Imagery Analysis is defined as interpreting an image which is acquired through aerial photography or satellites. In other words Imagery Analysis is called photo interpretation. Imagery Analysis brings out the necessary information from the Imagery .
Imagery Analysis Tools:
• One Band Imagery Analysis Tool: Interpretation of only one electromagmetic spectrum band found in the image is done with this Imagery Analysis tool. There is a selection box of band which permits the user to select any one band. The user then chooses a color to apply to the band and adjust the Analysis Area Pixel Width value and selects Digital Centre of Interest on the map to analyze the chosen area.
• Three Band Imagery Analysis Tool: Particular bands are assigned to the three basic colors:red, blue and green. If any one of the three color is present in the image, then that particular band is represented 100% for that pixel. An optical display of the components of the three chosen bands found in any pixel position is provided by this tool of Imagery Analysis .
• Two-Band Ratio Analysis : This tool of Imagery Analysis permits the user to create band-ratio analysis image. The difference between the two areas of electromagnetic spectrum over the analysis region is displayed by the ratio of two bands. This tool of Imagery Analysis has two advantages – minimizes the shadow effect and can easily differentiate features like minerals, water clarity, depth of water and vegetation.
• False Color Composit Analysis : In this tool of Imagery Analysis ratio images are assigned to the three base colors and a red, green, blue image is generated. Combining band ratios which detect particular characteristics into one image will help to transmit a lot of information in that particular image.
Interdisciplinary Imagery Analysis:
This type of Imagery Analysis requires analysts from different fields of study like geology, botany, geography, biology, pedology, archaeology, economics, architecture and other subsequent fields. They determines the social, physical, economical, biological features of a place. They not only determine the different characteristiks but also explains them, interprets the features, finds the relation between the features and forecasts the reaction of the features towards the future change of environment. Change in the land use or resource reserves can also be interpreted through Imagery Analysis . Depending on the purpose of the Imagery Analysis , the experts from different fields are chosen.
Use of Imagery Analysis :
• Select sites for construction works like bridges, roads, high rise buildings, dams and barrages etc. For example the areas which do not have a stable geologic structure are not suitable for building large dams.
• Studies the hydrology of a place which may predict future cultivation or construction in that area. For example low water level in a fertile area will suggest irrigation to the farmers of that area.
• Analyzes the soil of an area which may give insight to development of agriculture or constructional work in that place. For example an area having poor soils may be chosen for factory site.
• Analyzes the resource reserves in an area and helps the government to plan for future conservation.
Thus it can be said that Imagery Analysis is an important tool used for advancement of a nation.
Remote Sensing Applications