PHOTOGRAMMETRIC ENGINEERING & REMOTE SENSING
July 2014
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taken with the optical axis of the camera kept within 5°
of the vertical.
•
Ortho
– Images geometrically corrected for topographic
relief, lens distortion, and camera tilt, to ensure a uni-
form scale.
•
Oblique images –
An aerial photograph taken with the
optical axis of the camera deliberately pointed away from
the vertical. Oblique photographs could therefore be de-
fined as photographs usually taken with the optical axis
more than 5° from the vertical. Enables at-an-angle view
of properties, etc.; from different directions.
•
Ground Control –
Previously georeferenced feature(s)
which include metadata that references the accuracy,
collection procedures, methodologies, and/or source
data.
•
Vector Road and Street Data –
Standard off-the-
shelf data sets with geospatially accurate road and
street data with addressing. Typically these data prod-
ucts include Points of Interest (POI) such as hotels, fuel
stations, schools, and airports. A vector represents a
physical quantity or feature having both length and di-
rection.
•
Parcel Data
– Parcel data includes attributes such as
property description, zoning, ownership, and appraised
or market value. These data sets are typically available
by city, county or state. A parcel is a single piece of land
described in a single description in a deed or as one of a
number of lots on a plat, separately owned either public-
ly or privately and capable of being conveyed separately.
•
Land Use Data –
Commercially or government fur-
nished data sets of land use are provided for planning
activities. Products are available for local and regional
assessment.
•
Digital Elevation Model (DEM) –
a digital model or
3-D representation of a terrain’s surface.
◊
Digital terrain model (DTM) –
a bare-earth model
in which cultural features such as buildings, roads,
and vegetation canopy are digitally removed using
processing software.
◊
Digital surface model (DSM) –
a first-reflec-
tive-surface model that contains cultural features
such as buildings, roads, vegetation, and natural
terrain features.
•
Orthorectified radar image (ORI) –
a grayscale im-
age of the earth’s surface roughness that has been cor-
rected to remove geometric distortions.
•
Elevation shaded image (ESI) –
a multi-spectral im-
age composed of a DEM overlaid with high-resolution
aerial images to provide an enhanced visual represen-
tation of the terrain that cannot be duplicated with or-
dinary images. As the name suggests, a shaded relief
product draws out terrain features and is more intuitive
than either the DSM or DTM on which it is based.
•
Hosted / Online Data –
Defined as Data as a Service
(DaaS), this refers to the data product that can be pro-
vided under a subscription model and may be provided
under a Software as a Service (SaaS) application.
There are several methods for the delivery of CGMP. These
include but are not limited to a shrink wrapped package, down-
load from a web service or online store, shipped via electronic
media or via “the cloud.” The delivery method will be defined
by the provider and driven by market demand. “Metadata” is
an additional feature of many of the products noted.
NOTE:
Specific contracts may require an appropriately li-
censed professional to meet requirements for State Laws or
project scope of work. The professional should be responsible
for the research of data available, fit for use of data, and inte-
gration of the products described above.
Product Support
In order to fulfill warranties as defined within the user license,
CGMP providers may offer customer product support. Product
support can also be offered to the public under similar terms
and conditions or sold competitively in substantial quantities
based on established catalog or market prices. For the purpose
of these
Guidelines
product support is limited to:
•
Installation –
The act of installing the required CGMP
into a customer test and/or production environment.
Customer service and help desk are also covered.
•
Data Reformatting
– The process of changing the de-
livery format so that it may be optimally used in the
customers’ system(s). May also include changing file for-
mats of data delivery and orders of occurrence of data
to match customer needs for automated use of CGMP.
•
Maintenance –
That which may be required to fulfill
the product warranty as defined within the user license.
•
Training
- The transfer of knowledge, skills, and com-
petencies that relate to the use of the CGMP.
V. Procurement of CGMP
The following are considered best practices for the procure-
ment of CGMP.
•
Pre-proposal research, including requirements
definition
◊
Organizations should carefully evaluate their proj-
ect requirements; the appropriateness of CGMP in
a “fit for use” context, and should document the re-
search results so that required CGMP can be clearly
defined.
◊
The requirements definition should include, at a
minimum:
Consideration of technical requirements,
Schedule and method of delivery,
Acceptable warranty and/or licensing restric-
tions,
Documentation expected to be provided by the
CGMP provider, including specifications, instruc-
tion manuals and metadata
