DOQ Utilities 1.0
Download the programs described on this page. Version 2.0 will contain additional features.

Paper on DOQQs & DRGs
Need more information on DOQQs and DRGs? Download the paper presented at the Southern Forestry Convention (10/98) and GIS/LIS (11/98).

LABINS
A useful website funded by the Florida Department of Environmental Protection containing survey and land information for Florida. Created and maintained by FREAC.

Geographic Information Systems (GISs) have most often employed vector data because its flexibility allows users to easily attach attributes and perform queries and calculations. However, with the introduction of high-quality georeferenced raster images, GIS designers are increasingly incorporating raster layers to visually enhance their systems and provide a Geographic Information Systems with the benefits of vector data combined with the visual impact of raster images.

Digital Orthographic Quarter Quads (DOQQs) are scanned aerial photographs that are rectified to correct for camera lens distortion, tilt and pitch of the airplane and the terrain of the ground. The USGS-supplied images have a ground resolution of one meter. This resolution can be lowered to reflect the needs of the specific system. Digital Raster Graphics (DRGs) are scanned USGS topological sheets. Both DOQQs and DRGs can be used as visual backdrops in GIS systems. DOQQ's and DRG's can be easily combined with other digital cartographic products such as digital elevation models (DEM) and Digital Line Graphs (DLG). The DOQQ and DRG show great potential as tools for validating and assessing other digital data.

In order to be used with existing GIS data, raster images must be compatible with other GIS data. In many cases, the DOQQ's may need to be georeferenced to NAD83 or NAD27, resampled, reprojected, merged into a seamless image, or converted to another graphic format. The DRG's may need to be reprojected, have the "collars" (the white area around the map) removed, and be merged into a seamless image.

FREAC has assembled a collection of DOQQ utility programs to easily perform these tasks using ARC/INFO.


What the Utilities Do

Input

Three-band Digital Ortho Quarter-Quads on CD-ROM distributed by USGS.

(Files on CD are expected to be in the new bip 80-character format using conventional naming. For example, the four quarter-quads should be named similar to: lake_jackson.nws, lake_jackson.nes, lake_jackson.sws, and lake_jackson.ses.)

Georeferenced images in the following formats: TIFF, ERDAS (LAN and IMG), BIL, BIP, JFIF (.JPG), BMP, BSQ, or RLC.

• Projection from UTM to state plane (other projections available with Version 2.0)
• Resampling at user-specified rate
• Merging of four quarter-quads into one image (available with Version 2.0)
• One-band image processing (available with Version 2.0)

• Datum can be NAD 83 or NAD27
• Three user-specified file paths (input, output, and working area) helps task organization
• No advanced knowledge of ARC/INFO is necessary

• Designed for DEC Alpha and RS6000 workstations. (Not tested on the SUN platform.)
• Designed for ARC/INFO 7.0 (Will run at the 6.x level with the exception of conversion to JPG format)
• ARC/INFO GRID license is necessary for reprojection
• At least 1.5 G of disk space is necessary for temporary workspace; 600 megabytes for the output files
• FORTRAN compiler (if using a system other than RS6000 or DEC Alpha)

1.
Determine Where You Will Work
Three folders are needed: doqutil (1 MB) for the .amls; doqout (600 MB) for the final product; doqtemp (1.5 GB) for the temporary files. You will also need a doqsource folder if not reading from CD. (You can have it all in one folder, but it is generally less confusing to separate the working space from the final product.)

2.
Create the “DOQ Utility Folder” (doqutil)
Copy files from the diskette to the doqutil workspace with the tar command. Type: tar -xvf /dev/fd0 (substitute floppy drive name)
Create the “DOQ Output Folder” (doqout)
This folder will hold the output graphic files. At least 600 MB is required. Type /doqout when the program asks for the output path name.
Create the “DOQ Temporary Folder” (doqtemp) This directory should have at least 1.5 gigabytes of available disk space and should be an ARC/INFO “workspace”. (To create the workspace, start ARC and type: create temp; kill temp). Type /doqtemp when the program asks for the work area path name.

3.
Compile the Fortran Program
If running on an RS6000, copy the file named newdoqload_rs6000.exe to newdoqload.exe. If running on a DEC Alpha, copy the file named newdoqload_alpha.exe to newdoqload.exe. Otherwise, compile the fortran program newdoqload.f on your workstation using your fortran compiler. Name the file newdoqload.exe. The executable should reside in the doqutil folder.

4.
Run the Program
From the doqutil folder, start arc; and type &r doqq. Fill out the forms to reflect your choices. If you are processing a quad for the first time, be sure to answer Yes to the cleanup option to erase previous work. Be aware the reprojections will take 4 - 6 hours on “medium” powered machines.

5.
What Happens Next
Input files are read from the CD. Output files are written to the doqout folder. Temporary files and grids remain in the doqtemp folder until a new quad is processed.