DISCUSSION PAPER NO. 95

DATE: May 24 1996
REVISED:

NAME: Enhancements to field 007 (Map) for Remote-Sensing Images in the Bibliographic and Holdings Formats

SOURCE: Committee on Cataloging and Classification, Map and Geography Round Table

SUMMARY: This proposal suggests defining six new character positions for information related to the physical description of remote-sensing images in field 007 (Physical Description Fixed Field) for maps.

KEYWORDS: Field 007 (Bibliographic/Holdings); Remote-sensing images; Physical Description Fixed Field

RELATED:

STATUS/COMMENTS:

5/24/1996 - Forwarded to USMARC Advisory Group for discussion at the July 1996 MARBI meetings.

7/7/96 - There was a distinct preference to make the data elements a new 007 rather than including them as an extension of the Map 007. Since they are essential to the Can/MARC alignment proposal, they will be a proposal at the next meeting. The map community said they wanted to refine the values for the recording technique.


DISCUSSION PAPER NO. 95: Enhancements to field 007 (Map) 
for Remote-Sensing Images

1.  INTRODUCTION

For many years it has been possible to encode certain physical
characteristics of maps in the eight character positions defined in
the maps field 007.  When the cartographic item is a remote-sensing
image (i.e., when field 007 character position 00 contains code a
and 01 contains code r), the currently-defined positions are not
adequate to encode all the physical characteristics that might be
desired in coded form.  The Committee on Cataloging and
Classification, Map and Geography Round Table has identified
several data elements that are important for the retrieval of
remote-sensing images.  The cartographic cataloging community would
like to include these new data elements in machine-readable records
and has determined that the data would be most useful if
represented in coded form.  They have asked MARBI to consider
defining new character positions for them.

This Discussion Paper describes seven (7) new bytes for the field
007 (Physical Description Fixed Field) for maps in the USMARC
Bibliographic and Holdings formats to accommodate additional
information related to remote-sensing images.  The changes proposed
will permit the encoding of information relating to altitude of
sensor, attitude of sensor, cloud cover, platform construction
type, platform use category, and recording technique.  That
information is currently coded by the National Archives of Canada
in a 009 field and, as part of format harmonization, Canada would
like to bring the coding into non-local fields in the format.  Six
of the elements in the CAN/MARC field 009 are accommodated below.


2.  DISCUSSION

The physical characteristics related to remote-sensing images that
are not yet accommodated by the maps 007 are collectively referred
to as "coverage" information.  Representing this information in
coded form is needed to allow systems to limit searching to known
items that represent images with coverage meeting the desired
characteristics.  Most of these categories of information are
fairly straightforward.  The specific categories of information
with proposed values and character positions are given below. 

1) Position of the remote sensing devise.

The position of the remote sensing devise involves two distinct
aspects, altitude and attitude, thus, two new field 007 positions
would be needed.   

     08   Altitude of sensor
          a   Terrestrial (on Earth)
          b   Aerial (from aircraft, balloon, etc.)
          c   Space (from spacecraft)
          n   Not applicable
          u   Unknown
          z   Other
     09   Attitude of sensor
          a   Low oblique (without horizon)
          b   High oblique (shows horizon)
          c   Vertical
          n   Not applicable
          u   Unknown
          z   Other

2) Presence of clouds when the image was taken. 

Cloud cover can be handled by a single position with numeric codes
representing percentage of cloud cover in increments of 10%.  The
division of cloud cover requested in this proposal differs somewhat
from similar data elements in other formats where, for example,
only 8 increments may be defined.  The Map and Geography Round
Table is asking for 10 increments for two reasons.  First of all,
they want to align the data element for remote-sensing images to
geospatial metadata, which uses increments of 10%.  They indicated
that despite suggestions that land images with more than 10% cloud
cover are unusable, images cover the full range of views of the
Earth from a distance taken from various platforms.

     10   Cloud cover
          0   0-9%
          1   10-19%
          2   20-29%
          3   30-39%
          4   40-49%
          5   50-59%
          6   60-69%
          7   70-79%
          8   80-89%
          9   90-100%
          n   Not applicable
          u   Unknown

3) Characteristics of the platform from which the image was taken. 

Physical description of the platform from which an image is taken
involves two aspects, the platform construction type (i.e., whether
the platform is a balloon, a spacecraft, etc.) and the platform use
category (i.e., whether the platform is used for meteorological
images, images of space, etc.)

     11   Platform construction type
          a   Balloon
          b   Aircraft--low altitude (<29,500 ft.)
          c   Aircraft--medium altitude (29,500-49,000 ft.)
          d   Aircraft--high altitude (>49,000 ft.)
          e   Manned spacecraft
          f   Unmanned spacecraft
          n   Not applicable
          u   Unknown
          z   Other
     12   Platform use category
          a   Meteorological
          b   Earth resources
          c   Space observing
          m   Multi-tasking
          n   Not applicable
          u   Unknown
          z   Other

4) The actual sensing technique used to make the image.  

Recording technique is more complex and needs two positions to
allow for future expansion of values.  The set of values given
below are a preliminary set and analysis is underway in Canada for
completion of the set.

     13-14  Recording technique
          nn   Not applicable
          uu   Unknown
          vv   Combination of various recording technique methods
          zz   Other
                    Light emission
          aa   Video tape
          ab   False color
          ac   Multispectral photography
          ad   Multispectral scanning
          au   Light emission, unknown method           
          av   Combination of various light emission techniques
          az   Other light emission technique
                    Thermal infrared scanning
          da   Infrared line scanning
          du   Thermal infrared scanning, unknown method
          dv   Combination of various thermal infrared techniques
          dz   Other thermal infrared scanning technique 
                    Microwave emission
          ga   Sidelooking airborne radar (SLAR)
          gb   Synthetic apeture radar (SAR)
          gc   Passive microwave mapping
          gu   Microwave emission, unknown method
          gv   Combination of various microwave emission techniques
          gz   Other microwave emission technique

For occurrences of map field 007 when 007/01 contains a code other
than r, the newly-defined character positions 007/08-14 will
contain code n (Not applicable).  As remote-sensing images become
more widely available and as the platforms from which the images
are taken become more diverse, the need for providing an area to
describe the physical aspects of the images grows.  


3.  QUESTIONS

Since these newly-defined character positions will only apply to
remote-sensing images, should the names of the new positions
include "for remote-sensing images"?  The addition to the names
would make them a bit long, for example, position 13-14 would be
called: Recording technique for remote-sensing image.

Should all occurrences of 007 be required to be 15 characters long
or should the approach used for motion pictures be used (that 007
is either 8 or 23 bytes long). If the former is selected should
existing occurrences of the maps 007 be converted to add the
missing bytes?


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