Contains classes and attributes used to describe cartographic products. This information is largely adapted from the FGDC "Content Standard for Digital Geospatial Metadata", with extensions (changes/ additions) to satisfy planetary requirements. ## CHANGE LOG ## 1.9.0.0 - Upgraded to v1900 of the IM - Created new Map_Projection_Lander class with associated map projections and attributes - New pixel_scale attribute that defines a pixel scale not x/y aligned - Change units for pixel_scale_x/y to Units_of_Pixel_Scale_Map - Change units for pixel_resolution_x/y to Units_of_Pixel_Resolution_Map - Change local_georeference_information to optional in the case where Map_Projection_Lander is specified. - Created Local_child_check rule to check this - Change Spatial_Domain to optional in the case where Map_Projection_Lander is specified since domain is the horizon - Created spatial_domain_or_lander_check rule to check this The Bounding_Coordinates class defines the limits of coverage of a set of data expressed by latitude and longitude values in the order western-most, eastern-most, northern-most, and southern-most. The Camera_Model_Offset class specifies the location of the image origin with respect to the camera model's origin. For CAHV/CAHVOR models, this origin is not the center of the camera, but is the upper-left corner of the "standard"-size image, which is encoded in the CAHV vectors. Applies to the Perspective lander map projection. The Cartography class provides a description of how a 3D sphere, spheroid, or elliptical spheroid or the celestial sphere is mapped onto a plane. The Coordinate_Representation class provides the method of encoding the position of a point by measuring its distance from perpendicular reference axes (the "coordinate pair" and "row and column" methods). TBD TBD The Distance_and_Bearing_Representation class provides a method of encoding the position of a point by measuring its distance and direction (azimuth angle) from another point. The Equirectangular class contains parameters for the Equirectangular projection. TBD The Geodetic_Model class provides parameters describing the shape of the planet. The Geographic class provides information about the quantities of latitude and longitude which define the position of a point on a planetary body's surface with respect to a reference spheroid. The Grid_Coordinate_System class defines a plane-rectangular coordinate system usually based on, and mathematically adjusted to, a map projection so that geographic positions can be readily transformed to and from plane coordinates. The Horizontal_Coordinate_System_Definition class provides the reference frame or system from which linear or angular quantities are measured and assigned to the position that a point occupies. The Lambert_Conformal_Conic class contains parameters for the Lambert Conformal Conic projection. The Local class provides a description of any coordinate system that is not aligned with the surface of the planet. The Local_Planar class defines any right-handed planar coordinate system of which the z-axis coincides with a plumb line through the origin that locally is aligned with the surface of the planet. The Map_Projection class provides the systematic representation of all or part of the surface of a planet on a plane or developable surface. An abstract class that serves as the parent class to all the map projections. The Map_Projection class provides the systematic representation of all or part of the surface of a planet on a plane or developable surface from the perspective of an in-situ spacecraft. The Oblique_Line_Azimuth class defines the method used to describe the line along which an oblique mercator map projection is centered using the map projection origin and an azimuth. The Oblique_Line_Point class defines the method used to describe the line along which an oblique mercator map projection is centered using two points near the limits of the mapped region that define the center line. The Oblique_Line_Point_Group class provides the coordinates in latitude and longitude of one end point of the line along which an oblique mercator map projection is centered. The Oblique_Mercator class contains parameters for the Oblique Mercator projection. TBD TBD TBD The Pixel_Position_Nadir_Polar class specifies the sample coordinate of the location in the image of the "special" point of the mosaic. For Polar projections, this is the nadir of the polar projection. In PDS3, this information was specified using the LINE_PROJECTION_OFFSET and SAMPLE_PROJECTION_OFFSET keywords. The Pixel_Position_Origin class specifies the sample coordinate of the location in the image of the "special" point of the mosaic. For Vertical, Orthographic and Orthorectified projections, this is the origin of the projected coordinate system, corresponding to the Vector_Projection_Origin. In PDS3, this information was specified using the LINE_PROJECTION_OFFSET and SAMPLE_PROJECTION_OFFSET keywords. The Planar class provides the quantities of distances, or distances and angles, which define the position of a point on a reference plane to which the surface of a planet has been projected. The Planar_Coordinate_Information class provides information about the coordinate system developed on the planar surface. TBD The