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GIS and Geologic Mapping Day 2. Tools and methods to get started using GIS geologic mapping USGS Astrogeology. Introduction. Goals Data Models Projections Simple Lon, Lat Display Data Registration Loading Data Querying and Spatial Statistics. Some important notes (cont’d).

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gis and geologic mapping day 2

GIS and Geologic MappingDay 2

Tools and methods to get started using GIS geologic mapping

USGS Astrogeology

GIS for Planetary Geologic Mappers

introduction
Introduction
  • Goals
    • Data Models
    • Projections
    • Simple Lon, Lat Display
    • Data Registration
    • Loading Data
    • Querying and Spatial Statistics

GIS for Planetary Geologic Mappers

some important notes cont d
Some important notes (cont’d)
  • Though this presentation is geared toward geologic mappers, the information is relevant to all GIS users
  • Screen-shots are likely to differ from individual views
  • GIS skills are developed through software interaction … be patient and try new things!

 Tip icon will point out helpful hints throughout the presentation

GIS for Planetary Geologic Mappers

gis support
GIS Support
  • ESRI online portal to technical information
    • http://support.esri.com
  • ESRI ArcScripts
    • http://arcscripts.esri.com/
  • ESRI Educational Services
    • Instructor-led training
    • Virtual Campus courses
    • Web workshops
  • Books

GIS for Planetary Geologic Mappers

gis support nodes
GIS Support Nodes
  • Planet-specific information (e.g., data, discussion, tutorials)
    • http://webgis.wr.usgs.gov/
  • USGS discussion board (login required)
    • http://isis.astrogeology.usgs.gov/ … navigate to “Support”  “Planetary GIS Discussions”

“Plugging keywords into a internet search engine is a great way to search for GIS-related assistance!”

GIS for Planetary Geologic Mappers

transition
Transition
  • Data models – quick overview

GIS for Planetary Geologic Mappers

geographic data models

3

43

12

3

45

(v1,v2)

15

40

2

15

24

V

21

3

5

10

64

Geographic Data Models
  • Vector and Raster - two main families
  • Representation of geographic information:
    • Raster: location controlled, attribute measured
      • values are stored in ordered array, so that position in the array defines geographic location
    • Vector: attribute controlled, location measured
      • geographic coordinates are stored separately from attributes, connected with Identifiers

GIS for Planetary Geologic Mappers

rasters and vectors

Flat File

Vector-based line

4753456 623412

4753436 623424

4753462 623478

4753432 623482

4753405 623429

4753401 623508

4753462 623555

4753398 623634

Raster-based line

Flat File

0000000000000000

0001100000100000

1010100001010000

1100100001010000

0000100010001000

0000100010000100

0001000100000010

0010000100000001

0111001000000001

0000111000000000

0000000000000000

Rasters and Vectors

GIS for Planetary Geologic Mappers

rasters
Rasters
  • Each cell can be owned by only one feature.
  • Rasters are easy to understand, easy to read and write, and easy to draw on the screen. A grid or raster maps directly onto an array.
  • Grids are poor at representing points, lines and areas, but good at surfaces.
  • Grids are a natural representation for scanned or remotely sensed data.
  • Grids suffer from the mixed pixel problem.

GIS for Planetary Geologic Mappers

the mixed pixel problem
The mixed pixel problem

GIS for Planetary Geologic Mappers

methods of grid encoding
Methods of Grid Encoding
  • point-based
    • center point (regular grid) -DEMs, - but what if periodicity in landscape?; what if pop. density?
    • systematic unaligned (random in a cell)
  • area-based(have to integrate info...)
    • extreme value (max or min)
    • total (sum, like reflected light)
    • predominant type (most common)
    • presence/absence (binary result)
    • percent cover (% covered by single category)
    • precedence of types (highest ranking)

GIS for Planetary Geologic Mappers

slide12

Discrete (categorical)

Legend

Mixed conifer

Douglas fir

Oak savannah

Grassland

Raster representation. Each color represents a different value of a nominal-scale field denoting land cover class.

