[GRASS5] adding metadata in GRASS 5.7
Helena
hmitaso at unity.ncsu.edu
Thu Sep 2 10:02:35 EDT 2004
Radim,
metadata can be quite large so it would be useful to have a separate file for
it. I don't know whether it is possible to add it to GRASS5.7 at this point
but they are very important, as they often include information about the
data accuracy, when exactly the survey was made, who is the point of contact,
what kind of processing was done to the data and anything else that the data creator
may consider important. US has a standard metadata form that is provided
for each data set - attached is an example of standard metadata file.
It does not have to be so detailed, but a lot of the information provided
in this file is essential when this data are to be combined with data
from other sources.
I am sure that for many users it is important to be able to edit the metadata,
especially if one wants to add some comments about the processing that was done
to the file within GRASS. So at least to keep the capabilities for handling
metadata as in 5.3 is needed.
Helena
Radim Blazek wrote:
> On Thursday 02 September 2004 10:34, Otto Dassau wrote:
>
>>Dear list,
>>
>>I would like to add metadata to maps in GRASS 5.7 but I can't find any
>>modules to edit related history files in the directory /hist.
>>
>>For raster data in GRASS 5.0 and 5.3 r.support allows to add additional
>>comments, but this module doesn't exist in GRASS 5.7 anymore.
>>
>>For vector data, the old v.digit allows to add comments but the new
>>digitizing tool does not.
>>
>>Does there already exist a module to add metadata, is this simply missing
>>yet or will metadata be handled totally different in GRASS 5.7?
>
>
> I think that vector metadata should be stored in 'head', not in 'hist'.
> Currently there are no tools for manipulation of user metadata in 'head' file.
> Which kind of metadata?
>
> Radim
>
> _______________________________________________
> grass5 mailing list
> grass5 at grass.itc.it
> http://grass.itc.it/mailman/listinfo/grass5
-------------- next part --------------
Identification_Information:
Citation:
Citation_Information:
Originator: Coastal Remote Sensing/Coastal Services Center
Publication_Date: 20040713
Title:
Aircraft Laser/GPS Mapping of Coastal Topography.
Other_Citation_Details:
This data set has been extracted from one much larger.
See the URL for the location of this larger data set.
Online_Linkage: http://www.csc.noaa.gov/lidar
Description:
Abstract:
This data set consists of 2271705 records of x,y, and z values.
Laser beach mapping uses a pulsed laser ranging system mounted onboard an aircraft to measure ground
elevation and coastal topography. The laser emits laser beams at high frequency and is directed downward at the
earth's surface through a port opening in the bottom of the aircraft's fuselage. The laser system records the
time difference between emission of the laser beam and the reception of the reflected laser signal in the
aircraft. The aircraft travels over the beach at approximately 60 meters per second while surveying from
the low water line to the landward base of the sand dunes.
Purpose:
This data was collected as part of an effort to map beach
topography efficiently and cheaply.
Supplemental_Information:
This data set was collected with a LIDAR
(LIght Detection And Ranging) instrument designed and
developed by the Observational Sciences Branch (OSB) of
NASA at the Wallops Flight Facility in Virginia. The
instrument, originally designed for mapping ice sheets
in Greenland, is called the Airborne Topographic Mapper
or ATM. The ATM II (the latest version), operates with
a Spectra Physics laser transmitter, which provides a
7 nanoseconds long, 250 microjoules pulse at a
frequency-doubled wavelength of 523 nanometers in the
blue-green spectral region. The laser transmitter
can function at pulse rates from 2 to 10 kilohertz
(kHz). The laser system with a separate cooling unit
weighs approximately 45 kilograms (kg) and requires
approximately 15 amperes of power at 115 volts.
The transmitted laser pulse is reflected to the surface
of the earth with the aid of a small folding mirror mounted
on the back of a secondary mirror of a rotating scan
mirror assembly mounted directly in front of the
telescope. The scan mirror, which is rotated at 20
hertz, is comprised of a section of round aluminum
stock, machined to a specific off-nadir angle.
