Remote Sensing And Image Interpretation follows each other. After the image ry is obtained through Remote Sensing equipments, it is processed to extract information about the shapes, amount, size, location of the feature or object or phenomenon on the earth surface.
Remote Sensing :
The method of obtaining information about the object without coming in contact physically with the object with the help of camera mounted on air-borne platforms is called Remote Sensing. A ray called electromagnetic spectrum is emitted, or reflected back from the object which records the Imagery on the scanners through the passive or active sensors used in the camera. Electromagnetic spectrum can be classified into various bands ranging from wavelengths 0.30 mm to 1m. These bands are absorbed differentially by different features and as a result they emit differentially. These spectral variation produces visual effect within the visible region of spectrum called COLOUR. Image Interpretation is done on the basis of these colors and the tonal variation presented by these colors.
Remote Sensing And Image Interpretation : Information extraction
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Types |
Example |
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Classification |
Land Cover, Vegetation |
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Change Detection |
Change in Land Cover |
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Detecting Physical Quality |
Atmosphere, Soil, Geology, Temperature, Water Bodies |
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Finding Indices |
Vegetation and Turbidity index |
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Identifying Specific Features |
Disaster Identification, Finding Out Archaeological Sites. |
Remote Sensing And Image Interpretation : Image Interpretation is of three types-
It involves identification of different features, their shapes, sizes, color, texture, tone, pattern of distribution, their relationship on the earth surface.
This involves measuring distance, density, height, temperature, length, width by using the data available for reference.
This is an effort made by the analyst to detect the relationship between the information available in interpretation and the real status of the feature. This also involves image evaluation. |
Remote Sensing And Image Interpretation :
Tool: Stereoscope
Viewing Image s is done by a pair of stereoscope. Left eye is used to look upon the left Image and right eye is used to look upon the right Image. Principal points of the right and left Images should be marked and must be aligned along a straight line before viewing. A 3D view of the features is obtained through the stereoscope.
Remote Sensing And Image Interpretation : Interpretation Characteristics
- Size : This aspect helps to identify the object for example difference in size of water bodies will help to identify lakes and tanks.
- Shape: Shape helps to detect and identify features like river and sea.
- Shadow: Shadow provides with information about heights for example tower heights.
- Tone: An object can be identified by its tone based upon its reflectance.
- Color: Red patches will indicate vegetation whereas grey patches will indicate settlement.
- Texture: Repetitive small patterns like homogeneous grasslands can be identified through texture.
- Pattern: Regular patterns like row of houses can provide valuable information.
- Relationships between the objects: A detail analysis of the above aspects will provide information about the relationships among the objects as well as with the earth.
Remote Sensing And Image Interpretation truly follows each other for a successful processing of the imagery.
GPS Survey Equipment