GIS for Planetary Geologic Mappers

slide13
Next  Projections

GIS for Planetary Geologic Mappers

map projections
Map projections
  • Define the spatial relationship between locations on earth and their relative locations on a flat map
  • Are mathematical expressions
  • Cause the distortion of one or more map properties (scale, distance, direction, shape)

GIS for Planetary Geologic Mappers

slide15

Map projections

A map projection is a set of rules for transforming features from the three-dimensional earth onto a two-dimensional display. No flat representation of the earth can be completely accurate, so many different projections have been developed, each suited to a particular purpose. Map projections differ in the way they handle four properties:

Area, Angles, Distance and Direction.

Rules:

  • No projection can preserve all four simultaneously, although some combinations can be preserved, such asArea and Direction
  • No projection can preserve both Areaand Angles, however. The map-maker

must decide which property is most important and choose a projection based on that.

GIS for Planetary Geologic Mappers

slide16

Map projections

GIS for Planetary Geologic Mappers

slide17

Different Plane Locations and Viewpoints

Normal or Polar

Oblique

Transverse orEquatorial

GIS for Planetary Geologic Mappers

different families of projections
Different families of projections

azimuthal

conic

cylindrical

GIS for Planetary Geologic Mappers

slide19

Classification of map projections

  • Conformal – local shapes are preserved
  • Equal-Area – areas are preserved
  • Equidistant – distance from a single location to all other locations are preserved
  • Azimuthal – directions from a single location to all other locations are preserved

GIS for Planetary Geologic Mappers

standard projections
Standard projections
  • Standard projections in planetary
    • Simple Cylindrical (Equidistance Cylindrical, Equirectangular)
      • rectangular global (decimal degrees or meters), simple “database” projection.
    • Sinusoidal
      • Used for global and many tiled data releases, equal area projection.
    • Mercator
      • Conformal, only use for equatorial areas, used in the Mars 1:5M series.
    • Transverse Mercator
      • Good for local areas “large” scale maps. A Small scale map shows more land area, but with smaller representations and, therefore, lesser detail.

GIS for Planetary Geologic Mappers

standard projections cont d
Standard projections – cont’d
  • Standard projections in planetary
    • Polar Stereographic
      • Good for polar, error increases away from central latitude (usually 90 or -90). Scale should be based on polar radius, can use polar radius.
    • Lambert Conformal
      • Good for mid latitudes. Error increases away from both standard parallels.
    • Orthographic
      • Globe view, not good for mapping as the limb falls away, makes for pretty figures but you need 3 globes to portray an entire planet. ISIS uses a spherical equation
    • Mollweide
      • Coming of age projection, global

GIS for Planetary Geologic Mappers

standard projections cont d1
Standard projections – cont’d
  • Other projections in planetary
    • Lambert Azimuthal
      • Good for mid latitude and polar, equal area, VICAR/HRSC team uses it for polar areas.
    • Robinson
      • Good for figures (similar to Mollweide)

GIS for Planetary Geologic Mappers

geographic geocentric issues
Geographic – Geocentric Issues
  • Planetographic vs Planetocentric - issues
    • Mars is basically the only problem
    • Most commercial commonly don’t use ocentric - ArcMap can.
    • Work around … use sphere definition for Mars.
    • For commercial applications, don’t use elliptical definitions and ocentric latitudes. Using elliptical and ographic is okay.

GIS for Planetary Geologic Mappers

east west longitude
East-West Longitude
  • Positive East vs. Positive West
    • Not much to say because commercial GIS/RS systems use positive East. You should always save your files using positive East.
    • To use West, you either fake out the system (by using your own code) or you switch software. It is just a shift, so no errors are incurred.
    • Luckily, if you are working in meters there is no East/West system, only Cartesian (X,Y).

