1988 LAS Land Analysis System

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Detailed Description

A 1988 video from the USGS Earth Resources Observation and Science (EROS) Center on the Land Analysis System


Date Taken:

Length: 00:14:30

Location Taken: Sioux Falls, SD, US


The Land Analysis System, or LAS, is an integrated digital analysis system designed to support remote sensing, image processing, and geographic information systems applications and research. The development of LAS was a cooperative effort between the National Aeronautics and Space Administration’s Goddard Space Flight Center and the U.S. Geological Survey’s Earth Resources Observation Systems – EROS – Data Center. The idea for a system developed in the early 1980s when the Goddard Space Flight Center identified the need for image processing software to investigate the radiometric andgeometric characteristics of the new thematic mapper scanner on board Landsat D, later designated Landsat 4. This system became known as the Landsat Assessment System. In 1982, the Goddard Space Flight Center decided to expand the scope of LAS to provide more functional capabilities for processing a broader range of image data. A year later, the system was renamed the Land Analysis System to reflect this change. Initially released to users in August of 1985, the system is configured under a transportable executive that provides a standard interface to all applications and a friendly, flexible environment for new and experienced users. Because of LAS’s transportability objectives, government agencies, universities, and other users will receive a wide variety of functions and statistical tools for their unique analysis needs on a variety of computer systems. LAS is composed of six basic components that offer a wide spectrum of functions and statistical tools designed to ingest, manipulate, and analyze digital data. Together, these six components provide the user with the necessary tools to perform image processing and analysis effectively and efficiently. Running under the transportable applications executive, or TAE, interface, LAS provides a flexible framework for algorithm development, application projects, and production image processing. As a user interface management system, TAE provides a standard interface to all applications with a friendly and flexible environment for both new and experienced users. It shields the user from the host computer system but allows the user to enter the operating system whenever desired. TAE also provides menus for program selection, tutored displays for setting program parameters, a command mode for program selection by experienced users, extensive online help features for beginners, and the capability to process in either batch or interactive modes. As a subsystem, TAE manages its own catalog of images and associated files. This catalog manager creates, catalogs, accesses, archives, and retrieves files. While TAE represents the backbone of LAS, a set of 280 data processing, analysis, and display modules form the system’s core. These application modules provide the user with the necessary tools to perform various analyses of image data. They can be categorized into the general functional areas of data input and output, pre-processing, signal processing, image classification, spatial manipulation, data display, custom product generation, tabular data processing, and statistical analysis. Another component is the LAS display subsystem. It’s comprised of an underlying structure called the display management subsystem, to which the application’s modules have been interfaced. The application’s display modules allow users to display, manipulate, and store both image and graphical data. An additional capability in LAS, specifically requested by users, is an interface to a database management system. It permits users to ingest, store, organize, retrieve, and manipulate a variety of data types within the LAS framework. Another important part of any analysis system is a statistical package. Available packages range from libraries of routines that programs may call to highly interactive packages that allow users to input data, perform calculations, and create output graphics. A statistical package can be used in LAS to createa sampling strategy for cluster analysis or to perform regression analysis on portions of multitemporal Landsat scenes. The capability for data transfers between raster and vector data structure systems has become a necessary LAS component to fulfill the mission of the EROS Data Center. Data transfers of raster images and associated information between software packages on the same computer and between computers on the center’s network are executed under the raster data interface, or RDI. Although LAS is primarily a raster-based processing system, vector data is becoming increasingly important in research, development, and project work at EROS. Consequently, it’s essential to have a vector data interface, or VDI, to transfer data between LAS and the software systems at EROS that store their data in a vector format. As a result, LAS offers many functional advantages and useful features to new and experienced users through its basic components. Because the staff at the EROS Data Center comprises a diverse user community with research, applications, and production responsibilities, LAS development at the center continues to provide