Wednesday, June 16, 2010

The first ERDAS Manual

Brad Skelton, as a hobby over the years, has been the ERDAS archivist. I enjoy visiting his office and looking at the more than 30 years of ERDAS historical ‘stuff.’ One bit of ‘stuff’ Brad has archived carries a lot of significance, the very first ERDAS Manual. I am embarking on an effort to scan and OCR the document into a searchable PDF that looks exactly like the original document. Two beautiful and multi-talented ERDAS ladies, Candy Billips and Jenn Gazdziak, will help me with the effort. (Truth be told, I could not do it without their help.)

The first ERDAS Manual was written by Mark Finlay, Larry Brantley and Brad Skelton. Andrea Gernazian (Bruce Rado's, one of the three ERDAS founders, wife) proof-read the manual and performed word processing duties along with Melissa Ergle using Wordstar on a Cromemco Z80 microcomputer. The entire document was printed with great effort on a Brother daisy wheel printer (which had the tendency to jam every few pages, or smear printer dust over the pages). Andrea coined the phrase “The Oh, Brother! Printer”.

I quoted from another page of the first ERDAS Manual in the blog post,
A Brief History of ERDAS IMAGINE

Below is the introduction page (page 2-1) from the first manual. Note the spelling error ’digitial,’ which everyone missed in 1983.

INTRODUCTION Rev 7.1 / 1 June 1983
A. ERDAS 2300/2400 SYSTEM

I. Introduction
The ERDAS 2300/2400 system is a complete turn key stand alone image processing system for performing image analysis of remotely sensed data, such as LANDSAT or SPOT satellite data, video digitized image data such as aerial photographs, or gridded polygon data such as digitized soils or topography maps. The ERDAS software package that comes with the 2400 system provides many standard image processing functions , a complete and integrated geographic information system (GIS), polygon capture software for use with a table digitizer, and many data base management utilities, all run in a menu-driven and highly interactive environment. The ERDAS 2400 system may be configured to work with several different image processors, ranging from the low cost Digital Graphics CAT system to the more powerful, higher resolution displays such as the Raster Technologies and Gould (DeAnza) image processors. Through the GIS software, many different types of data may be combined in one analysis to provide solutions to problems that cannot be solved using only one type of data. The ERDAS mapping package can produce true scale hard copy map output on the graphics line printer provided as standard equipment. The amount of data that can be processed and stored on the system is limited only by the amount of disk space that is purchased with the system, and more disk space can always be added later if the need arises. As little as 20 megabytes of storage can be used for small scale image processing requirements, or as much as 1000 megabytes can be purchased. A standard 9-track tape drive is also provided with the system to allow for easy access to digital image data from a large number of sources. A number of different CPUs, ranging from the PDP 11/23+, and MICRO-VAX for small scale operations, up to the VAX 11/780, for large scale image processing, are available to satisfy the most demanding applications. An optional table digitizer may also be purchased to allow the system to capture data directly from maps of almost any scale. Multi-user capability is also provided with the ERDAS system. One or many users may perform data processing simultaneously, and in fact, each individual user can run and manage several concurrently running programs so that tasks such as loading a tape can be performed in the background, while other, more interactive tasks, can be done at the console. Data files may be shared by several users or protected from unauthorized access by the file protection system of the RSXll-M or VMS operating system. The ERDAS system is designed to provide a powerful software tool for managing, displaying, and processing digitial image and geographic data, without requiring sophisticated knowledge of computers or programming.

Copyright 1983, 1984 by ERDAS, Inc. All rights reserved

Thursday, June 3, 2010

Utah State University Image Standardization Tools

Years ago I ran into a tool built by the Remote Sensing/GIS lab and Utah State University. I recently stumbled onto the tool once again and immediately thought of sharing the tool with you folks.

The website states, “This website provides three tools that create ERDAS Imagine TM spatial models (.gmd format). Each tool creates a different .gmd file providing a slightly different approach to standardization. These tools are designed for Landsat 5 TM and Landsat 7 ETM+ scenes and require, as input, the header file (*.h1) accompanying NLAPS formatted imagery from the USGS at Eros Data Center.”

It offers,

  • DN-to-Reflectance Conversion
  • COST Atmospheric Correction
  • COST without Tau (Dark Object Subtraction) Atmospheric Correction

Check it out and have fun...

Utah State University Image Standardization Tools