GIS for Planetary Geologic Mappers

setting projections in arc
Setting Projections in Arc
  • Use toolbox under ArcCatalog to set dataset’s projection
    • Toolbox:
    • ArcCatalog (data properties)

To set many files, under toolbox samples – use batch define projection

GIS for Planetary Geologic Mappers

setting projections in arc1
Setting Projections in Arc
  • Setting planetary bodies in ArcMap
    • Example for decimal degree (lat/lon)
    • Okay to set ”Mars 2000.prj” ellipse. (find under “Coordinate Systems\Geographic Coordinate Systems\Solar System\Mars 2000.prj”) (semi-major radius 3396190 m)

GIS for Planetary Geologic Mappers

slide27

Setting Projections in Arc

  • Example for the ArcMap dataframe or for MOLA and most raster datasets on the data DVD.
  • To define a new projection click on New, “Projected”

GIS for Planetary Geologic Mappers

slide28

Setting Projections in Arc

  • Mars Polar projection
    • Note the “D_Mars_2000_Sphere_Polar” definition (semi-minor radius 3376200.0 m )

GIS for Planetary Geologic Mappers

slide29

Setting Projections in Arc

  • Projecting datasets using toolbox

Projecting vector

Projecting raster datasets

GIS for Planetary Geologic Mappers

display lon lat table
Display Lon, Lat Table
  • Create comma delimited text file (MSL.csv)

Name, Lat, Lon

Eberswalde, -23.86, 326.73

Holden, -26.37, 325.10

Gale, -4.49, 137.42

Mawrth, 24.65, 340.09

Nili Fossae, 21.01, 74.45

GIS for Planetary Geologic Mappers

load table
Load Table

1.

2.

GIS for Planetary Geologic Mappers

display x y data lat lon

2.

Display X,Y Data (lat,lon)

Right click table

3.

1.

4.

GIS for Planetary Geologic Mappers

save to permanent
Save to Permanent

Right click points

GIS for Planetary Geologic Mappers

landing site error ellipse
Landing Site Error “Ellipse”

Open Toolbox

Add Data if needed

GIS for Planetary Geologic Mappers

transition1
Transition
  • Simple Image Registration

GIS for Planetary Geologic Mappers

worldfile

*

Worldfile
  • Most simple image registration

5.0 (size of pixel in x direction) – A

0.0 (rotation term for row) - D

0.0 (rotation term for column) - B

-5.0 (size of pixel in y direction) - E

492169.690 (x coordinate of center of upper left pixel in map units) - C

54523.3180 (y coordinate of center of upper left pixel in map units) - F

GIS for Planetary Geologic Mappers

worldfile1
Worldfile
  • Algebraic Form (six parameter affine transformation)

x’ = Ax + By + C

y’ = Dx + Ey + F

where

x’ = calculated x-coordinate of the pixel on the map

y’ = calculated y-coordinate of the pixel on the map

x = column number of a pixel in the image

y = row number of a pixel in the image

A = x-scale; dimension of a pixel in map units in x direction

B,D = rotation terms (assumed to be zero)

C,F = translation terms; x,y map coordinates of the center of the upper-left pixel

E = negative of y-scale; dimension of a pixel in map units in y direction

GIS for Planetary Geologic Mappers

pds worldfile
PDS Worldfile
  • PDS uses same – but X,Y are in “pixel” space

Worldfile (MOLA 4ppd megt90n000cb.lbl)

OBJECT = IMAGE_MAP_PROJECTION

^DATA_SET_MAP_PROJECTION = "DSMAP.CAT"

MAP_PROJECTION_TYPE = "SIMPLE CYLINDRICAL"

A_AXIS_RADIUS = 3396.0 <KM>

B_AXIS_RADIUS = 3396.0 <KM>

C_AXIS_RADIUS = 3396.0 <KM>

FIRST_STANDARD_PARALLEL = "N/A"

SECOND_STANDARD_PARALLEL = "N/A"

POSITIVE_LONGITUDE_DIRECTION = "EAST"

CENTER_LATITUDE = 0.0 <DEGREE>

CENTER_LONGITUDE = 180.0 <DEGREE>

REFERENCE_LATITUDE = "N/A"

REFERENCE_LONGITUDE = "N/A"

LINE_FIRST_PIXEL = 1

LINE_LAST_PIXEL = 720

SAMPLE_FIRST_PIXEL = 1

SAMPLE_LAST_PIXEL = 1440

MAP_PROJECTION_ROTATION = 0.0

MAP_RESOLUTION = 4.0 <PIXEL/DEGREE>

MAP_SCALE = 14.818 <KM/PIXEL>

MAXIMUM_LATITUDE = 90.0 <DEGREE>

MINIMUM_LATITUDE = -90.0 <DEGREE>

WESTERNMOST_LONGITUDE = 0.0 <DEGREE>

EASTERNMOST_LONGITUDE = 360.0 <DEGREE>

LINE_PROJECTION_OFFSET = 360.5

SAMPLE_PROJECTION_OFFSET = 720.5

COORDINATE_SYSTEM_TYPE = "BODY-FIXED ROTATING"

