GEOG585: Internet Mapping: Lab 10

Question 1

Log into the class server (129.24.63.138) using PuTTY and the username and password
supplied for your class account. Create a new directory named "lab10data" in your home
directory, and "cd" into it. Execute the following command (which copies a file from another
directory into the current working directory - don't forget the trailing "." - and yes, the
filename is "Lab08data.zip") to copy the data for this lab into your newly created directory

cp ~kbene/Lab08data.zip .

This archive contains ten datasets downloaded from the USGS National Map Seamless
Server (http://seamless.usgs.gov/website/seamless/viewer.htm), and contains, otherwise
unmodified file directories as they were delivered from their system. Done.

Question 2

Uncompress the transferred zip file using the Linux 'unzip' command. Each of the resulting
directories (except the "__MACOSX" one) contain the data and metadata for each of the
downloaded datasets. Answer the following questions about each of the downloaded data
sets (You can earn 5 bonus points if you can figure out how to access and use the
NED_30249657 dataset.):

What is the name of the dataset?
What spatial domain does it cover?
What is the projection (coordinate system)?
What format is it in?

To answer these questions about each dataset you may need to use ogrinfo, gdalinfo, and/
or you may also use the 'lynx' web browser (e.g. "lynx 09307994\\meta1.html") to read
the .html metadata file included with each of the downloaded files.

09307994

Name:
Shuttle Radar Topography Mission (SRTM) Elevation Data Set
Domain:
West_Bounding_Coordinate:-106.63079927
East_Bounding_Coordinate:-106.60999075
North_Bounding_Coordinate:35.09173596
South_Bounding_Coordinate:35.07505475
Projection:
D_WGS_1984
Format:
SDE raster digital data

36033381

Name:
USGS High Resolution Orthoimagery for the Albuquerque, New Mexico Urban Area
Domain:
West_Bounding_Coordinate:-106.62039501
East_Bounding_Coordinate:-106.60999075
North_Bounding_Coordinate:35.08061516
South_Bounding_Coordinate:35.07505475
Projection:
Universal Transverse Mercator 13
Format:
SDE raster digital data

50647444

Name:
Roads: United States and Puerto Rico
Domain:
West_Bounding_Coordinate:-106.63079927
East_Bounding_Coordinate:-106.60999075
North_Bounding_Coordinate:35.09173596
South_Bounding_Coordinate:35.07505475
Projection:
Universal Transverse Mercator 13
Format:
vector digital data

50717270

Name:
USGS High Resolution Orthoimagery for the Albuquerque, New Mexico Urban Area
Domain:
West_Bounding_Coordinate:-106.63079927
East_Bounding_Coordinate:-106.62039501
North_Bounding_Coordinate:35.09173596
South_Bounding_Coordinate:35.08617556
Projection:
Universal Transverse Mercator 13
Format:
SDE raster digital data

56892286

Name:
USGS High Resolution State Orthoimagery for New Mexico 2005
Domain:
West_Bounding_Coordinate:-106.63079927
East_Bounding_Coordinate:-106.60999075
North_Bounding_Coordinate:35.09173596
South_Bounding_Coordinate:35.07505475
Projection:
Universal Transverse Mercator 13
Format:
SDE raster digital data

84943361

Name:
USGS High Resolution Orthoimagery for the Albuquerque, New Mexico Urban Area
Domain:
West_Bounding_Coordinate:-106.62039501
East_Bounding_Coordinate:-106.60999075
North_Bounding_Coordinate:35.09173596
South_Bounding_Coordinate:35.08617556
Projection:
Universal Transverse Mercator 13
Format:
SDE raster digital data

89210636

Name:
USGS High Resolution Orthoimagery for the Albuquerque, New Mexico Urban Area
Domain:
West_Bounding_Coordinate:-106.62039501
East_Bounding_Coordinate:-106.60999075
North_Bounding_Coordinate:35.08617556
South_Bounding_Coordinate:35.08061516
Projection:
Universal Transverse Mercator 13
Format:
SDE raster digital data

