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  1. what is remote sensing
    any technique employed that acquires specific data regarding a specific object without coming into contact with that object
  2. what is radiometric resolution
    • the ability of a sensor to interpet grey value
    • the bit number e.g. 8 bit has 2^8 color values
  3. remote sensing systems record___________
    electromagnetic energy
  4. The location and wavelength of the _______________ that is used is dictated by the sensor usedand will determine the nature of the informationavailable from the data.
    electromagnetic spectrum
  5. what are the two primary types of systems
    active and passive
  6. active remote sensing 3 points 3 examples
    generate own energy

    ability to emit and record return signals

    not restricted to periods of time when outside energy is availible

    Lidar radar and sonar
  7. passive remote sensing 3
    rely on outside energy

    sun is main source of energy

    typically resemebles what we see in the vissible spectrum
  8. what defines the visible spectrum
    400-700nm
  9. what is the main goal of remote sensing
    resource managment and identification
  10. what are the three multi dimensions of remote sensing
    • temporal
    • spatial
    • spectral
  11. what are the main issues with remote sensing data ___________ vs ___________
    detection vs resolution
  12. what are teh 5 steps of the photo interpertive model
    • detection - find it
    • analysis-7 elements of phot id
    • deduction- who the fuck knows
    • classification- give it a name
    • theorization-make up some bullshit
  13. what are the seven elements of phot interpertation
    • size
    • shape
    • shadow
    • tone
    • texture
    • time
    • patern
    • association

    ssstttpa
  14. photo id element shape
    geometric charecteristics

    narual orangic shapes

    linear manmade shapes
  15. phot element size
    absolute with a measurement or relative
  16. phot id elemnt tone/color
    • related to reflectance
    • a fucntion of surface filter and film
  17. phot id texture
    visual impresion of coarseness vs smothness
  18. phot id element shadow
    provides info on heigh but may mask features
  19. photo id association
    associating one object with another, a long linear feature by a railway is likely train tracks
  20. phot id element time
  21. look at temporal photos to see change over time
  22. increasing angular field of view (AFOV) does two things
    increases the ground coverage or allows lower flying height
  23. small focal lenght =_________ angle field of view
    smaller focal lenght has a larger angel thus can see more
  24. what are fiducial marks?
    registration marks on edges of air photos
  25. describe the three types of centers in photos
    Principal point - exact geometric center

    Nadir - directly under the focal plane

    Isocenter - halfway between the two
  26. what is relief displacement
    trhe displacment of a 3d object on a photo due to changes in height
  27. what is paralax
    the apparent distortion of an object caused by movement of the observer relative to that object
  28. what are the three components to color
    hue- dominant wave lenght i.e. rgb

    chroma-intensity of the color

    value- lightness or brightness
  29. primary colors additive vs subtractive mixing
    additive - what we see RGB

    subtractive how ink works MYC
  30. fast vs slow films

    _1__=_2___=__3__=__4__=__5_
    fast film = less light = high iso = large xstal=lower resolution
  31. why do we use filters in photography
    to absorb or transmit specifi wavelenghts
  32. what does a clear glass filter remove
    UV radiaition and lens protection
  33. what doe we use a blue filter for
    removes short wavelenght atmispheric noise
  34. what does an IR filter do
    removes everything EXCPET the IR
  35. resolution is _________ to the grain size of the film
    inversely proportional
  36. what is resolution
    the ability of the film or lens to image spatial DETAILS

    do not confuse resolution with detection
  37. what is the overlap and side lap for air pjotos
    60% overlap and 25% side lap
  38. what is max tilt for an air photo
    2-3 deg
  39. what is the diference between instananeous and angular field of views

    afov vs ifov
    ifov- smalles unit recodable by the senser

    afov is the width of how many small units can be seen
  40. optical sensors cover the __________nm range between_________  (names of wavelenghts)
    400-2500

