RE: Transparent GIFs

bede@scotty.mitre.org
Thu, 2 Feb 1995 04:32:40 +0100


Date: Thu, 2 Feb 1995 01:28:52 +0100
From: Steve Cameron <stevecam@interactive.net>

While we're in the GIF neighborhood, is anyone aware of a method to create
transparent GIF files to be used with a browser to give a layered
effect??

The short answer is to use netpbm (formerly called pbmplus), which I
think you can get from ftp.x.org. Here's a very simple little script
which takes a GIF image and makes the color white transparent in the
output (with the file arg renamed with "T_" as a prefix).

- Bede McCall <bede@mitre.org>

The MITRE Corporation Tel: (617) 271-2839
Bedford, Massachusetts FAX: (617) 271-2423

#!/bin/csh
#
# Make a "tranparent-background" GIF image.
#
/bin/cat $1 | /usr/local/pbmplus/bin/giftoppm | /usr/local/pbmplus/bin/ppmtogif -transparent white > T_$1