COORDINATE_SYSTEM_NAME = "PLANETOCENTRIC"

END_OBJECT = IMAGE_MAP_PROJECTION

14818.0 (meters)

0.0

0.0

-14818.0

-10676369.0 X = SAMPLE_PROJ_OFFSET * MAP_SCALE * -1

5341889.0 Y = LINE_PROJ_OFFSET * MAP_SCALE

http://pds-geosciences.wustl.edu/missions/mgs/megdr.html

GIS for Planetary Geologic Mappers

transition2
Transition
  • Loading PDS and ISIS2,3 Images

GIS for Planetary Geologic Mappers

how to use low level pds
How to use low-level PDS
  • Low-level PDS image is basically “raw” – no map projection – you should not bring it into a GIS
    • Okay how do you map project raw PDS image
      • ISIS - Integrated Software for Imagers and Spectrometers
        • Suse Linux, Solaris UNIX, Mac OSX

http://isis.astrogeology.usgs.gov/

      • VICAR - Video Image Communication And Retrieval

http://www-mipl.jpl.nasa.gov/ also maintained at DLR

GIS for Planetary Geologic Mappers

how to use low level pds1
How to use low-level PDS

http://isis.astrogeology.usgs.gov/IsisSupport/viewtopic.php?t=423

Why:

In short, these programs radiometrically correct the image (level 1) and then geometrically project it through the MOLA DEM to the surface via the spacecraft pointing parameters (SPICE). Again, this is the only way to accurately position the images to the surface for ArcMap or other GIS/RS software. So without “orthorectification” you should not use as a GIS base.

Once a level2 ISIS image is generated, you can use the included ISIS tools or standalone PERL scripts to make them ArcMap compatible as described here: http://isis.astrogeology.usgs.gov/IsisSupport/viewtopic.php?t=357 or http://isis.astrogeology.usgs.gov/IsisSupport/viewtopic.php?t=358The ERDAS raw format works well in ArcMap for multi-band 32bit images like THEMIS. However, when possible it is still a good idea to convert to 8 bit.

GIS for Planetary Geologic Mappers

using high level pds files
Using High-level PDS files

PERL script to add GIS header:> pds2world.pl -e -prj pdsimage.img

Outputs ERDAS raw header. The “-prj” flag supports creation of a Projection file.

for image with detached PDS labels

> pds2world.pl -e -prj pdsimage.lbl

Outputs ERDAS raw header. The “-prj” flag supports creation of a Projection file.

http://webgis.wr.usgs.gov/pigwad/tutorials/scripts/perl.htm

GIS for Planetary Geologic Mappers

using high level pds files1
Using High-level PDS files

More on pds2world.pl (pds2world.exe also available for Windows)

Command line:

pds2world.pl [-bit=8|16] [-r|-g|-t|-c|-j|-p] [-prj] input.img

-r = output raw header and worldfile

-e = output ERDAS raw header and worldfile (8, 16, 32 bit)

-g = output gif worldfile

-t = output tif worldfile

-j = output jpeg worldfile

-J = output jpeg2000 worldfile

-P = output png worldfile

-p = output PCI Aux header (8, 16, 32 bit)

-c = output img header and worldfile (default)

-prj = create ESRI Well Known Text projection file *.prj

Examples:

Create files for 32 bit ERDAS: pds2world.pl -e input.img ---- (good for ERDAS and ArcMap)

Create files for 32 bit ERDAS: pds2world.pl -p input.img ---- (good for GDAL and GDAL conversion)

Create worldfile for tif: pds2world.pl -t input.img ---- (needs another application to convert pds to Tiff)

GIS for Planetary Geologic Mappers

how to use high level isis2
How to use high-level ISIS2

http://isis.astrogeology.usgs.gov/IsisSupport/viewtopic.php?t=357

Does ISIS2 have any routines to convert to an GIS compatible format?

