Satellite Enhancement File (.enh)

The satellite enhancement database file is very similar to the color fill database file. The enhancement file is specified with the color_fill resource.

FORMAT

The syntax for each line is:

[value:]color[%Dcolor]
[value:]color[%Dcolor]
...

Where:

• value -- A image value cutoff for the lower end of the color range.
  The color values are image pixel values ranging from 0 to 255.
  The value may be specified as a image pixel value or as a infrared temperature based on the GOES calibration scheme. The temperature is specified by preceding the value by a "c". For example, "c-25" specifies the image pixel value corresponding to -25 Celsius. This way infrared images can be enhanced based on the temperatures the image represents.
• color -- The color name or a range of color values (either numbers or names). The range is specified as follows:
  
  color-color
  
  This represents a contiguous range of numbers or of color names. For example, 2-4 gives colors 2,3,4. The values red-blue will give all the colors between red and blue in the color table.  A color of off can be used to blank out (make transparent) parts of the image.
• Dcolor -- The colors can be specified with dither value D and color. Dither colors are specified by using the following syntax:
  
  %6white
  
  The original or background color is specified followed by a "%", then the dither percent value and the dither or foreground color. The above example uses the 3x3 dither matrix and gives possible dither values of 0 through 9. The result is a 6/9 dither of white over black. Using 0 for the dither value gives the original color. Using 9 for the value gives the only dither color. This is somewhat restrictive for monochrome screens, so a second dither scheme is provided which is a 5x5 dither matrix. This gives a total of 26 possible dither values which are specified by lower case alphabetic characters "a" through "z". The value "a" gives the original color and "z" gives the dither color. For example:
  
  %mwhite
  
  gives a 12/25 dither.
  

The color fill file or more appropriately the enhancement file has an additional line at the beginning of the file that names the enhancement. Here is the MB enhancement file (sat_mb.enh):

MB
0:black
c29:1
2-9
c6:10
11-15
c-31:16
c-32:cyan
c-43:lcyan
c-54:lblue
c-60:blue
c-64:green
c-70:lgreen
c-76:brown
c-81:yellow
c-90:black

SEE ALSO

• xsat

For further information about WXP, email technical-support@weather.unisys.com
Last updated by Dan Vietor on August 10, 1998