Polar_Stereographic class contains parameters for the Polar Stereographic projection. The Polyconic class contains parameters for the Polyconic projection. The Sinusoidal class contains parameters for the Sinusoidal projection. The Spatial_Domain class describes the geographic areal domain of the data set. The Spatial_Reference_Information class provides a description of the reference frame for, and the means to encode, coordinates in a data set. The State_Plane_Coordinate_System class defines a plane-rectangular coordinate system established for each state in the United States by the National Geodetic Survey. TBD TBD TBD The Transverse_Mercator class contains parameters for the Transverse Mercator projection. The Universal_Polar_Stereographic class defines a grid system based on the polar stereographic projection, applied to the planet's polar regions north of 84 degrees north and south of 80 degrees south. The Universal_Transverse_Mercator class defines a grid system based on the transverse mercator projection, applied between latitudes 84 degrees north and 80 degrees south on the planet's surface. The Vector_Cartesian_Position_Base is a three dimensional, rectangular coordinates vector. Uses units of length. The included attributes are not sufficient to identify the endpoints of the vector. This is a generic unit vector in Cartesian space. The "x", "y", and "z" component have no units and are restricted to values between -1.0 and 1.0 inclusive. Further the length of the vector square root of the (sum of the squares of the components) must be 1.0. The Vector_Length_Base is an abstract class that forms the base of length-based x, y, z vectors. The Vector_Projection_Origin class specifies the location of the origin of the projection. For Polar and Cylindrical projections, this is the XYZ point from which all the azimuth/elevation rays emanate. For the Cylindrical-Perspective projection, this defines the center of the circle around which the synthetic camera orbits. For Orthographic, Orthorectified, and Vertical projections, this optional keyword specifies the point on the projection plane that serves as the origin of the projection (i.e. all points on a line through this point in the direction of PROJECTION_Z_AXIS_VECTOR will be ocated at X=Y=0 in the projection). If not present, (0,0,0) should be assumed. This translation is generally not necessary and not often used; the (X|Y)_AXIS_MINIMUM and (X|Y)_AXIS_MAXIMUM fields allow the mosaic to be located arbitrarily in the projection plane. The Vector_Projection_X_Axis class specifies a unit vector defining the X-axis for a given projection. For Orthographic, Orthorectified, and Vertical projections, this vector defines how the * axis in the mosaic is oriented in space. The X and Y axis vectors together define the rotation of the projection plane around the projection axis. The Vector_Projection_Y_Axis class specifies a unit vector defining the Y-axis for a given projection. For Orthographic, Orthorectified, and Vertical projections, this vector defines how the * axis in the mosaic is oriented in space. The X and Y axis vectors together define the rotation of the projection plane around the projection axis. The Vector_Projection_Z_Axis class specifies a unit vector defining the Z axis for a given projection. For Orthographic, Orthorectified, and Vertical projections, this vector defines the projection axis for the mosaic. All points along a line parallel to this axis are projected to the same spot in the projection plane. For the Cylindrical-Perspective projections, this defines the new axis of the circle around which the synthetic camera orbits (i.e. the normal to the circle), after the cameras have been rotated to correct for rover tilt. CAMERA_ROTATION_AXIS_VECTOR contains the axis before rotation; the difference in these two indicate the rotation amount. The Vector_Sphere_Center class specifies the center of the sphere. This point is measured in the coordinates specified by the Coordinate_Space reference in the Map_Projection_Lander class. The Vector_Surface_Ground_Location class specifies any point on the surface. This point is measured in the coordinates specified by the Coordinate_Space reference in the Map_Projection_Lander class. The Vector_Surface_Normal class specifies a vector normal to the planar surface. This vector is measured in the coordinates specified by the Coordinate_Space reference in the Map_Projection_Lander class. TBD This section contains the simpleTypes that provide more constraints than those at the base data type level. The simpleTypes defined here build on the base data types. This is another component of the common dictionary and therefore falls within the pds namespace. The azimuth_measure_point_longitude attribute provides the longitude of the map projection origin. The azimuthal_angle attribute provides the angle measured clockwise from north, and expressed in degrees. The bearing_reference_direction attribute specifies the direction from which the bearing is measured. The bearing_reference_meridian attribute specifies the axis from which the bearing is measured. The bearing_resolution attribute provides the minimum angle measurable between two points. The distance_resolution attribute provides the minimum distance measurable