Transcription of Principals and Elements of Image Interpretation
1 1 Principals and Elements of Image Interpretation2 Fundamentals of Photographic Interpretation Observation and inference depend on interpreter s training, experience, bias, natural visual and analytical abilities. Human visual or manual Interpretation is still a dominant approach to day-to-day applications of remote sensing. Observation and understanding of the basic Elements of photo Interpretation are photo/ Image Interpretation ? Aerial/Regional Perspective: Examination of the Earth from an aerial perspective allows us to identify objects, patterns, and man-land interrelationships. Remotely sensed Image provides spatial terrain photo/ Image Interpretation ? The ability to obtain a historical Image record to document change: The photographs or images are valuable historical records of the spatial distribution of natural and man-made phenomena. The study of change increases our understanding about the natural and human-induced processes in the photo/ Image Interpretation ?
2 Three-Dimensional Depth Perception: We can obtain a 3-dimensional view of the terrain by viewing the two images of the terrain from two slightly different vantage points at the same time. Stereoscopic analysis process provides us the information of object s height, depth, and Information from DataHeads-up digitizingDigital Image classifications Unsupervised Supervised5 Digital Image Classification?Information Extraction from Pixels6 Principals and Elements of Visual Image InterpretationFundamentals of Photographic InterpretationPhoto Interpretation :The examination of aerial photographs/images for the purpose of identifying objects and judging their & Inference:Observation provides the raw data for Interpretation . Inference is the logical process by which observation and Interpretation are Interpretation Observation - InferenceWhere to draw the line?8 Image Interpretation for Land Use MappingUSGS Land Use and Land Cover Classification SystemAnderson, J.
3 R., E. E. Hardy, and J. T. Roach, 1976. A Land Use and Land Cover Classification System for Use with Remote Sensor Data, Washington, DC: Geological Survey Profession Paper 964, 28 pp. 9 USGS Land Use and Land Cover Classification SystemLevel I1 urban or built-up landLevel II11 Residential12 Commercial and Services13 Industrial14 Transportation, Communications, and Utilities15 Industrial and Commercial Complexes16 Mixed urban or Built-up land17 Other urban or Built-up LandUSGS Land Use and Land Cover Classification SystemLevel I2 Agricultural landLevel II21 Cropland and pasture22 Orchards, groves, vineyards, nurseries, and ornamental horticultural areas23 Confined feeding operations24 Other agricultural land10 USGS Land Use and Land Cover Classification SystemLevel I3 Rangeland4 Forest landLevel II31 Herbaceous rangeland32 Shrub and brush rangeland33 Mixed rangeland41 Deciduous forest land42 Evergreen forest land43 Mixed forest landUSGS Land Use and Land Cover Classification SystemLevel I5 Water6 WetlandLevel II51 Streams and canals52 Lakes53 Reservoirs54 Bays and estuaries61 Forested wetland62 Nonforested wetland11 USGS Land Use and Land Cover Classification SystemLevel I7 Barren landLevel II71 Dry salt flats72 Beaches73 Sandy areas other than beaches74 Bare exposed rock75 Strip mines, Quarries, and gravel pits76 Transitional areas77 Mixed barren landExample of Sub-categorization of Residential Land (Level III)Level ILevel IILevel III1.
4 urban or Built-up Residential Single-family Multi-family Group Residential Mobile Home Transient Other12 Representative Image Interpretation Formats for Various Land Use/Land Cover Classification LevelsLand Use/Land Cover Classification LevelRepresentative Format for Image InterpretationILow to moderate resolution satellite data ( , Landsat MSS)IISmall-scale aerial photographs; moderate resolution satellite data ( , Landsat TM)IIIM edium-scale aerial photographs; high resolution satellite data ( , IKONOS)IVLarge-scale aerial photographs(USGS Level II)13(USGS Level I)14 Elements of Image Interpretation x,yLocation Size Shape Shadow Tone/Color Texture Pattern Height/Depth Site (elevation, slope, aspect) Situation AssociationElements of Image InterpretationElementCommon Adjectives(Quantitative and qualitative)x,ylocationx,ycoordinate: longitude and latitude or meters easting and northing in a UTM map gridSizeLength, width, perimeter, area (m2)small, medium (intermediate), largeShapeAn object s geometric characteristics: linear, curvilinear, circular, elliptical, radial, square, rectangular, triangular, hexagonal, pentagonal, star, amorphous, of Image InterpretationElementCommon Adjectives(Quantitative and qualitative)ShadowCaused by solar illumination from the sideTone/colorGray tone: light (bright), intermediate (gray), dark (black)Color.