There exist ISIS PERL scripts that one can run on the ISIS files to extract this information into header and worldfiles. These ISIS scripts are:dform.plConvert an ISIS image from 32 or 16 bit to an 8 bit GIS raw, tiff, gif, jpeg with detached GIS files. dform will automatically try to choose a stretch pair for conversion to 8 bit. The user can also specify the stretch pair.

isis2gisworld.plCreates GIS headers and GIS worldfiles for ISIS images so that they can be read into most GIS packages. If you are using ArcMap or ERDAS and wish to maintain a 32 bit file use the ERDAS raw switch " -e ".

Examples:

Converting to an 8bit Tiff with GIS headers: > dform.pl -t -bit=8 -gis=yes isis2image.cub You will end up with two files - the Tiff image, and a Tiff worldfile.

Converting to an 8bit Jpeg with GIS headers: > dform.pl -j=75 -bit=8 -gis=yes isis2image.cub "-j=75" is the Jpeg compression quality (100 is the best). Here, you will end up with two files - the Jpeg image, and a Jpeg worldfile.

Creating GIS headers for a 32bit ISIS cub:> isis2gisworld.pl -e isis2image.cubYou will end up with three files - the ISIS image, a header file "*.raw", and a worldfile "*.rww". This is called an ERDAS raw format. In your GIS you will need to set the NULL ISIS value (more below).

GIS for Planetary Geologic Mappers

high level isis2 files w o isis2
High-level ISIS2 files w/o ISIS2

PERL script to add GIS header:> isis2world.pl -e –prj isis2image.cub

Outputs ERDAS raw header. The “-prj” flag supports creation of a Projection file.

http://webgis.wr.usgs.gov/pigwad/tutorials/scripts/perl.htm

Converting a 16, 32bit ISIS cub to an ESRI ASCII format:> isis2arc myinput.lev2.cub myoutput.ascFree stand-alone C applicaiton (link)

GIS for Planetary Geologic Mappers

using high level isis2 files
Using High-level ISIS2 files

More on isis2world.pl (isis2world.exe also available for Windows)

Command line:

isis2world.pl [-bit=8|16] [-r|-g|-t|-c|-j|-J|-p|-P|-w] [-prj] input.cub

-r = output raw header w/ georefencing (8, 16 bit)

-e = output ERDAS raw header and worldfile (8, 16, 32 bit)

-g = output gif worldfile

-t = output tif worldfile

-w = output generic *.wld worldfile

-J = output jpeg2000 worldfile

-j = output jpeg worldfile

-P = output a png worldfile

-p = output PCI Aux header w/ georefencing (8, 16, 32 bit)

-c = output cub header w/ georef (default) (8, 16 bit)

-prj = create ESRI Well Known Text projection file *.prj

Examples:

Create files for 32 bit ERDAS w/ Projection: isis2world.pl -e -prj input.cub ----- (good for ERDAS and ArcMap)

Create header for 32 bit PCI Aux: isis2world.pl -p input.cub ----- (good for GDAL conversion)

Create worldfile for tif: isis2world.pl -t input.cub ----- (needs program to convert ISIS file to Tiff)

GIS for Planetary Geologic Mappers

how to use high level isis3
How to use high-level ISIS3

ISIS3 can convert images to GIS compatible format

Isis2std – creates 8bit only JPEG, PNG (TIFF) with automatic worldfile

Examples:

Converting to an 8bit Tiff with GIS headers: > Isis2std format=PNG from=myinput.lev2.cub to=myoutput.png

You will end up with two files - the png image, and a png worldfile.

http://isis.astrogeology.usgs.gov/IsisSupport/viewtopic.php?t=357

GIS for Planetary Geologic Mappers

high level isis3 files w o isis3
High-level ISIS3 files w/o ISIS3

PERL script to add GIS header:> isis3world.pl -e –prj isis3image.cub

Outputs ERDAS raw header. The “-prj” flag supports creation of a Projection file.

http://webgis.wr.usgs.gov/pigwad/tutorials/scripts/perl.htm

Note that ISIS3 uses a raw “tiled” internal format. This makes supporting this as a generic raw format harder. The ERDAS raw format fortunately supports tiled images. Other formats may require ISIS3 to output a “BSQ” format instead of a “tiled” format. ISIS3 example:

