vasco palmeirim vector maps - production flow ( portugal - portimão - 2012 ) 1

Vasco Palmeirim

Vector Maps - Production Flow

( Portugal - Portimão - 2012 )

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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 .

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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

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Work location (2)

The area is a bit hilly, but without being rough.

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Detailed specifications

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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 PlaningWith these parameters set by the client, we planned our production line as follows:

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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

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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…

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Ground control points (2)

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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:

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1 - Importing images



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2 – Editing camera parameters



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3 – Automatic interior orientation



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4 - Importing external orientation data file



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5 – Automatic Block Layout



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6 – Automatic Block Layout – without layout6 - Automatic Block Layout – by external orientation

Aerotriangulation (1)

Aerotriangulation followed the usual sequence in PhotoMod AT module:

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1 - Creating manual Strip Ties



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2 - 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%



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3 - Creating the Relative Orientation Report



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4 – Using the Relative Orientation Report



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5 - Editing points outside given parameters



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6 – Importing Ground Control Points data files



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7 – Measuring Ground Control Points

Block Adjustment (1)

Block adjustment followed the usual sequence in PhotoMod Solver A module:

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1 – Choosing parameters for adjustment



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2 – Control using Free model option



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3 – Making final adjustments



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6 – Controlling GCP stereoscopic measurements

Data aquisition (1)

Using PhotoMod´s StereoDraw module:

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1 – Choosing/creating Codetable

Data aquisition (2)

Using PhotoMod´s StereoDraw module:

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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:

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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:

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1 – Choosing outside limit of all images



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2 – Choosing parameters for orthorectification: DEM



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3 – Choosing parameters for orthorectification: Cell size, background color, georeference file



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4 – Choosing parameters for orthorectification: Global adjustment



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5 – Choosing parameters for orthorectification: No spliting, choosing all images


Using PhotoMod´s GeoMosaic module:

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6 – Viewing all images after orthorectification



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7 – Choosing cutlines creation parameters



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8 – Editing cutlines


Using PhotoMod´s Geomosaic module:

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9 – Final sheet spliting, creating the final orthophotos with 10 cm cell size

Vector mapUsing CAD software ,all planimetric and height data created were joined in only one drawing

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1 - Topologic data control was made, buildings closed, contour labels added, etc…

Vector map and ortophoto(1)

Controlling orthophoto and vector map

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Detailed close-up

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Another close-up

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Flowchart

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Aerial photographyGround Control Points

Block orientation 1. Import images2. Edit camera3. Interior orientation4. Import external orientation data5. Automatic block layout

Aerotriangulation 1. Manual Strip Ties2. Automatic tie points3. Creating and using Relative orientation report4. Importing GCP data files5. Measuring GCP

Block adjustment 1. Choosing parameters2. Using Free Model3. Making final adjustments

Vector data acquisition 1. Codetable 2. Vectorizing planimetric data

DTM 1. Using 3D vectors on the terrain2. Vectorizing extra lines and points3. Creating final TIN4. Building contour lines5. DEM building

Orthorectification 1 - 5 (Mosaic) Making orthoimages off all images6. (Geomosaic) Viewing the orthoimages7. (Geomosaic) Creating cutlines8. (Geomosaic) Editing cutlines9. (Geomosaic) Generating final orthophotos with sheet spliting

Final editing of vector data

Final Notes

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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.

vasco palmeirim vector maps - production flow ( portugal - portimão - 2012 ) 1

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