between two points, expressed in Planar Distance Units of measure. The east_bounding_coordinate attribute provides the eastern-most coordinate of the limit of coverage expressed in longitude. The grid_coordinate_system_name attribute provides the name of the grid coordinate system. The map_projection_name attribute provides the name of the map projection. The latitude_of_projection_origin attribute defines the latitude chosen as the origin of rectangular coordinates for a map projection. The latitude_resolution attribute indicates the minimum difference between two adjacent latitude values expressed in angular units of measure. The latitude_type attribute defines the type of latitude (planetographic, planetocentric) used within a cartographic product and as reflected in attribute values within associated PDS labels. The IAU definition for direction of positive longitude should be adopted: http://astrogeology.usgs.gov/groups/IAU-WGCCRE. The line attribute specifies the line number in the image. The local_description attribute provides a description of the coordinate system and its orientation to the surface of a planet. The local_georeference_information attribute provides a description of the information provided to register the local system to a planet (e.g. control points, satellite ephemeral data, inertial navigation data). The local_planar_description attribute provides a description of the local planar system. The local_planar_georeference_information attribute provides a description of the information provided to register the local planar system to a planet (e.g. control points, satellite ephemeral data, inertial navigation data). The longitude_direction attribute identifies the direction of longitude (e.g. POSITIVE_EAST or POSITIVE_WEST) for a planet. The IAU definition for direction of positive longitude is adopted. Typically, for planets with prograde rotations, positive longitude direction is to the west. For planets with retrograde rotations, positive longitude direction is to the east. Note: The longitude_direction attribute should be used for planetographc systems, but not for planetocentric. The longitude_of_central_meridian attribute defines the line of longitude at the center of a map projection generally used as the basis for constructing the projection. The longitude_resolution attribute indicates the minimum difference between two adjacent longitude values expressed in angular units of measure. The map_projection_name attribute provides the name of the map projection. The maximum_elevation attribute specifies the elevation (as defined by the coordinate system) of the first line of the image. For the Polar projection, specifies the highest elevation used, i.e. the elevation of the outermost circle of pixels. Applies to lander map projections Cylindrical, Polar, Sinusoidal, Perspective and Cylindrical-Perspective. The minimum_elevation attribute specifies the elevation (as defined by the coordinate system) of the last line of the image for Cylindrical map projections. Applies to Cylindrical, Perspective and Cylindrical-Perspective lander map projections. The north_bounding_coordinate attribute provides the northern-most coordinate of the limit of coverage expressed in latitude. The oblique_line_latitude attribute provides the latitude of a point defining the oblique line. The oblique_line_longitude attribute provides the longitude of a point defining the oblique line. The pixel_resolution_x and pixel_resolution_y attributes indicate the image array pixel resolution (distance/pixel or degree/pixel) relative to the Cartesian (x,y) coordinate system as defined by the map projection. Due to varying properties across different map projections, actual surface distances for an individual pixel may be accurate only at specific location(s) within the image array (e.g. reference latitude or longitude, standard parallels, etc). For most PDS products, x and y resolution values are equal ('square' pixels). The inclusion of both x and y attributes allows for anticipated products where resolution may differ for each axis ('rectangular' pixels). NOTE: Definition of this PDS4 attribute differs from how 'resolution' was defined within PDS3. The pixel_resolution_x and pixel_resolution_y attributes indicate the image array pixel resolution (distance/pixel or degree/pixel) relative to the Cartesian (x,y) coordinate system as defined by the map projection. Due to varying properties across different map projections, actual surface distances for an individual pixel may be accurate only at specific location(s) within the image array (e.g. reference latitude or longitude, standard parallels, etc). For most PDS products, x and y resolution values are equal ('square' pixels). The inclusion of both x and y attributes allows for anticipated products where resolution may differ for each axis ('rectangular' pixels). NOTE: Definition of this PDS4 attribute differs from how 'resolution' was defined within PDS3. The pixel_scale attribute indicate the image array pixel scale (pixel/degree or pixel/distance) relative to the referenced coordinate system as defined by the map projection. This attribute should be used in lieu of pixel_scale_x and pixel_scale_y when the pixel scale is not x/y aligned. i.e. a radial pixel