>crop from=input.cub to=output.cub+bsq

GIS for Planetary Geologic Mappers

using high level isis3 files
Using High-level ISIS3 files

More on isis3world.pl (isis3world.exe also available for Windows)

Command line:

isis3world.pl [-bit=8|16] [-r|-g|-t|-c|-j|-J|-p|-P|-w] [-prj] input.cub

-r = output raw header w/ georefencing (8, 16 bit)

-e = output ERDAS raw header and worldfile (8, 16, 32 bit)

-g = output gif worldfile

-t = output tif worldfile

-J = output jpeg2000 worldfile

-j = output jpeg worldfile

-P = output a png worldfile

-p = output PCI Aux header w/ georefencing (8, 16, 32 bit)

-c = output cub header w/ georef (default) (8, 16 bit)

-prj = create ESRI Well Known Text projection file *.prj

Examples:

Create files for 32 bit ERDAS w/ Projection: isis3world.pl -e -prj input.cub ----- (good for ERDAS and ArcMap)

Create header for 32 bit PCI Aux: isis3world.pl -p input.cub ----- (requires “BSQ” isis3 file, for GDAL conversion)

Create worldfile for tif: isis3world.pl -t input.cub ----- (needs program to convert ISIS file to Tiff)

GIS for Planetary Geologic Mappers

gdal for pds isis2 isis3
GDAL for PDS, ISIS2, ISIS3

GDAL (binaries available using FWtools and OSGeo4W):

> gdal_translate –of GTIFF isis_ver3.cub isis_ver3.tif

>gdal_translate -of JP2KAK -co "quality=20" ophir_geo.cub ophir_geo.jp2

Convert from 32, 16 to 8bit in GDAL

>gdalinfo -stats input.cub

Take min/max output for scale parameters in gdal

>gdal_translate -of GTIFF -ot Byte -a_nodata 0 -scale 0.21 0.89 1 255 input.cub output.jp2

http://isis.astrogeology.usgs.gov/IsisSupport/viewtopic.php?p=6305

GIS for Planetary Geologic Mappers

slide52

Batch Command Line Tip

Batch conversion Tips:

Unix/Linux code:

foreach i (*.cub)

foreach> perl dform.pl -t -gis=yes $i

foreach> end

code:

--------------------------------------------------------------------------------

foreach i (*.cub)

foreach> perl isis2gisworld.pl -e $i

foreach> end

Unix/Linux code:

--------------------------------------------------------------------------------

foreach i (*.cub)

foreach> perl isis2world.pl -e $i

foreach> end

In MsDOS command window loop (for Windows machines)

code:

--------------------------------------------------------------------------------

for %i in (*.cub) do isis2world -e %i

GIS for Planetary Geologic Mappers

lunch
Lunch
  • Next Querying and Spatial Statistics

GIS for Planetary Geologic Mappers

querying the data
Querying the data
  • GIS empowers the user to perform spatial searches across any or all data within a project
  • A “query” is “a request to select features or records from a database or feature”
  • The query expression is typically Boolean (based on yes or no answers)
  • Queries are commonly performed using a dialog box in ArcMap

GIS for Planetary Geologic Mappers

slide55

Let’s say that the user wants to find all units that are labeled “plains material”.

The user will need to query the data as follows.

GIS for Planetary Geologic Mappers

selecting by feature attributes
Selecting by feature attributes
  • Select the layer and field that the query will be based on
  • “Get Unique Values” will give all values in that field
  • Build the query and click “OK”

GIS for Planetary Geologic Mappers

slide58

Selecting by feature location

  • Features can be selected based on relationships with other features
  • Examine the “Select by Location” window for specifics

GIS for Planetary Geologic Mappers

calculating spatial statistics
Calculating Spatial Statistics
  • A powerful tool to calculate statistics of a zone dataset (e.g., geologic units) based on values from a raster dataset (e.g., elevation)
  • Spatial Analyst
    • Cell statistics
    • Neighborhood statistics
    • Zonal statistics
  • Operates out of Spatial Analyst
    • Right click empty space on tool bar and select “Spatial Analyst”

GIS for Planetary Geologic Mappers

cell statistics
Cell Statistics
  • “A function that calculates a statistic for each cell of an output raster that is based on the values of each cell in the same location of multiple input rasters.” - paraphrased from ESRI’s online GIS dictionary
  • For example, the user could find the range and maximum value of albedo from multiple overlapping images acquired in different seasons

“Spatial Analyst tools such as cell statistics provide critical analytical components for the interpretation of raster and vector data. Statistics can help improve the quality of geologic maps.”

