Viking VISAB Digital Terrain Models (DTM)

DTM – Digital Terrain Models

Instrument: Visual Imaging Subsystem Cameras A and B

PDS Data Set ID: VO1/VO2-M-VIS-5-DTM-V1.0DOI: 10.17189/1520376

For more information about VISAB DTM products, see the Data Set Catalog File.

The Visual Imaging Subsystem Cameras A and B (VISAB) Digital Terrain Models (DTMs) are rasters of topographic data created by special geodetic and photogrammetric processing. The format is similar to that of the Digital Image Models (MDIMs), except that elevation values are used in the array instead of image brightness values. DTMs have resolutions of 1/64 deg/pixel (943m), 1/16 deg/pixel (3.69km), and 1/4 deg/pixel.

Note: The west positive aerographic coordinates in the label of Viking Orbiter VISAB DTM data products have been converted to east positive aerocentric coordinates in the ODE metadata database.

VISAB DTM products have the following file names:

Twaadooo.IMG

where:

w = resolution code for image file (in degree/pixel)

C = 1/4

E = 1/16

G = 1/64

aa = central latitude value rounded down to nearest whole latitude

d = latitude direction

N = North latitude

S = South latitude

ooo = central longitude value rounded down to nearest whole longitude

In ODE, DTM products have the following Product IDs:

TWAADOOO.IMG