scale. NOTE: Definition of this PDS4 attribute differs from how 'scale' was defined within PDS3 The pixel_scale_x and pixel_scale_y attributes indicate the image array pixel scale (pixel/degree or pixel/distance) relative to the Cartesian (x,y) coordinate system as defined by the map projection. Due to varying properties across different map projections, actual surface distances for an individual pixel may be accurate only at specific location(s) within the image array (e.g. reference latitude or longitude, standard parallels, etc). For most PDS products, x and y scale values are equal ('square' pixels). The inclusion of both x and y attributes allows for anticipated products where scale may differ for each axis ('rectangular' pixels). NOTE1: For presentation of hard-copy maps, a map scale is traditionally expressed as a 'representative fraction' (the ratio of a hard-copy map to the actual subject surface (e.g. 1:250,000, where one unit of measure on the map equals 250,000 of the same unit on the body surface)). This usage is relevant when map/data are presented on hard-copy media (paper, computer screen,etc). When defining pixel scale within a stored image/array context here, we are expressing a ratio between the image array and the actual surface (thus, pixel/degree or pixel/distance units). NOTE2: Definition of this PDS4 attribute differs from how 'scale' was defined within PDS3 The pixel_scale_x and pixel_scale_y attributes indicate the image array pixel scale (pixel/degree or pixel/distance) relative to the Cartesian (x,y) coordinate system as defined by the map projection. Due to varying properties across different map projections, actual surface distances for an individual pixel may be accurate only at specific location(s) within the image array (e.g. reference latitude or longitude, standard parallels, etc). For most PDS products, x and y scale values are equal ('square' pixels). The inclusion of both x and y attributes allows for anticipated products where scale may differ for each axis ('rectangular' pixels). NOTE1: For presentation of hard-copy maps, a map scale is traditionally expressed as a 'representative fraction' (the ratio of a hard-copy map to the actual subject surface (e.g. 1:250,000, where one unit of measure on the map equals 250,000 of the same unit on the body surface)). This usage is relevant when map/data are presented on hard-copy media (paper, computer screen,etc). When defining pixel scale within a stored image/array context here, we are expressing a ratio between the image array and the actual surface (thus, pixel/degree or pixel/distance units). NOTE2: Definition of this PDS4 attribute differs from how 'scale' was defined within PDS3 The planar_coordinate_encoding_method attribute indicates the means used to represent horizontal positions. The polar_radius attribute provides the value of the semiminor axis of the ellipsoid that defines the approximate shape of a target body. The polar radius is normal to the plane defined by the semi-major and semi-minor axes. The projection_axis_offset attribute specifies an offset from a projection axis in a map projection. For the Cylindrical-Perspective projection, this is the radius of a circle which represents the rotation around the projection origin of the synthetic camera used to calculate each column. The projection_azimuth attribute specifies the azimuth of the horizontal center of projection for the Perspective lander map projection (loosely, where the camera model is pointing). The projection_elevation attribute specifies the elevation of the vertical center of projection (loosely, where the camera is pointing). For Perspective lander map projection, this applies to the single output camera model; for Cylindrical-Perspective it applies to each columns output camera model, before the rotation specified by Vector_Projection_Z_Axis. The projection_elevation_line attribute specifies the image line which corresponds to the projection_elevation attribute for each column of the Cylindrical-Perspective projection, before the rotation specified by Vector_Projection_Z_Axis. The reference_azimuth attribute specifies the azimuth of the line extending from the center of the image to the top center of the image with respect to a polar projection.. The sample attribute specifies the sample number The scale_factor_at_center_line attribute provides a multiplier for reducing a distance obtained from a map by computation or scaling to the actual distance along the center line. The scale_factor_at_central_meridian attribute provides a multiplier for reducing a distance obtained from a map by computation or scaling to the actual distance along the central meridian. The scale_factor_at_projection_origin attribute provides a multiplier for reducing a distance obtained from a map by computation or scaling to the actual distance at the projection origin. The semi_major_axis attribute provides the radius of the equatorial axis of the ellipsoid. The semi_minor_radius attribute provides the value of the intermediate axis of the ellipsoid that defines the approximate shape of a target body. The semi-minor axis is usually in the equatorial plane. The south_bounding_coordinate attribute provides the southern-most coordinate of the limit of coverage expressed in