GIS for Planetary Geologic Mappers

slide61

1

2

3

  • 1. Add and/or Remove the raster layers that are required for the statistics
  • 2. Set the statistic that is required (can be minimum, maximum, range, sum, mean, std dev, variety, majority, minority, median)
  • 3. Type in the output raster name, either as a temporary file (default - will be erased the next time the project is closed) or as a TIFF, IMG, or Arc GRID.

GIS for Planetary Geologic Mappers

neighborhood statistics
Neighborhood Statistics
  • A function that calculates a statistic on a raster using a user-specified “neighborhood”, which implies an extent from individual cells. The extent can be a annulus, circle, rectangle, or wedge.
  • The user specifies statistics type, neighborhood extent (e.g., circle with a radius of 4 km), and out output cell size (default-input cell size)
  • For example, the user could find the range and maximum value of albedo from multiple overlapping images acquired in different seasons

“Using Neighborhood Statistics, a user could create a range of filter types. For example, a median high pass filter can be produced by using a median neighborhood statistic and then subtracting the raster value.”

GIS for Planetary Geologic Mappers

slide63

1

2

3

4

  • 1. Determine the input dataset and field that will be the basis of the stats
  • 2. Set the statistic (minimum, maximum, range, sum, mean, std dev, variety, majority, minority, median) and the neighborhood (annulus, circle, rectangle, wedge)
  • 3. Set the neighborhood size
  • Set the output cell size, raster name, and location

GIS for Planetary Geologic Mappers

zonal statistics
Zonal Statistics
  • A function that summarizes values in a raster within the zones of another layer
  • The user specifies the “zone dataset” (e.g., geologic units) the value raster dataset (e.g., slope)
  • Output is a Table that summarizes zone statistics
  • For example, the user could find the range and mean value of slope for geologic units

“The Zonal Statistics function allows the user to produce a simplified graph of the statistics. Note the check box in the dialog box.”

GIS for Planetary Geologic Mappers

slide65

1

2

3

  • 1. Set the Zone dataset (the feature that contains the region upon which statistics need to be created)
  • 2. Set the Value raster (the raster dataset that will be the base of the statistics)
  • 3. Set the statistic that is required (can be minimum, maximum, range, sum, mean, std dev, variety, majority, minority, median)

GIS for Planetary Geologic Mappers

break
Break
  • Hands on (Spatial Statistics)
  •  Next: Custom Tools

GIS for Planetary Geologic Mappers

customizing arcmap

Customizing ArcMap

4 Methods for adding functionality to ArcMap

Install downloaded programs

Add built in buttons to menus

Create buttons for custom tools

Use Easy Calculate scripts

GIS for Planetary Geologic Mappers

install downloaded programs
Install downloaded programs
  • Many add-ons available for ArcMap (e.g. X-Tools, Hawth Tools, ArcHydro, etc.)
  • These install like other programs in the windows environment
  • After the program is installed, right click on a blank space in the menu and select the toolbar to add
  • Save the project

GIS for Planetary Geologic Mappers

add buttons for built in functions
Add buttons for built in functions
  • Right click on a blank space in the toolbars
  • Select “Customize” from the drop down menu
  • Click the “Commands” tab
  • Search for commands or select a Category
  • Drag and drop the command to an existing toolbar of your choice
  • Save the project

GIS for Planetary Geologic Mappers

create buttons for custom tools
Create buttons for custom tools
  • Download files from the ESRI website: (http://support.esri.com/index.cfm?fa=downloads.gateway)
  • Search ArcScripts for the tool of interest
  • Be sure that the tool is built for your version of ArcGIS
  • Download the zip file to your computer