additional capabilities. These interests range from remote sensing research and development through image processing and custom product generation to involvement in geographic information systems, or GIS, cooperative projects. Because of all the advantages that LAS offers, the list of government agencies, universities, and other users interested in using the system continues to expand. For example, one of LAS’s many applications is in land cover classification. EROS scientists used LAS to develop an effective procedure to transfer complex raster-based land cover data of Alaska to a vector-based geographic information system. By using selected LAS functions, EROS application scientists found that they could reduce the amount of land cover data without jeopardizing its integrity, reduce the time required for analysis, and simplify the resulting land cover map. LAS also has been used to provide irrigated crop inventories. EROS scientists, in cooperation with the U.S. Geological Survey’s Water Resources Division, used LAS to help determine acreages of groundwater- irrigated crops for the Columbia Plateau region of the state of Washington. The results of unsupervised clustering and maximum likelihood spectral classification procedures were taken from LAS and incorporated into a groundwater use regression model for the plateau. The Land Analysis System can be used as a flexible tool for navigation purposes as well. Traditionally, the National Oceanic and Atmospheric Administration’s National Ocean Service, or NOS, manually depicted shaded relief for aeronautical charts by using air brush and pencil techniques. Because those drafting skills no longer exist at NOS, the agency turned to the EROS Data Center and LAS when it was mandated to extend the area coverage for the Los Angeles terminal air chart. Through LAS, EROS developed an automated technique to generate the map separate from digital elevation models for the hill-shading portion of NOS’s air charts. The result is a rendition of the terrain on the chart that’s repeatable and unbiased, accomplished in less than 20% of the time and at one-fourth the cost of the traditional manual method. LAS has also proved successful in monitoring insect infestations in western Africa. The U.S. Agency for International Development implemented LAS to develop procedures and standards for using local area coverage data from the advanced very high-resolution radiometer sensor aboard the National Oceanic and Atmospheric Administration’s polar-orbiting satellites. A method was devised to prepare composites of time series vegetation conditions. The procedures taken from LAS are now being used to map and monitor grasshopper and locust habitat conditions in countries such as Senegal and Gambia. In addition to the Water Resources Division irrigated crop inventory, the Federal Land Information System, the National Ocean Service, and the Agency for International Development Projects, all of the EROS Data Center’s image mapping production is implemented by LAS. Image map production is an experimental USGS National Mapping Division program that produces map products at various scales from Landsatmultispectral scanner, or MSS; thematic mapper, or TM; SPOT, the French satellite mapping system; AVHRR data; and aerial photography covering a wide range of environments. Remotely sensed data are ingested, geometrically registered, mosaiced if needed, and enhanced with the LAS modules into areas that are based on USGS 1-to-250,000,1-to-100,000, or 1-to-24,000 topographic quadrangles. These data are merged with annotation and collar information into an image map that’s published by the Geological Survey’s National Mapping Division. According to the chief of the EROS Data Center, Alan Watkins, as more people use LAS in their  specialized image analysis work,and more applications for the system are developed, the data center will satisfy its obligation to expand the system. - The data center is fully committed to the use, support, and enhancement of the LAS system. This cooperative development activity between the Geological Survey and NASA has given us a powerful public domain image processing and analysis software package with a high degree of transportability. It’s finding increasing use within Interior and many other federal agencies, universities, and private organizations. - LAS originally was developed and released to users on VAX computer systems under the VMS operating system. The EROS Data Center and the Goddard Space Flight Center are working to enhance the transportability of LAS to other computer hardware and operating systems. This is being accomplished through the development of highly transportable application software and support libraries, the use of device-independent interfaces wherever possible, and the implementation of the new transportable LAS on local networks of mini- and micro-computers under the VMS and Unix operating system. The EROS Data Center has installed LAS at its Alaska field office and at the Western Mapping Center, both within the Survey’s National Mapping Division. Several other sites within the Department of the Interior also have expressed interest in obtaining the system. If you want to obtain LAS, or if you need more information on the system, write or call the chief of the computer services branch at the EROS Data Center or the LAS support office at the Goddard Space Flight Center.