Processing Levels
Radiometric Correction Method - Options are CPF or IC
- CPF: The Calibration Parameter File (CPF) Radiometeric Correction method is developed by the Image Assessment System staff based on spacecraft measurements in three major categories: geometric parameters, radiometric parameters, or artifact removal parameters.
Band Combination - Options are 1, 2, 3, 4, 5, 6l, 6h, 7, 8
- Landsat 7 ETM+ acquires spectral coverage in eight channels and/or bands.
Image Orientation - Options are NUP or NOM
- NUP = The image data is geographically rotated to a North Up orientation (map).
- NOM = Nominal system (path) orientation applied to the image data.
Resampling Method - Options are CC, NN and MTF
- CC - Cubic Convolution = Uses a weighted average of values within a neighborhood of adjacent pixels. Images generally are much more attractive than other resampling methods, but the data are altered much more drastically.
- NN - Nearest Neighbor = Assigns each "corrected" pixel the value from the nearest "uncorrected" pixel. Original data values are preserved unaltered in the image, yet noticeable positional errors, which can be especially severe in easily recognizable linear features where the realignment of pixels is obvious.
- MTF = Modulation Transfer Function pixel resampling method.
Scan Gap Interpolation (SLC-OFF ONLY) - Options are 0 - 15 pixels
- The number of pixel values that are interpolated into the scan gap region of an SLC-off scene during Level 1G processing. The default value for standard Level 1G processing of SLC-off data is 2 pixels. For more information: SLC-off scan gap interpolation.
Grid Cell Size for the Pan Band (8) - Options are 14.25 to 60.0
- A grid cell size of 14.250 through 60.000 meters, in increments of .001 meters used by the Level 1 Product Generation System (LPGS) in creating image for pan band.
Grid Cell Size for the Reflective Bands (1-5,7) -
Options are 25.0 to 60.0
- A grid cell size of 25.000 through 60.000 meters, in increments of .001 meters used by the LPGS in creating image for pan band.
Grid Cell Size for the Thermal Bands (6L, 6H) - Options are 25.0 to 60.0
- A grid cell size of 25.000 through 60.000 meters, in increments of .001 meters used by the LPGS in creating image for pan band.
Zone Number - Options are -60 to 60
- A grid system based on the transverse mercator projection, applied between latitudes 84 degrees north and 84 degrees south on the Earth's surface.
Scale Factor at Projection Center - Options are 0.0 to 2.0
- Scale factor at the center of the map projection. A multiplier for reducing a distance obtained from a map by computation or scaling to the actual distance at the projection origin. Scale Factor at Projection Origin > 0.0
Scale Factor of the Central Meridian - Options are 0.0 to 2.0
- A multiplier for reducing a distance obtained from a map by computation or scaling to the actual distance along the central meridian. Scale Factor at Central Meridian > 0.0
Latitude of First Standard Parallel - Options are -90.0 to 90.0
- Line of constant latitude at which the surface of the Earth and the plane or developed surface intersect.
Latitude of Second Standard Parallel - Options are -90.0 to 90.0
- Line of constant latitude at which the surface of the Earth and the plane or developed surface intersect.
Longitude of Projection Origin (Central Meridian) - Options are -180.0 to +180.0
- The line of longitude at the center of a map projection generally used as the basis for constructing the projection.
Latitude of Projection Origin - Options are -90.0 to 90.0
- Latitude chosen as the origin of rectangular coordinates for a map projection.
False Easting - Options are -1.0 X 10(8) to +1.0 X 10(8)
- False Easting (FE) is the offset of the central meridian, entered in meters. The default results in no offset. False Easting is in the same units as the semi-major axis (radius of the equatorial axis of the ellipsoid). The value added to all "x" values in the rectangular coordinates for a map projection. This value frequently is assigned to eliminate negative numbers.
False Northing - Options are -1.0 X 10(8) to +1.0 X 10(8)
- False Northing (FN) in the same units as the semi-major axis (radius of the equatorial axis of the ellipsoid). The value added to all "y" values in the rectangular coordinates for a map projection. This value frequently is assigned to eliminate negative numbers.
Units for False Easting and Northing - Default Option is Meters
- Typically meters or feet are used as units for False Easting and Northing. Meters only are used for Level1 products.