    Visible and reflected IR
  41. microwaves fall in the ____ portion while IR, Vis and UV fall in the _____________ 

    scales of the wavelenghts
    microwaves are cm

    everything else is nm
  42. what are the four types of optical sensors
    • electromechanical
    • pushbroom
    • spectrometers
    • imaging spectrometers
  43. describe electromechanical scanner (4)
    • detector:passive-discrete 
    • AFOV-rotating mirrior
    • IFOV - sampling rate
    • sensor uses optical grading
  44. describe push broom scanner (4)
    • detector: pasive-discrete linear
    • large spatial coverage
    • CCD- charged coupled devices
    • multiple arrays record different EMS=multispectral image
  45. what is the elctomechanical scanner we foccused on
    Landsat
  46. 2 examples of pushbroom sensors
    AISA and CASI
  47. describe spectrometer sensor (4)
    • NOT imagage data
    • ground based
    • determines specifics features like leaf reflectance
    • *smallest spatial coverage
  48. describe an imaging spectrometer
    • combines pushbroom, electromechanical and spectrometer
    • builds an image cube
    • x and y are spatial
    • z is spectral
  49. three factors to discussing image processing and analysis systems
    radiometric resolution

    hardware

    software
  50. what is a DN value
    DN value or pixle value digitial number is related to the radiometric resolution

    its the amount of EM detected
  51. real vs integer storage
    8 bit is integer (whole numbers)

    32 bit is real (fractions and decimals)
  52. advantages to real vs integer storage
    real has finer definition and mathamatical manipulations
  53. what are the basic statistics for image processing
    image description-mean,median, std

    enhancement manipulation - 

    image analysis and mdeling

    histograms
  54. problems with data correlation (2)
    something about more data doesent increase understanding

    some bullshit about regression techniques
  55. blue vs red light
    blue = short wave hig freq

    red=long wave low freq
  56. 7 wave types from longest to shortest wave
    • radiowave
    • microwave
    • IR
    • visible
    • UV
    • x ray
    • gamma ray
  57. what is a black body
    an object that abosrbs all incoming radiation and emits all energy at full effiency for all wave lenghts
  58. black body radiation is goverend by ____law(s)
    • plancks law
    • weins displacement law
  59. what is plancks law
    black body radiation

    describes the distribution of brightness in the spectrum of a black body
  60. what is wiens displacement law
    determines which wavelenght yields the most radiation

    i.e. the cooler the body the longer the dominant wave lenght
  61. significance of wiens/plancks laws (3)
    the longer the wavelenght the lower its energy contenet

    the hotter the object the more energy it radiates and the shorter the wave lenght

    the cooler the object the less energy it radiates and the longer its dominant wavelenght is
  62. 3 paths of energy and matter interact
    • irradiance
    • radiance
    • reflectance
  63. what is irradiance
    EM flux Incident on the surface
  64. what is radiance
    flux leaving a source
  65. what is reflectance
    reflectance =  radiance/incidance

    its a ratio!
  66. what 4 things happen to energy as they interact with matter
    • Transmision/refraction
    • absorption/re-emited
    • relection
    • scattered
  67. what are the three types of scattering
    • ralyiegh
    • MIE
    • nn-selective
  68. two type of reflecters
    difuse lambertian- rough uniform all directions

    specular - reflactance = incidence concetrated reflection
  69. one can use the ___________ of an object to determine its classification in an image
    spectral signature
  70. we correct images for three reasons
    • radiometric
    • atmospheric
    • geometric
  71. radiometric corrections - 4
    • instrument noise
    • striping
    • dropline
    • bit errors
  72. amospheric corrections - 4
    • atmospheric noise/disturbance
    • bidirectional reflectance
    • slope correction
    • path radiance
  73. radiometric corrections insturment/dark object
    insturments make white noise

    take a black picture to reduce noise
  74. radiometric destriping
    calibration of the detectors with each other on each band
  75. what is the fourier transform
    an alternative destripping routine which removes repetitive noise in any direction
  76. what is drop line correction
    random lines dont show up do to sensor error and the cmputer estimates based of the line above and below the missing piece
  77. what are random bit errors
    where random pixels are individually missing
  78. what two things do atmospheric corrections remove
    • different illumination effects
    • changes in atmospheric cmposition
  79. energy is _____ as it travels through the atmosphere
    attenuated
  80. why do we convert from radiance to reflectence (radiometric atmospheric stuff)
    it removes the effects of atmosphere so data from diffrent temporals works
  81. what are three ways to convert radiance to reflectance
    • radiative transfer model (physics based)
    • empiracl approach (statistical)
    • mechanical approaches
  82. what is bi directional reflectance why care
    • surfaces are anisotropic
    • important when working with high spatial resolution and temporal data
  83. what is path radiance
    atmospheric scattering effect on the total radiance recorded by the sensor
  84. what are paremetric statistics
    statistics that make inferences about the parameters
  85. what is the relation od standards and normal deviation
    • 68% is under 1 deviation
    • 95 under 2 and 99.7 under 3
  86. what is standard deviation
    the square root of the datas varriance

