DDB2JPEG

Program Description:

Allows the user to convert a Jumpstart Collection Dynamic DataBase (DDB) complex stripmap image to 8-bit JFIF (JPEG) format.

Program Usage:

js_ddb2jpeg -i <infile> -o <outfile> -e -h -q [qf] -t [0-7]

Switches:

• -e = Auto-contrast enhance output (Def: none)
• -h = Dump Phoenix (ASCII) header (Def: none)
• -q [qf] = Compression quality factor (5-95, Def:75)
• -t [0-7] = Convert specific tile of data (ONLY for images whose height >= 1024)

Description of Arguments:

• <infile> : Input (complex) Jumpstart DDB stripmap image filename
• <outfile> : Output JPEG image filename
• -e : Optional auto-enhancement switch
• -h : Optional Phoenix header dump switch
• -q [qf] : Optional compression factor switch
• -t [0-7] : Optional single tile conversion switch

Files Necessary to Compile:

• Include : jpeglib.h (Contains JPEG file defs.)
• Library : JPEG libjpeg library (OS-dependent)
• Source : js_ddb2jpeg.c read_switch.c
• Make : js_ddb2jpeg.mk (optional)

Compiling and Linking Code:

• You can compile js_ddb2jpeg either from the command line or by using the included makefile (note: .mk file).
• a) Command line Method:
  • % gcc -c read_switch.c
  • % gcc -o js_ddb2jpeg js_ddb2jpeg.c read_switch.o libjpegSunOS.a -l

NOTE: You can use other C compilers. Edit .mk file as necessary. You also may need to re-make JPEG library if using non-Sun machine. You can download the JPEG library source code by clicking here.

• b) Using the Makefile [js_ddb2jpeg.mk]:

Perform the following steps:

1. % make -f js_ddb2jpeg.mk
   (Creates executable: js_ddb2jpeg)
2. % make -f js_ddb2jpeg.mk clean
   (Deletes object code )