95906696

Name:
USGS High Resolution Orthoimagery for the Albuquerque, New Mexico Urban Area
Domain:
West_Bounding_Coordinate:-106.63079927
East_Bounding_Coordinate:-106.62039501
North_Bounding_Coordinate:35.08617556
South_Bounding_Coordinate:35.08061516
Projection:
Universal Transverse Mercator 13
Format:
SDE raster digital data

97127531

Name:
USGS High Resolution Orthoimagery for the Albuquerque, New Mexico Urban Area
Domain:
West_Bounding_Coordinate:-106.63079927
East_Bounding_Coordinate:-106.62039501
North_Bounding_Coordinate:35.08061516
South_Bounding_Coordinate:35.07505475
Projection:
Universal Transverse Mercator 13
Format:
SDE raster digital data

NED_30249657

Name:
1-Arc Second National Elevation Dataset
Domain:
West_Bounding_Coordinate:-106.63079927
East_Bounding_Coordinate:-106.60999075
North_Bounding_Coordinate:35.09173596
South_Bounding_Coordinate:35.07505475
Projection:
North American Datum of 1983
Format:
SDE raster digital data

Question 3

Create a new directory in your "lab10data" directory called "lab10imagery" and copy
the .tif, .tfw, and .prj files from the 6 files entitled "USGS High Resolution Orthoimagery for
the Albuquerque, New Mexico Urban Area" as indicated in the .html metadata. Done.

Question 4

Run gdalinfo on one of the .tif files and copy the output into a text editor so you can look at it
later. Create external overviews for each of the six .tif files using the gdaladdo command,
following the following example

gdaladdo --config USE_RRD YES "36033381\36033381.tif" 2 4 8 16 32 64

Run gdalinfo on the same file you ran it on before running gdaladdo. What difference to you
see between the outputs (hint: the change is in each of the "Band" sections)? Include in your
writeup a snippet from both gdalinfo commands that illustrates the change.

Before:
Band 2 Block=6392x1 Type=Byte, ColorInterp=Green
Min=0.000 Max=255.000
Minimum=0.000, Maximum=255.000, Mean=117.957, StdDev=54.503

After: *.AUX file created and:
Band 2 Block=6392x1 Type=Byte, ColorInterp=Green
Min=0.000 Max=255.000
Minimum=0.000, Maximum=255.000, Mean=117.957, StdDev=54.503
Overviews: 3196x2107, 1598x1054, 799x527, 400x264, 200x132, 100x66

Question 5

Generate a tile index for the six rasters moved in question 3 using the gdaltindex command,
following the following example (from within the directory containing the 6 .tif files).
gdaltindex abqimagery.shp ./*.tif Done. (Very handy command, I'll be using this a lot)

Run ogrinfo for the single layer within the generated shape file and include the output in your
writeup.

INFO: Open of `abqimagery.shp'
      using driver `ESRI Shapefile' successful.

Layer name: abqimagery
Geometry: Polygon
Feature Count: 6
Extent: (351315.900000, 3882551.700000) - (353243.250000, 3884432.850000)
Layer SRS WKT:
(unknown)
location: String (255.0)
OGRFeature(abqimagery):0
  location (String) = ./36033381\36033381.tif
  POLYGON ((352264.650000000023283 3883183.800000000279397,353223.450000000011642 3883183.800000000279397,353223.450000000011642 3882551.700000000186265,352264.650000000023283 3882551.700000000186265,352264.650000000023283 3883183.800000000279397))

OGRFeature(abqimagery):1
  location (String) = ./50717270\50717270.tif
  POLYGON ((351336.150000000023283 3884432.850000000093132,352294.799999999871943 3884432.850000000093132,352294.799999999871943 3883800.450000000186265,351336.150000000023283 3883800.450000000186265,351336.150000000023283 3884432.850000000093132))

OGRFeature(abqimagery):2
  location (String) = ./84943361\84943361.tif
  POLYGON ((352284.599999999976717 3884417.25,353243.25 3884417.25,353243.25 3883785.0,352284.599999999976717 3883785.0,352284.599999999976717 3884417.25))

OGRFeature(abqimagery):3
  location (String) = ./89210636\89210636.tif
  POLYGON ((352274.549999999988358 3883800.600000000093132,353233.349999999976717 3883800.600000000093132,353233.349999999976717 3883168.350000000093132,352274.549999999988358 3883168.350000000093132,352274.549999999988358 3883800.600000000093132))