5 HIS = intensity, hue (color), saturation; RGB = red, green, blue; MunselTextureCharacteristic placement of objects on the ground: systematic, random, linear, curvilinear, rectangular, circular, arrangement of objects on the ground: systematic, random, linear, curvilinear, rectangular, circular, of Image InterpretationElementCommon Adjectives(Quantitative and qualitative)Height/depthVolume/ slope/aspectz-elevation (height), depth (bathymetry), volume (m3), slope o, aspect oSite/situation/associationSite: elevation, slope, aspect, exposure, adjacency to water, transportation, utilitiesSituation: objects are placed in a particular order or orientation relative to one anotherAssociation: related phenomena are usually present16 The sizeof an object is one of the most distinguishing characteristics and one of the most important Elements of Image natural and man-made features on the ground have very unique shapesthat can be referenced in photo and Image TonePseudo Color ImageThe electromagnetic radiation (EMR) recorded byremote sensing system can be displayed in shades of gray ranging from black to white may use additive color-combining techniques to create colorcomposite the characteristic placement and arrangement of repetitions of tones or color in an the spatial arrangement of objects in the texture and pattern are scale shadowin the Image provides real clue to an object s identification, , ability to visually appreciate or measure the height (elevation) or depth (bathymetry)
6 Of an object or landform is one of the most diagnostic Elements of Image , situation, and associationcharacteristics are very important when trying to identify an object or activity. They are always used :- physical (elevation, slope, aspect, type of surface cover) - socioeconomic (value of the land, adjacency to water)Situation:How objects are organized and oriented relative to one :When you find a certain activity or phenomena, you almost invariably encounter related or associated features or activities. reviewRIGIS land use/land cover map data19 Land use/land cover from 1987 aerial photography coded to Anderson modified level 3 with acre minimum polygon resolution. 1995 Land use/land cover updated using 1987 land use as a Land Use Land Cover Map DataWhere to draw the line?20 Delineation of polygonsand placement of labelsA: Error in matching boundariesB: Error in labeling parcelsAB21 The Photo-OverlayLeft:aerial photograph Right:land cover boundaries as interpreted from the photographs; numbers corresponded to Anderson Level II classification system.
7 The delineation of a land use polygon includes the entire area devoted to a particular use. In this example the entire area inside the boundaries of an airfield is represented on the land use map as a single polygon, even though it is composed of several recognizable components. 2223 Land-Cover Map Designates the visible evidence of land use features. Directly observable physical or biophysical cover on the earth s surface CONCRETELand-Use Map The use of land by humans, usually with emphasis on the functional role of land in economic activities Land use forms an abstraction, not always directly observable even by a closest inspection ABSTRACTThe definition establishes a direct link between land cover and the actions of people in their Example of Land-Use Map vs. Extracted Impervious Surface AreasOpenlandUrban GrassWaterWetlandForest/WoodlandBrushlan dUrbanPasture/CroplandOpenlandUrban GrassWaterWetlandForest/WoodlandBrushlan dUrbanPasture/CroplandQuonset StateAirportNarragansett BayAn Example of Land-Use Map vs.
8 Extracted Impervious Surface Areas25 Use of color as symbols for land use classes by USGS system Level ICategorySymbolColorUrban/Built-up Land1 RedAgricultural Land2 Light BrownRangeland3 Light OrangeForest Land4 GreenWater5 Dark BlueWetland6 Light BlueBarren Land7 GrayTundra8 Green-GrayPerennial Snow or Ice9 White26 From oblique aerial photograph to measurable information???
