Image ID Application using GRASS

Guest user guest at crc.com
Wed Feb 3 16:39:56 EST 1993


Being new to the GRASS GIS world, we wanted to see if any other users had
developed an application that is similar to what we wish to develop.  Below
is a short description of our application.  If you wish to respond please
send mail to Jim Fowler (guest at crc.com).  However, if you find it more
convenient to return responses by FAX, our FAX number is 410-312-5600.
(Since we work on a 9600-baud dialup line, FAXs are more convenient for
us.) Otherwise, we'll look for responses daily until 19 Feb 1993 (our
project should be over by then). Thanks.

Jim Fowler  (<--for questions call)
Coleman Research Corp.
9891 Broken Land Pkwy., Suite 200
Columbia, MD 21045
301-621-8600 (voice, Washington, D.C., metro number)
410-720-5155 (voice, Baltimore, Maryland metro number)
410-312-5600 (FAX)
-----
Image Identification (ID) Application

INTRODUCTION:

Imagery (primarily aerial B&W photography at this time) is being collected
on various sites over extended periods of time (>30 years).  The imagery
comes from many sources and has various area coverages, resolutions, etc.
The total number of images currently runs in the hundreds for a typical
site.  Imagery will continue to be collected on these sites over the next
several decades by various sensors (e.g., visible, IR, radar, etc.).

For an operator to identify what imagery is available, a database is being
established.  The database includes fields such as date of image, type of
sensor, sensor resolution, area coverage, and coverage coordinates (center
and corner in lat/long).  Several other parameters and references are
included in the database.  The database is currently in a delimited ASCII
text file.  (A new relational database design is available upon request.)

The utility of this database for imagery identification would be enhanced by
a database retrieval tool which would allow an untrained operator to
identify which images are of interest for his application.  For example,
only imagery which covers a specific period of time, area, sensor, and/or
sensor resolution may be of interest.

PURPOSE:

This application is to provide a means of identifying images of interest.
An operator is to identify these images through four windows:

   - site selection, initial date range (i.e., database search parameters);
   - database entry (textual) selection (i.e., selectable database list);
   - spatial display; and/or,
   - temporal (time-based) display.

Once selection is made, ideally a "user file" would be created which could
be printed or output in some standard format (e.g., for input to word
processing, another database, etc.).  This file would be used by the
operator to retrieve the actual images from within another application.
(The images might be stored in another database, perhaps in one of several
formats, e.g., raw digitized, enhanced, annotated, etc.) An alternative to
the user file would be for the Image ID application to send the results to
the second application or start the second application with the results from
the Image ID application as arguments.

OBJECTIVES:

Develop (or purchase) software application or toolset to provide this
capability.
  
Key features of this application or tool set would include:

   - Setup of search according to site, initial start and ending date, range
     of photo scale values, etc.  This would begin an automatic identifi-
     cation (database search) of images which match these criteria (e.g.,
     all B&W photos which include point x,y (lat, long) during the period
     6/1/50 to 7/5/76).  Then the following two displays would be used to
     further refine the identification (possibly in a repetitive manner).

   - Display of selected image coverage (spatial view).  Image edges (not
     the actual images) would be displayed as rectangular overlays on a map
     background (Figure 1).  When there are multiple overlays, a method
     (i.e., by color and mouse) should be provided to enable identification
     of specific images from the display.  (E.g., selecting an image outline
     will cause the outline to change color AND data will be highlighted for
     the same image in other windows.  The same also applies for deselecting
     an outline.) A zooming and roaming capability should be provided if the
     rectangular overlays have different scales or occupy locations other
     than center of screen.

   - Display of temporal coverage (time-based view).  This display should
     provide a time scale/resolution (selectable, e.g., year, mo, day) and
     date indicators (e.g., dots) for which imagery is available (Figure 2).
     Several "rows" of dates are desired (e.g. sources A, B, and C in Figure
     2); each "row", for example, illustrating one particular sensor or
     source of data.  Another desired feature is providing highlights (e.g.,
     dot color) of those dates which have selected characteristics (e.g.,
     stereo coverage, image scale).  It is desired that the time scale be
     easily adaptable (e.g., zoom mode) to provide the resolution required
     when many images have been acquired over a short period of time.  Also,
     selecting a date indicator in this display would highlight the date
     indicator in this display AND data would be highlighted for the same
     image in other windows.

Requirements for this package:

   - Easily portable to various platforms: the initial delivery (or
     development platform) is to be a Sun with X/Motif windowing, but PCs
     running Unix (or DOS and Windows) may be an alternate delivery platform.

   - Application easily used by non-technical personnel.

   - Application can be compiled and distributed at little or no cost to end
     user.  If run-time packages or other support software is needed, then
     that software needs to be specified along with the associated costs.
     If application can be run remotely with access to run-time packages on
     a network server computer, then this needs to be identified along with
     the associated costs.
------
(These lose something in the graphics-to-text conversion.)

Figure 1.  Spatial Display

   window
   |
   v       map background--------------------+
+----------|---------------------------------|------------------------------+
|          v            +--------------------|----------------------+       |
|  =====================|=======++===========|=========++===========|=====  |
|  road                 |       ||           |         ||           |       |
|             +---------|-----------+        |         ||           |       |
|             |         |   +----------------|------+  ||           |       |
|             |         |   |   ||  | +------|------------------+   |       |
|             |         |   |   ||  | |      |      |  ||       |   |       |
|             |         |   |   ++==|=|======|======|==++       |   |       |
|             |         |   |       | |      v      |           |   |       |
|             |         |   |       | | +=========+ |           |   |       |
|             |         |   |       | | || house || |           |   |       |
|             |         |   |       | | +=========+ |           |   |       |
|             +---------|---|-------+ |             |           |   |       |
|                   ^   |   +---------|-------------+           |   |       |
|                   |   |      ^      +-------------------------+   |       |
|                   |   |      |         ^                          |       |
|                   |   +------|---------|--------------------------+       |
|                   |          |         |                       ^          |
+-------------------|----------|---------|-----------------------|----------+
     series of image outlines--+---------+        image outline--+

Figure 2.  Temporal Display

   window
   |
   v            +--begin             +--end         +--revised end
+---------------|--------------------|--------------|----------------+
|               |                    |              |                |
|   Events  |   v                    v              |                |
|       1  -|   x--------------------X              |                |
|           |                                       v                |
|       2  -|               x------------------X----X                |
|           |                                                        |
|       3  -|                        x-------------------X           |
|           |---------------------------------------------------     |
|   Sources |                                                        |
|       A  -|   o         o            o             o        o      |
|           |                                                        |
|       B  -|      oo o        o o o o o        o     o o o          |
|           |                                           ^            |
|           |    o                         o            |            |
|       C  -|    o   o              o      o       o    |    o       |
|           |    o                         o            |            |
|           +----^------+------------+------------+-----|------+     |
|          1950  |     1960         1970         1980   |     1990   |
|                |                                      |            |
+----------------|--------------------------------------|------------+
                 +--multiple photos, same day         photo available
<end of text>



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