latitude. The spcs_zone_identifier attribute identifies the SPCS zone. The sphere_intersection_count attribute specifies the number of the intersection to use for the spherical surface model when the camera is outside the sphere. For example, specifying a value of 1 would indicate the first intersection with the sphere should be used (more useful for modeling hills or rocks), while a value of 2 would indicate the second intersection with the sphere should be used (more useful for modeling craters). In PDS3, this was overloaded as part of the SURFACE_MODEL_TYPE keyword. The sphere_radius attribute specifies the radius of the spherical body. In PDS3, this was specified using the SURFACE_NORMAL_VECTOR keyword. The spheroid_name attribute provides the identification given to established representations of a planet's shape. The standard_parallel_1 attribute defines the first standard parallel (applicable only for specific projections), the first line of constant latitude at which the surface of the planet and the plane or developable surface intersect. The standard_parallel_2 attribute defines the second standard parallel (applicable only for specific projections, a subset of specific projections where a first standard parallel is applicable), the second line of constant latitude at which the surface of the planet and the plane or developable surface intersect. The start_azimuth specifies the angular distance from a fixed reference position at which an image or observation starts. Azimuth is measured in a spherical coordinate system, in a plane normal to the principal axis. Azimuth values increase according to the right hand rule relative to the positive direction of the principal axis of the spherical coordinate system. For lander map projections, this attribute specifies the azimuth of the left edge of the output map. Applies to Cylindrical and Cylindrical-Perspective lander map projections only. The stop_azimuth attribute pecifies the angular distance from a fixed reference position at which an image or observation stops. Azimuth is measured in a spherical coordinate system, in a plane normal to the principal axis. Azimuth values increase according to the right hand rule relative to the positive direction of the principal axis of the spherical coordinate system. For lander map projections, this attribute specifies the azimuth of the right edge of the output map. Applies to Cylindrical and Cylindrical-Perspective lander map projections only. The straight_vertical_longitude_from_pole attribute provides the longitude oriented straight up from the North or South Pole. Specifies the type of surface used for the reprojection performed during the mosaicking process. Valid values: Planar - refers to a flat planar model; Spherical refers to a spherical model where the camera is at the center of the sphere. The upperleft_corner_x and upperleft_corner_y attributes provide the projection x and y values, in meters, relative to the map projection origin, at sample 0.5 and line 0.5 (upper left corner of pixel 1,1 within image array). The upperleft_corner_x and upperleft_corner_y attributes provide the projection x and y values, in meters, relative to the map projection origin, at sample 0.5 and line 0.5 (upper left corner of pixel 1,1 within image array). The ups_zone_identifier attribute provides an identifier for the UPS zone. The utm_zone_number attribute provides the identifier for the UTM zone. The west_bounding_coordinate attribute provides the western-most coordinate of the limit of coverage expressed in longitude. The x_axis_maximum attribute specifies the value of the X coordinate (measured in the projection frame) of a Vertical, Orthographic or Orthorectified lander map projection at the top of the image. Note that +X is at the top of the image and +Y is at the right, so +X corresponds to North in the Vertical projection. The x_axis_minimum attribute specifies the value of the X coordinate (measured in the projection frame) of a Vertical, Orthographic or Orthorectified lander map projection at the bottom of the image. The x_length attribute represents length in the x-direction. The x component of a Cartesian position vector. The x component of a unit vector. The y_axis_minimum attribute specifies the value of the Y coordinate (measured in the projection frame) of a Vertical, Orthographic or Orthorectified lander map projection at the right edge of the image. The y_axis_minimum attribute specifies the value of the Y coordinate (measured in the projection frame) of a Vertical, Orthographic or Orthorectified lander map projection at the left edge of the image. The y_length attribute represents length in the y-direction. The y component of a Cartesian position vector. The y component of a unit vector. The z_length attribute represents length in the z-direction. The z component of a Cartesian position vector. The z component of a unit vector. The zero_elevation_line attribute specifies the image line representing 0.0 degree elevation. Applies to Cylindrical lander map projections. [ { "dataDictionary": { "Title": "PDS4 Data Dictionary" , "Version": "1.9.0.0" , "Date": "Fri Mar 30 15:51:19 PDT 2018" , "Description": "This document is a dump of the contents of the PDS4 Data Dictionary" , "PropertyMapDictionary": [ ] } } ]