A scan mirror with the off-nadir angle of 15 degrees
was utilized, producing an elliptical scan pattern
with a swath width equal to 50 percent of the
approximately 700-meter aircraft altitude. The reflected
laser pulse is transmitted to a photo-multiplier
assembly that consists of a lens, a narrow bandpass
filter, and a single photomultiplier tube.
Note: The Spatial Reference section of this document
may lack fully FGDC-compliant information regarding
projection parameters (i.e., Central meridian, false
Northing, etc.). The State Plane or UTM Zone will be
supplied, and the corresponding parameters can be found
in Appendix C of:
Snyder, John, 1987, Map Projections, a Working Manual
(U.S. Geological Survey Professional Paper 1395):
Washington, U.S. Government Printing Office.
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 19990909
Ending_Date: 19991008
Currentness_Reference:
Ground condition
Status:
Progress: Complete
Maintenance_and_Update_Frequency:
None planned
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -75.645249
East_Bounding_Coordinate: -75.619915
North_Bounding_Coordinate: 35.968653
South_Bounding_Coordinate: 35.946432
Keywords:
Theme:
Theme_Keyword_Thesaurus: GCMD
Theme_Keyword:
EARTH SCIENCE > LAND SURFACE > Topography > Terrain Elevation
Theme:
Theme_Keyword_Thesaurus: None
Theme_Keyword: lidar
Theme_Keyword: laser
Theme_Keyword: beach
Theme_Keyword: topography
Theme_Keyword: digital elevation model
Theme_Keyword: DEM
Theme_Keyword: erosion
Place:
Place_Keyword_Thesaurus: None
Place_Keyword: U.S. Coastline
Access_Constraints:
This data set was compiled dynamically, and will exist on
ftp.csc.noaa.gov/pub/crs/beachmap/data until 10 days after
07/13/2004, as hmitaso30088_raw.zip. After 10 days this file will be
deleted from the system.
Use_Constraints:
This data was collected for the purposes of research.
Any conclusions drawn from analysis of this information
are not the responsibility of NOAA or the Coastal Services
Center.
Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
Coastal Remote Sensing Program
Contact_Position: TCM Project Scientist
Contact_Address:
Address_Type: mailing and physical address
Address:
2234 South Hobson Avenue
City: Charleston
State_or_Province: South Carolina
Postal_Code: 29405
Country: United States
Contact_Voice_Telephone: (843) 740-1200
Contact_Electronic_Mail_Address: csc at csc.noaa.gov
Data_Set_Credit:
Airborne Topographic Mapper LIDAR data were collected in partnership
with the National Oceanic and Atmospheric Administration (NOAA) Coastal
Services Center, the NASA Wallops Flight Facility, the U. S. Geological
Survey (USGS) Center for Coastal and Regional Marine Geology, and the
NOAA Aircraft Operations Center.
Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report:
Raw elevation measurements have been determined to be vertically accurate
to within 15 cm. Processing steps (datum conversion, projection, grid
interpolation, etc.) introduce additional error factors which have not
been tested at the time of this publication.
Logical_Consistency_Report:
Not applicable.
Completeness_Report:
All elevation data points that appeared to be within a reasonable vertical
range were retained, and other points were thrown away. This filtering process
was performed 'by eye'.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
The ATM LIDAR elevation points are known to be horizontally accurate
to +/- 0.8 meters at an aircraft altitude of 700 meters.
Vertical_Positional_Accuracy:
Vertical_Positional_Accuracy_Report:
The ATM LIDAR elevation measurements have been found to be within +/-
15 centimeters of each other in successive and overlapping passes of
the same area. In comparisons of LIDAR data for a small geographic region
with various ground surveys the differences are between +/- 15 to
20 centimeters. The accuracy of the majority of the data is estimated
to be consistent with the above stated results. At this time, there has been
no large scale verification of the data.
