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DMS Softcopy Version 5.1 is a full featured softcopy photogrammetric software package for use on personal computers running the Windows XP operating system. DMS Softcopy is designed to facilitate mapping from stereo and monoscopic image data in digital format, including scanned aerial photographs and satellite images.
A full complement of image processing routines perform enhancement and data
management functions. Rigorous photogrammetric solutions are employed to extract
accurate coordinate information from scanned aerial photographs for use in
automated generation of digital elevation models (DEMs), relief corrected
planimetry, contours and digital orthophotos. Functions facilitate point
measurement and transfer for aerotriangulation and image-to-image registration
tasks. Planimetric mapping capabilities provide functions for vector map
compilation and revision using rectified and non-rectified images as a raster
backdrop.
DMS Software Specifications
Softcopy Photogrammetry
The DMS Softcopy 5.1 provides a rigorous yet inexpensive softcopy photogrammetric solution for use with scanned aerial photographs. Stereomodels are viewed in anaglyph 3D on a standard computer display for topographic mapping, map compilation and map revision. The stereomodels may also be employed for DEM generation using automated stereocorrelation techniques. With the DEM generated by stereocorrelation or obtained from agencies such as the U.S. Geological Survey (USGS), air photos and satellite images can be quickly converted to orthoimages.
Image Display and Enhancement
Image, GIS, DEM or vector files may be displayed. Raster images can be zoomed and X, Y, and Z map coordinates, pixel and line coordinates and digital number values recovered by moving the cursor throughout the image. Image enhancements maximize image contrast and improve interpretability for mapping applications. A histogram equalization algorithm is applied to the image pixels and increases the contrast in the image by expanding the range of digital numbers (DN). The l-H-S Transformation permits pan-sharpening with the integration of two or more multispectral/ multiresolution /multitemporal data sets. A typical application of the IHS Transformation is to create a high resolution color image by integrating Quickbird or Ikonos panchromatics and multspectral images, or SPOT Panchromatic data with SPOT XS or Landsat Thematic Mapper multispectral image data. Filters are used to sharpen detail in an image or smooth a DEM.
Geocoding and Image Registration
Raster data files may be geocoded to create new geometrically correct (rectified) data files referenced to a standard coordinate system. The development of registered image data sets for use in GIS applications is automated and readily accomplished.
Points, lines and/or closed polygons traced with a digitizing tablet from maps, aerial photographs, or other hardcopy can be rectified using control points. The resulting coordinates are assigned feature codes/ attributes and stored in GCP or vector files. Ground control points can also be obtained from digital (scanned) map or rectified image data using on-screen digitizing procedures
Softcopy Photo Interpretation
Geocoded raster images provide an excellent base for compiling or revising planimetric maps. Vector files can be established by tracing point, line and polygon features from an image on the display screen. In addition, existing map files in vector format can be overlaid on an image or GIS file for the purpose of map revision or accuracy checking.
Interactive Stereo Mapping
Spot heights, contours and planimetry can be compiled from stereo air photo and satellite image data in digital format. After a stereo model is formed, it can be viewed in 3D and a floating mark employed to measure planimetric map coordinates and elevations. Output is a vector data file of X, Y, Z coordinates corresponding to relief corrected planimetry, spot heights and contours.
Digital Elevation Models (DEM's)
DEMs are created using automated stereocorrelation techniques with a user-specified grid spacing for a stereo image data set. The DEM can then be rectified, used to generate an orthophoto or overlaid with the original image data for terrain visualization. DEMs generated with stereocorrelation from stereo satellite images may be edited. The stereo image is viewed in 3D and the DEM overlaid on top of the image as a grid of floating dots. Erroneous points in the DEM will be apparent because they will appear to either be above or below the ground surface. Using the mouse, posts can be corrected and saved.
Orthoimage Production
Relief displacements may be removed from single satellite or scanned air photo image data sets to create orthoimages. A DEM must be provided either through the use of stereocorrelation techniques, photogrammetry or obtained from another source. The output image will have all of the effects of relief displacement removed.
Digital Image Mosaics
The DMS permits rectified scanned aerial photographs, orthoimages, satellite images and DEM files to be mosaicked together to create a larger file. Multiple vector files also can be merged to form a single file.
Aerotriangulation
Point measurement and transfer functions are provided to facilitate GCP and pass point identification for use in aerotriangulation. DMS provides direct support for the AeroSys aerotriangulation package operational under Windows.
Import/Export DEM Data
DMS will convert an ASCII 1:24,000 scale USGS DEM, as well as other ASCII formats, to DMS format. DMS DEM files can be exported to ArcView ASCII Import format, XYZ point files and USGS DEM.