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How Can You Interpret Objects in an Aerial Image?
was in a big city. Looking closely, you can make out a different colored object
(the light blue) on the main complex and determine that it’s a swimming
pool, further narrowing down the building to some sort of hotel or resort.
Although the height of the tower on the right-hand side of the image isn’t
really discernible (since the image was taken looking down onto the tower
itself), the huge shadow being cast by the tower (stretching right to left) is
visible. Based on the length of the shadow (and the shape of the shadow
being cast), you could determine that object was a tower (or a similar very
large, very tall object). Putting all of these clues together (city-block-sized
hotel/resort in a big city with a massive tower in front of it), you would be
able to use some outside information (like examining some travel books or a
short Web search) to quickly determine that the image is of the Stratosphere
Hotel in Las Vegas.
When you try to interpret features in an aerial photo or other remotely
sensed satellite image (for instance, objects in developed areas or physical
features on the landscape), you act like a detective searching for clues in
the image to figure out what you’re really looking at. Like in the Stratosphere Hotel example, clues like the size and shape of objects or the shadows being cast aid in determining what you’re really looking at. Visual
image interpretation is the activity of identifying features in an aerial
(or other remotely sensed) image based on several distinct elements as
follows:
a Pattern: This is the physical arrangement of objects in an image. The pattern of how objects are lined up (or disarrayed) will often aid in interpreting an image. A large series of cars uniformly set up in a parking lot
around a relatively small building would likely be a clue indicating a car
dealership rather than another type of shopping area. Evenly spaced airplanes or jets may be a clue to identifying a military base, while a haphazard arrangement of aircraft could indicate a group of statics on display at
an aircraft or military museum.
FIGURE 9.11 The
Stratosphere Hotel and
Casino in Las Vegas,
Nevada: (a) an overhead
aerial view of the building
and (b) an oblique image
showing the tower and
the hotel layout. (Sources:
(a) Bing Map © 2011
Microsoft Corporation Image
courtesy of the Nevada
State Mapping Advistory
Committee. Esri® ArcGIS
ArcExplorer graphical user
interface Copyright © Esri.
(b) Tim Jarrett/Wikipedia)
visual image
interpretation the
process of discerning
information to identify
objects in an aerial (or
other remotely sensed)
image.
pattern the
arrangement of
objects in an image.
An element of image
interpretation.
(a)
(b)
How Can You Interpret Objects in an Aerial Image?
was in a big city. Looking closely, you can make out a different colored object
(the light blue) on the main complex and determine that it’s a swimming
pool, further narrowing down the building to some sort of hotel or resort.
Although the height of the tower on the right-hand side of the image isn’t
really discernible (since the image was taken looking down onto the tower
itself), the huge shadow being cast by the tower (stretching right to left) is
visible. Based on the length of the shadow (and the shape of the shadow
being cast), you could determine that object was a tower (or a similar very
large, very tall object). Putting all of these clues together (city-block-sized
hotel/resort in a big city with a massive tower in front of it), you would be
able to use some outside information (like examining some travel books or a
short Web search) to quickly determine that the image is of the Stratosphere
Hotel in Las Vegas.
When you try to interpret features in an aerial photo or other remotely
sensed satellite image (for instance, objects in developed areas or physical
features on the landscape), you act like a detective searching for clues in
the image to figure out what you’re really looking at. Like in the Stratosphere Hotel example, clues like the size and shape of objects or the shadows being cast aid in determining what you’re really looking at. Visual
image interpretation is the activity of identifying features in an aerial
(or other remotely sensed) image based on several distinct elements as
follows:
a Pattern: This is the physical arrangement of objects in an image. The pattern of how objects are lined up (or disarrayed) will often aid in interpreting an image. A large series of cars uniformly set up in a parking lot
around a relatively small building would likely be a clue indicating a car
dealership rather than another type of shopping area. Evenly spaced airplanes or jets may be a clue to identifying a military base, while a haphazard arrangement of aircraft could indicate a group of statics on display at
an aircraft or military museum.
FIGURE 9.11 The
Stratosphere Hotel and
Casino in Las Vegas,
Nevada: (a) an overhead
aerial view of the building
and (b) an oblique image
showing the tower and
the hotel layout. (Sources:
(a) Bing Map © 2011
Microsoft Corporation Image
courtesy of the Nevada
State Mapping Advistory
Committee. Esri® ArcGIS
ArcExplorer graphical user
interface Copyright © Esri.
(b) Tim Jarrett/Wikipedia)
visual image
interpretation the
process of discerning
information to identify
objects in an aerial (or
other remotely sensed)
image.
pattern the
arrangement of
objects in an image.
An element of image
interpretation.
(a)
(b)