Esri Image Server:Making Scanned Maps Accessible

Aileen Buckley

Outline

• Why- There are lots of scanned maps and they have many uses

• How- Scan

- Structure

- Create Mosaic datasets

- Publish as Image Service

- Use in WebMaps

Scanned Maps

• Typically maps created from mapping agencies- Topographic maps

- Historic scanned maps

- Navigation maps

Uses of scanned map collections

• Authoritative information source

• Record for land resource management- Forest plot perimeters

- Wetlands

- Agriculture

- Glaciers

- Land/water boundaries

- Political boundaries

• Historical analysis

• Navigation

• Adventure/exploration

How to get the data?

• Some can be downloaded- Eg from USGS

- Formats- TIFF, SID

- Compressed, Uncompressed

- 1-bit, 8-bit, color map

- Georeferenced?

• Scan- Flat bend / Large Format

- RGB, Pan

- 300-600dpi (best to test)

-

Management Considerations

• Archive the Raw (uncompressed scans)

• Store as- TIF with JPEG compression

- RGB compression (not YCbCr)

- Test Q values, depend on content (typically about Q80)

- Create Pyramids

- Use ArcGIS CopyRaster (or FWTools)

- Can use other formats- But compressed TIF is fast, and good and open

Georeferencing

• Use the ArcGIS Georeference tool

• Ensure appropriate projection and datum are set- Set TIF file as “read only”

• Use Update Georeferencing (not Rectify)- Set as Projective, or 2nd Order

- Will create associated AUX.XML

• Multiple methods to help automate

• For large volumes consider QuadG

• Do not reproject or rectify

• Do not clip borders/legends

Scanned map example

Scanned map example

What you want see

Scanned map example

What you want hidden

But not always – there is valuable info here!

How to Manage collections & Metadata

• Individual scans can be added directly to ArcGIS- Will perform required reprojection

• Use Mosaic Datasets for collections of scanned maps

What is a mosaic dataset?

• A geodatabase data model used to catalog, process, visualize and share your collections of raster, imagery, and lidar data

• Indirect data management- Points to the data

- Contains metadata

• Unlimited size

• Provides dynamic mosaicking

• & on-the-fly processing

• Used as a catalog and an image

• Served as an image service

Simple way to make a mosaic dataset

• Create FileGeodatabase

• Create Mosaic Dataset

• Add Rasters – Point to folders that contain the scanned maps

• Edit footprints

• Add attributes

• Build overviews

• Modify properties

CreateMosaic Dataset

Click icon to insert Picture

Demo

Automation – Further simplifies the process

• On the ArcGIS Resource Center

• Example of how to automate and simplify the process

• A toolbox and scripts (MDCS)

• 6 tool & 80 parameters

• Customizable

Publishing the mosaic dataset as an image service

• Used for analysis and as background

• Best quality – On-the-fly processing

• Most functionality – Dynamic mosaicking

• Optionally Register with ArcGIS Online

• Use in web maps and apps

• Query the collection (catalog)

• Can enable Export and Download

Publishing as an Cached Map Service

• Creates Static Background

• Loose functionality

• Simple background

• In ArcGIS for Desktop- Cache

- Package

- Upload

• In ArcGIS Online- Publish & Share