GIS for Planetary Geologic Mappers

create buttons for custom tools cont d
Create buttons for custom tools – cont’d
  • Decompress the Zip-File to a folder with a descriptive name
  • Open the “readme.txt” for instructions
  • The instructions are different for different file-types
  • Visual Basic, .DLLs, and Python
  • Avoid Avenue (Old) and AML (Older) scripts

GIS for Planetary Geologic Mappers

use the easy calculate scripts
Use the Easy Calculate Scripts
  • Easy Calculate is a set of expressions (currently 110) for the ArcGIS Field Calculator.
  • Calculate some spatial characteristics of the features, edit the shapes, add records to a target layer, draw graphics etc.
  • http://www.ian-ko.com/free/free_arcgis.htm

GIS for Planetary Geologic Mappers

3d visualization
3D Visualization
  • 3D Analyst

GIS for Planetary Geologic Mappers

worldfile2

*

Worldfile
  • Most simple image registration

5.0 (size of pixel in x direction) – A

0.0 (rotation term for row) - D

0.0 (rotation term for column) - B

-5.0 (size of pixel in y direction) - E

492169.690 (x coordinate of center of upper left pixel in map units) - C

54523.3180 (y coordinate of center of upper left pixel in map units) - F

GIS for Planetary Geologic Mappers

worldfile3
Worldfile
  • Algebraic Form (six parameter affine transformation)

x’ = Ax + By + C

y’ = Dx + Ey + F

where

x’ = calculated x-coordinate of the pixel on the map

y’ = calculated y-coordinate of the pixel on the map

x = column number of a pixel in the image

y = row number of a pixel in the image

A = x-scale; dimension of a pixel in map units in x direction

B,D = rotation terms (assumed to be zero)

C,F = translation terms; x,y map coordinates of the center of the upper-left pixel

E = negative of y-scale; dimension of a pixel in map units in y direction

GIS for Planetary Geologic Mappers

pds worldfile1
PDS Worldfile
  • PDS uses same – but X,Y are in “pixel” space

Worldfile (MOLA 4ppd megt90n000cb.lbl)

OBJECT = IMAGE_MAP_PROJECTION

^DATA_SET_MAP_PROJECTION = "DSMAP.CAT"

MAP_PROJECTION_TYPE = "SIMPLE CYLINDRICAL"

A_AXIS_RADIUS = 3396.0 <KM>

B_AXIS_RADIUS = 3396.0 <KM>

C_AXIS_RADIUS = 3396.0 <KM>

FIRST_STANDARD_PARALLEL = "N/A"

SECOND_STANDARD_PARALLEL = "N/A"

POSITIVE_LONGITUDE_DIRECTION = "EAST"

CENTER_LATITUDE = 0.0 <DEGREE>

CENTER_LONGITUDE = 180.0 <DEGREE>

REFERENCE_LATITUDE = "N/A"

REFERENCE_LONGITUDE = "N/A"

LINE_FIRST_PIXEL = 1

LINE_LAST_PIXEL = 720

SAMPLE_FIRST_PIXEL = 1

SAMPLE_LAST_PIXEL = 1440

MAP_PROJECTION_ROTATION = 0.0

MAP_RESOLUTION = 4.0 <PIXEL/DEGREE>

MAP_SCALE = 14.818 <KM/PIXEL>

MAXIMUM_LATITUDE = 90.0 <DEGREE>

MINIMUM_LATITUDE = -90.0 <DEGREE>

WESTERNMOST_LONGITUDE = 0.0 <DEGREE>

EASTERNMOST_LONGITUDE = 360.0 <DEGREE>

LINE_PROJECTION_OFFSET = 360.5

SAMPLE_PROJECTION_OFFSET = 720.5

COORDINATE_SYSTEM_TYPE = "BODY-FIXED ROTATING"

COORDINATE_SYSTEM_NAME = "PLANETOCENTRIC"

END_OBJECT = IMAGE_MAP_PROJECTION

14818.0 (meters)

0.0

0.0

-14818.0

-10676369.0 X = SAMPLE_PROJ_OFFSET * MAP_SCALE * -1

5341889.0 Y = LINE_PROJ_OFFSET * MAP_SCALE

http://pds-geosciences.wustl.edu/missions/mgs/megdr.html

GIS for Planetary Geologic Mappers

questions
Questions?

GIS for Planetary Geologic Mappers