avlcpt - Man Page

convert ArcView™ Legend gradients to GMT colour palette tables


avlcpt [-b rgb] [-f rgb] [-h] [-l adjust] [-n rgb] [-o file] [-p precision] [-u adjust] [-v] [-V] [file]


The avlcpt utility will extract a gradient from an ArcView Legend (avl) file and write it to the GMT (Generic Mapping Tools) cpt format. Note that not every avl file will contain a gradient, some just have patterns.

The program will read from stdin if a file is not specified as the final argument, and write to stdout if the -o option is not specified.


In the following, all rgb specifications should be of the form red/green/blue where the colour components are integers in the range 0 to 255.

-b,  --background rgb

Set the background colour of the output.

--backtrace-file path

Specify a file to which to write a formatted backtrace. The file will only be created if there is a backtrace created, typically when an error occurs.

--backtrace-format format

Specify the format of the backtrace written to the files specified by --backtrace-file, one of plain, xml or json.

-f,  --foreground rgb

Set the foreground colour of the output.

-h,  --help

Brief help.

-l,  --lower adjust

Decrease the lower limit on each segment by the specified amount.

-n,  --nan rgb

Set the NaN (no data) colour of the output.

-o,  --output file

Write the output to file, rather than stdout.

-p,  --precision precision

Specify rounding. ArcView legends have a rather interesting approach to height specification whereby colour ranges might be 0-49, 50-99, and so on. The cpt format requires that the end of one segment be at the same as the start of the next, so some rounding of the input will usually be required. The precision is specified directly rather than by number of digits, so that -p10 will round to the nearest 10 and so on.

-u,  --upper adjust

Increase the upper limit on each segment by the specified amount.

-v,  --verbose

Verbose operation.

-V,  --version

Version information.


ArcView™ is a trademark of Environmental Systems Research Institute, Inc.


J. J. Green

See Also



9 September 2020 CPTUTILS User commands