OGRFeature(abqimagery):4
  location (String) = ./95906696\95906696.tif
  POLYGON ((351325.950000000011642 3883816.049999999813735,352284.749999999883585 3883816.049999999813735,352284.749999999883585 3883183.649999999906868,351325.950000000011642 3883183.649999999906868,351325.950000000011642 3883816.049999999813735))

OGRFeature(abqimagery):5
  location (String) = ./97127531\97127531.tif
  POLYGON ((351315.900000000023283 3883199.399999999906868,352274.699999999895226 3883199.399999999906868,352274.699999999895226 3882567.0,351315.900000000023283 3882567.0,351315.900000000023283 3883199.399999999906868))

What is the coordinate system of the generated shape file? Unknown

What should it be? UTM 13

Run the following command to generate a new shapefile for which the projection is
specified. Run ogr2ogr on it and note the change in the output. What difference to you see,
and why?

ogr2ogr -s_srs "EPSG:26913" -a_srs "EPSG:26913" abqimagery_utm.shp abqimagery.shp

The EPSG code projection data was applied to the shapefile. I presume this is similar to 'Define Projection' in ArcMap.

INFO: Open of `abqimagery_utm.shp'
      using driver `ESRI Shapefile' successful.

Layer name: abqimagery_utm
Geometry: Polygon
Feature Count: 6
Extent: (351315.900000, 3882551.700000) - (353243.250000, 3884432.850000)
Layer SRS WKT:
PROJCS["NAD_1983_UTM_Zone_13N",
    GEOGCS["GCS_North_American_1983",
        DATUM["North_American_Datum_1983",
            SPHEROID["GRS_1980",6378137,298.257222101]],
        PRIMEM["Greenwich",0],
        UNIT["Degree",0.017453292519943295]],
    PROJECTION["Transverse_Mercator"],
    PARAMETER["latitude_of_origin",0],
    PARAMETER["central_meridian",-105],
    PARAMETER["scale_factor",0.9996],
    PARAMETER["false_easting",500000],
    PARAMETER["false_northing",0],
    UNIT["Meter",1]]
location: String (255.0)
OGRFeature(abqimagery_utm):0
  location (String) = ./36033381\36033381.tif
  POLYGON ((352264.650000000023283 3883183.800000000279397,353223.450000000011642 3883183.800000000279397,353223.450000000011642 3882551.700000000186265,352264.650000000023283 3882551.700000000186265,352264.650000000023283 3883183.800000000279397))

OGRFeature(abqimagery_utm):1
  location (String) = ./50717270\50717270.tif
  POLYGON ((351336.150000000023283 3884432.850000000093132,352294.799999999871943 3884432.850000000093132,352294.799999999871943 3883800.450000000186265,351336.150000000023283 3883800.450000000186265,351336.150000000023283 3884432.850000000093132))

OGRFeature(abqimagery_utm):2
  location (String) = ./84943361\84943361.tif
  POLYGON ((352284.599999999976717 3884417.25,353243.25 3884417.25,353243.25 3883785.0,352284.599999999976717 3883785.0,352284.599999999976717 3884417.25))

OGRFeature(abqimagery_utm):3
  location (String) = ./89210636\89210636.tif
  POLYGON ((352274.549999999988358 3883800.600000000093132,353233.349999999976717 3883800.600000000093132,353233.349999999976717 3883168.350000000093132,352274.549999999988358 3883168.350000000093132,352274.549999999988358 3883800.600000000093132))

OGRFeature(abqimagery_utm):4
  location (String) = ./95906696\95906696.tif
  POLYGON ((351325.950000000011642 3883816.049999999813735,352284.749999999883585 3883816.049999999813735,352284.749999999883585 3883183.649999999906868,351325.950000000011642 3883183.649999999906868,351325.950000000011642 3883816.049999999813735))

OGRFeature(abqimagery_utm):5
  location (String) = ./97127531\97127531.tif
  POLYGON ((351315.900000000023283 3883199.399999999906868,352274.699999999895226 3883199.399999999906868,352274.699999999895226 3882567.0,351315.900000000023283 3882567.0,351315.900000000023283 3883199.399999999906868))