    it brings the value into the same range as the data for comparison
  87. why use the coeficient of variance
    allows us to compare dispersion of two or more samples of different magnitudes
  88. to compare two or more variables use_________
    • covariance
    • deals with corelation and regresssion
  89. correlation tests the __________
    interdependence of two or more variables
  90. regression describes_________
    the dependence of of one or more variable
  91. what is image skew
    systematic distortions due to angular velocity of earth as sensor is scanning
  92. two types of geometric conversion
    image to image

    image to map
  93. what are the two steps to geometric corrections
    rectification-linking of images

    resampling-transfer from slave to master image
  94. what are ground control points
    points that are used to link the master and slave images, must be indentifiable in each
  95. how do we check ground control points
    root mean square RMS
  96. what are the three ways of generating a new image when rectificationing
    • conformal transformation (x only)
    • affine trasformation (first order) (x and Y)
    • higher order polynomial transformation
  97. what are the three methods to image resampling
    nearest neighbor (true no change 0 order)

    bilinear (1st order average of sourounding)

    cubic (same as bilinear but larger area)
  98. 4 classes of image enhancement
    • lowradiance low albedo
    • high radiance high albedo
    • low contrast
    • highcontrast
  99. what is contrast stretching
    expanding original brightness values to increase contrast and interpability
  100. contrast stretching linear
    increases the contrast while preserving the original radiance
  101. contrast stretching nonlinear
    enhances certain portions of the histogram
  102. what is spacial filtering
    the extraction of information in the spatial rather than spectoral domain
  103. what is spatial frequency
    the number of times a certain pixel occurs within a predefined area within an image
  104. what is a low pass filter for
    removes the imagery with high spatial frequency - it smoothes the image
  105. what is a high pass filter for
    enhances abrut changes  in data with in the image - highlights sharp linear features
  106. what is fast fourier transform FFT
    be=reaks image into frequency and direction components

    can be high pass or low pass
  107. edge detetection features are either____or____
    nondirectional or directional (can highlight features in a given direction)
  108. what is a laplacian filter
    nondirectional filter that highlights maximum peak values
  109. what is the compas gradient filter
    enhances linear features given a specific azimuth
  110. why do we use band ratios
    to enhance or amplify a signal
  111. three functions of the PCA primary component analysis
    reduce the dimensionality of the data set

    decorelate the data

    to choose the most appropriate data set for use in applications
  112. what is the key goal of classification
    simplification making the image easier to interput
  113. 4 steps to image classification
    • slelect training areas
    • build spectral signatures
    • classification
    • accuracy assesment
  114. what are the two types of classification
    supervised-user determined boundries

    unsupervised- automatic class boundries
  115. three parametric classification algorithms
    • minimum distance to mean
    • parellepipid
    • maximum likihood
  116. 3 non paremetric classifications
    • spectral mixture anaylsis
    • spectral angel mapper
    • support vector
  117. the minimum distance to mean is associated with the or relies on the
    euclidean straight line methods
  118. the parelel pipid methods uses a _______for classification
    boxed values of max and min
  119. how does the maximum likihood classifier work
    looks at variance and covariance and puts the pixel where it most likely goes
  120. spectral mixture anaylisis SMA does what
    decomposes a pixel into its proportions
  121. Single angel mapper classification uses_____
    the sahpe of a spectrum
  122. all classifications must include an
    accuracy report
  123. 5 sampling methods for accuracy assesment
    • systamatic
    • stratified
    • random
    • stratified random
    • cluster
  124. what is the kappa koeficient
    a normalization procedure to standardize error matricies so they can be compared to one antother

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speny
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Updated:
2015-12-14 20:33:10
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