Longitude of Center Line's First Point - Options are -180.0 to +180.0
- Longitude of first point defining central geodetic line of projection.
Latitude of Center Line's First Point - Options are -90.0 to 90.0
- Latitude of first point defining central geodetic line of projection.
Longitude of Center Line's Second Point - Options are -180.0 to +180.0
- Longitude of second point defining central geodetic line of projection.
Latitude of Center Line's Second Point - Options are -90.0 to 90.0
- Latitude of second point defining central geodetic line of projection.
Azimuth of Inital Line at Projection Origin - Options are -180.0 to +180.0
- Method used to describe the line along which an oblique mercator map projection is centered using the map projection origin and an azimuth. Used for Oblique Mercator Type B map projection.
Lambert Conformal Conic-Example
- Primarily used for equal-angle maps of regions with a predominant east/west extent. The following characteristics are applicable to the Lambert Conformal Conic projection.
- Conic.
- Conformal.
- Parallels are unequally spaced arcs of concentric circles, more closely spaced near the center of the map.
- Meridians are equally spaced radii of the same circles, cutting the parallels at right angles.
- Scale is true along two standard parallels.
- Pole in same hemisphere as standard parallels is a point; other pole is at infinity.
Oblique Mercator Type A - Example
- Oblique Mercator (Hotine) A. Used primarily for mapping regions with an extent in the oblique direction and was used (before SOM) for mapping Landsat data. This projection uses two points that are on the central line and are near the edges of the region. The following characteristics are applicable to the Oblique Mercator (Hotine) A projection.
- Cylindrical (oblique).
- Conformal.
- Parallels are complex curves.
- Meridians are complex curves except for two meridians which are 180 degrees apart and are straight lines.
- Scale becomes infinite 90 degrees from the central line.
Oblique Mercator Type B
- Oblique Mercator (Hotine) B. Used primarily for mapping regions with an extent in the oblique direction and was used (before SOM) for mapping Landsat data. This projection uses a central point and an azimuth that passes through the point as the central line. The following characteristics are applicable to the Oblique Mercator (Hotine) B projection.
- Cylindrical(oblique)
- Conformal
- Parallels are complex curves.
- Meridians are complex curves except for two meridians which are 180 degrees apart and are straight lines.
- Scale becomes infinite 90 degrees from the central line.
Polar Stereographic - Example
- Primarily used for the mapping of the polar areas of the Earth, Moon, and other planets. The following characteristics are applicable to the Polar Stereographic projection.
- Azimuthal.
- Conformal.
- Parallels are shown as arcs of circles.
- All meridians are straight lines.
- Scale increases away from the center of the projection.
- Directions from the center of projection are true.
Polyconic - Example
- Used to provide a low-distortion mapping of local areas. This projection is rarely used today. The following characteristics are applicable to the Polyconic projection.
- Conic.
- Neither conformal nor equal-area.
- Parallels (except equator) are arcs of circles.
- Meridians are complex curves (Central meridian and equator are straight lines).
- Scale is true along each parallel and central meridian.
- Free of distortion only along central meridian.
Space Oblique Mercator -Example
- Used for mapping imagery from Landsat and other satellites with nearly circular orbits. The following characteristics are applicable to the Space Oblique Mercator projection.
- Modified cylindrical.
- Basically conformal.
- Parallels are curved lines.
- Meridians are curved lines except at each polar approach.
- Scale is true along ground track of satellite.
Transverse Mercator
- Primarily used for regions which are predominantly extending north and south. The following characteristics are applicable to the Transverse Mercator projection.
- Cylindrical (transverse).
- Conformal.
- Parallels are complex curves. The equator is a straight line.
- Each meridian that is 90 degrees from the central meridian is a straight line. All other meridians are complex curves.
- Scale is true along the central meridian or along two straight lines equidistant from and parallel to central meridian. Scale becomes infinite 90 degrees from central meridian.
Universal Transverse Mercator - Example
- An ellipsoidal Transverse Mercator projection to which specific parameters have been applied. The earth is divided into 60 zones which are 6 degrees wide.
Ground Control Point software automatically adds a false northing of 10,000,000 meters if the first coordinate is south of the equator. Problems may occur when working around the equator.
When working in the Southern Hemisphere, enter a negative zone code.
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