NAME

rlesetbg - Set the background value in the RLE header.

SYNOPSIS

rlesetbg [ -{DO} ] [ -c bgcolor ... ] [ -o outfile ] [ infile ]

DESCRIPTION

rlesetbg sets the background color field in the image header of an RLE(5) image (none of the actual pixels are changed). If infile isn't specified, the image is read from stdin.

The background color in the header is used to save space in the run-length encoded file. Runs of background-colored pixels longer than 2 pixels are simply not saved. (Doing this for runs of 1 or 2 background pixels can make the saved image larger than if no encoding were done.) Therefore, changing the background color with rlesetbg may still leave some pixels saved in the original background color. The -D option will delete the background color altogether from the header; this can be useful in certain circumstances, but can also lead to very strange results.

OPTIONS

-D: Delete any background specification that might be present.
-O: Specifies that the image has no background, it overlays existing images.
-c bgcolor ...: Specifies the color values to set the background to. There should be at least as many values as there are color channels in the image. Use -- or another option to separate the list of colors from infile.
-o outfile: If specified, the output will be written to this file. If outfile is "-", or if it is not specified, the output will be written to the standard output stream.

AUTHORS

John W. Peterson and Rod Bogart

BUGS