing Ground Control Points data files

Aerotriangulation (7) Aerotriangulation followed the usual sequence in PhotoMod AT module: 22 7 – Measuring Ground Control Points

Block Adjustment (1) Block adjustment followed the usual sequence in PhotoMod Solver A module: 23 1 – Choosing parameters for adjustment

Block Adjustment (2) Block adjustment followed the usual sequence in PhotoMod Solver A module: 24 2 – Control using Free model option

Block Adjustment (3) Block adjustment followed the usual sequence in PhotoMod Solver A module: 25 3 – Making final adjustments

Block Adjustment (6) Block adjustment followed the usual sequence in PhotoMod Solver A module: 26 6 – Controlling GCP stereoscopic measurements

Data aquisition (1) Using PhotoMod´s StereoDraw module: 27 1 – Choosing/creating Codetable

Data aquisition (2) Using PhotoMod´s StereoDraw module: 28 2 – Vectorizing planimetric details, such as: Roads Buildings Walls Fences Posts Lakes Rivers Slopes Ridges Bridges etc...

Data aquisition/DTM (1) Using PhotoMod´s DTM module: 29 1 – From StereoDraw data, we now use 3D data which correctly defines earth surface, such as: Water lines, lakes, rivers, slopes, ridges, roads, paths … to make a first TIN 2 – Drawing extra lines and points 3 – Building contour lines with 0,5 m interval 4 – DEM building with 50 cm cell size

Orthorectification (1) Using PhotoMod´s Mosaic module: 30 1 – Choosing outside limit of all images

Orthorectification (2) Using PhotoMod´s Mosaic module: 31 2 – Choosing parameters for orthorectification: DEM

Orthorectification (3) Using PhotoMod´s Mosaic module: 32 3 – Choosing parameters for orthorectification: Cell size, background color, georeference file

Orthorectification (4) Using PhotoMod´s Mosaic module: 33 4 – Choosing parameters for orthorectification: Global adjustment

Orthorectification (5) Using PhotoMod´s Mosaic module: 34 5 – Choosing parameters for orthorectification: No spliting, choosing all images

Orthorectification (6) Using PhotoMod´s GeoMosaic module: 35 6 – Viewing all images after orthorectification

Orthorectification (7) Using PhotoMod´s GeoMosaic module: 36 7 – Choosing cutlines creation parameters

Orthorectification (8) Using PhotoMod´s GeoMosaic module: 37 8 – Editing cutlines

Orthorectification (9) Using PhotoMod´s Geomosaic module: 38 9 – Final sheet spliting, creating the final orthophotos with 10 cm cell size

Vector map Using CAD software,all planimetric and height data created were joined in only one drawing Topologic data control was made, buildings closed, contour labels added, etc…

Vector map and ortophoto (1) Controlling orthophoto and vector map 40

Vector map and ortophoto (2) Detailed close-up 41

Vector map and ortophoto (3) Another close-up 42

Flowchart 43 Aerial photography Ground Control Points Block orientation 1.Import images 2.Edit camera 3.Interior orientation 4.Import external orientation data 5.Automatic block layout Aerotriangulation 1.Manual Strip Ties 2.Automatic tie points 3.Creating and using Relative orientation report 4.Importing GCP data files 5.Measuring GCP Block adjustment 1.Choosing parameters 2.Using Free Model 3.Making final adjustments Vector data acquisition 1.Codetable 2.Vectorizing planimetric data DTM 1.Using 3D vectors on the terrain 2.Vectorizing extra lines and points 3.Creating final TIN 4.Building contour lines 5.DEM building Orthorectification (Mosaic) Making orthoimages off all images 6.(Geomosaic) Viewing the orthoimages 7.(Geomosaic) Creating cutlines 8.(Geomosaic) Editing cutlines 9.(Geomosaic) Generating final orthophotos with sheet spliting Final editing of vector data

Final Notes 44 The 5.1 and 5.2 Photomod versions we used in this presentation are very powerful tools for Map Production, even with very precise technical requests from our clients. I must remember, that this paper does not refer many other potential applications that Photomod software modules can do. I am proud to inform that personnally I have been working with Photomod software for the last 12 years, and wish to use this opportunity to congratulate Racurs and all their workers, for the excellent software development that they have been producing along these years.