Lineage:
Process_Step:
Process_Description:
The vertical values in this data set have been
filtered through visual inspection to find abnormally high
and abnormally low values. In addition, this data
was processed using a spatial filtering program that identifies
and discards outlier elevation measurements. This program reads
each elevation measurement within a file and identifies "spatially close"
points (i.e. those neighboring points within a fixed radius of the point).
The mean and standard deviation is calculated using the elevations of these
points. If the elevation difference from the mean of the point under consideration
is more than 2 standard deviations and greater than a defined distance
the point is discarded.
Process_Date: Unknown
Process_Step:
Process_Description:
The horizontal and vertical values in this data set have been
converted from the ITRF94 spatial reference system to the NAD83
spatial reference system. The algorithm used was obtained from
the National Geodetic Survey.
Process_Date: 20040713
Process_Step:
Process_Description:
The vertical values in this data set have been converted to reference
NGVD29, using the VERTCON software provided by the National Geodetic
Survey.
Process_Date: 20040713
Process_Step:
Process_Description:
The data values in this data set have been projected. This projection
is noted in another section of this metadata record. The software
used was developed by the United States Geological Survey, National
Mapping Division.
Process_Date: 20040713
Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Point
Point_and_Vector_Object_Information:
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: Point
Point_and_Vector_Object_Count: 2271705
Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Planar:
Grid_Coordinate_System:
Grid_Coordinate_System_Name:
State Plane Coordinate System 1983
State_Plane_Coordinate_System:
SPCS_Zone_Identifier: 3200
Planar_Coordinate_Information:
Planar_Coordinate_Encoding_Method:
coordinate pair
Coordinate_Representation:
Abscissa_Resolution: 0.295212617917293
Ordinate_Resolution: 0.3647066112
Planar_Distance_Units: survey feet
Geodetic_Model:
Horizontal_Datum_Name:
North American Datum of 1983
Ellipsoid_Name:
Geodetic Reference System 80
Semi-major_Axis:
6378137
Denominator_of_Flattening_Ratio:
298.257
Vertical_Coordinate_System_Definition:
Altitude_System_Definition:
Altitude_Datum_Name:
National Geodetic Vertical Datum of 1929
Altitude_Resolution: 0.0328
Altitude_Distance_Units: feet
Altitude_Encoding_Method:
Explicit elevation coordinate included with horizontal coordinates
Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
NOAA Coastal Services Center
Contact_Position: Coastal Remote Sensing Program Manager
Contact_Address:
Address_Type: mailing and physical address
Address: 2234 South Hobson Avenue
City: Charleston
State_or_Province: SC
Postal_Code: 29405-2413
Contact_Voice_Telephone: none
Contact_Electronic_Mail_Address: csc at csc.noaa.gov
Distribution_Liability:
This data was collected for the purposes of research.
Any conclusions drawn from analysis of this information
are not the responsibility of NOAA or the Coastal Services
Center.
Custom_Order_Process:
This data can be obtained on-line at the following URL:
http://www.csc.noaa.gov/ldart. The data set is dynamically generated based on
user-specified parameters.
Metadata_Reference_Information:
Metadata_Date: 19980331
Metadata_Review_Date: 19980331
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
NOAA Coastal Services Center
Contact_Position: Metadata Specialist
Contact_Address:
Address_Type: mailing and physical address
Address: 2234 South Hobson Avenue
City: Charleston
State_or_Province: SC
Postal_Code: 29405-2413
Contact_Voice_Telephone: none
Contact_Electronic_Mail_Address: metadata at csc.noaa.gov
Metadata_Standard_Name:
FGDC Content Standards for Digital
Geospatial Metadata
Metadata_Standard_Version:
FGDC-STD-001-1998
More information about the grass-dev
mailing list