San Francisco Bay Area Regional Database (BARD)

Using "OLD Header" DOQs in ARCVIEW and ARC/INFO

If you are working with DOQs containing the new header format go to the New header format page.
In order to use the DOQs in ARC/INFO or ARCVIEW you need to do the following:
If you purchased DOQ data and received an 8 mm tape, do step 1, otherwise skip.

1. Read in the DOQs from tape (unix OS) using dd if=tape-device-name of=output_file bs=blocksize

   NOTE: Use the no-rewind option on the tape device when reading multiple files.

   NOTE: To georeference BARDs compressed(JPEG) DOQs you should uncompress  
         them first using a jpeg uncompression program, or georeference the
         jpeg files (without uncompressing) by create a world file(jgw.)
         Two uncompresion utilities are available from out site. 
           One for the Data General or one for Windows95, windows NT. 
         For source code you can also visit the Independent JPEG Group's via anonymous FTP.

    
2. Rename the doq file to contain a .bil extension.
3. Create a ascii text file using the same name as the .bil but with a .hdr extension
   example: oakland_se.bil and oakland_se.hdr
4. Add lines to the .hdr ascii text file that contains the following information.

nrows        #number of rows or lines in image
ncols        #number of columns or samples in image
ulxmap       #upper left corner x value of pixel 1,1
ulymap       #upper left corner y value of pixel 1,1
skipbytes    #Number of bytes to skip that make up the header 
xdim 1       #dimension of pixel in x direction
ydim 1       #dimension of pixel in y direction
nbands 1     #number of bands in image, nbands 3 for color images

nrows and ncols are "must have" values.  They are contained in
  "SAMPLES_AND_LINES" in the DOQ header (LINES = nrows and SAMPLES = ncols)
   Also will be listed on the paper printout provided with the tape.

ulxmap and ulymap are used to geo-reference the DOQ in UTM coordinates.  
   These values are found at the end of the third header record of each DOQ.
   You can use either NAD 27 or NAD 83 values.

skipbytes is used to avoid display of the header information found at the top
   of each DOQ.  For the old header format the skipbytes is obtained by 
   multiplying the value of ncols times 4. 
   If you are using compressed DOQs the skipbytes value is 8.

xdim and ydim refers to the dimension of the pixels, the default is 1 by 1. 
If you omit the xdim and ydim items you will see no change in your DOQ display.

nbands is 1 if the image is a gray scale image. For a color image nbands is 3 and 
           the extension on the name of the DOQ should be .bip

The information you need for these fields can also be extracted from the header of the individual DOQs.
You can obtain a program that will allow you to read the information from the following links below.

NOTE: The programs available below are for the old DOQ header format.
Programs for the new DOQ header format can be found at the New header format page.

Precompiled PROGRAM to read and display DOQ headers on the Data General using DGUX 5.4.3

Precompiled PROGRAM to read and display DOQ headers on the SUN running solaris 2.4

Precompiled PROGRAM to create a .hdr file for the DATA GENERAL running DGUX 5.4.3

Precompiled PROGRAM to display DOQ header information from a .hdr file for the PC.

You can ftp a menu driven program for Windows(95 or NT) Doq2Arc2.exe .
You will need to ftp 3 other files: 1. tb510.dll , 2. xnmba420.dll , 3. xnmte420.dll

Note: If your browser changes the .dll extension to .exe you must rename them back to .dll

The Files Below are tar files with source code for compiling your own header manipulating routines.

To compile your own version of a program that will read and display DOQ header information.

To compile your own version of a program that will display and create a .hdr file on a windows 95 or NT system.

The above tar files contains various files that you will need in order to create
executable programs if you are using a unix operating system.

Access to our:

Back to BARD Home Page