XScreenSaver(1) General Commands Manual XScreenSaver(1)
NAME
webcollage - decorate the screen with random images from the web
SYNOPSIS
webcollage [-display host:display.screen] [-root] [-verbose] [-timeout secs] [-delay secs] [-background bg] [-no-output] [-urls-only]
[-size WxH] [-filter command] [-filter2 command] [-http-proxy host[:port]] [-dictionary dictionary-file] [-driftnet [cmd]]
DESCRIPTION
The webcollage program pulls random image off of the World Wide Web and scatters them on the root window. One satisfied customer described
it as "a nonstop pop culture brainbath." This program finds its images by doing random web searches, and extracting images from the
returned pages. It places the images on the root window by using the giftopnm(1), djpeg(1), and xli(1), xv(1), or xloadimage(1) tools.
webcollage is written in perl(1) and requires Perl 5.
It will be an order of magnitude faster if you also have the webcollage-helper program installed (a GDK/JPEG image compositor), but webcol-
lage works without it as well.
webcollage can be used in conjunction with the driftnet(1) program (the Unix equivalent of EtherPEG) to snoop images from traffic on your
local subnet, instead of getting images from search engines.
OPTIONS
webcollage accepts the following options:
-root Draw on the root window. This option is manditory, if output is being produced: drawing to a window other than the root window is
not yet supported.
-verbose or -v
Print diagnostics to stderr. Multiple -v switches increase the amount of output. -v will print out the URLs of the images, and
where they were placed; -vv will print out any warnings, and all URLs being loaded; -vvv will print information on what URLs were
rejected; and so on.
-timeout seconds
How long to wait for a URL to complete before giving up on it and moving on to the next one. Default 30 seconds.
-delay seconds
How long to sleep between images. Default 2 seconds. (Remember that this program probably spends a lot of time waiting for the
network.)
-background color-or-ppm
What to use for the background onto which images are pasted. This may be a color name, a hexadecimal RGB specification in the form
'#rrggbb', or the name of a PPM file.
-size WxH
Normally, the output image will be made to be the size of the screen. This lets you specify the desired size.
-no-output
If this option is specified, then no composite output image will be generated. This is only useful when used in conjunction with
-verbose.
-urls-only
If this option is specified, then no composite output image will be generated: instead, a list of image URLs will be printed on
stdout.
-filter command
Filter all source images through this command. The command must take a PPM file on stdin, and write a new PPM file to stdout. One
good choice for a filter would be:
webcollage -root -filter 'vidwhacker -stdin -stdout'
-filter2 command
Filter the composite image through this command. The -filter option applies to the sub-images; the -filter2 applies to the final,
full-screen image.
-http-proxy host:port
If you must go through a proxy to connect to the web, you can specify it with this option, or with the $http_proxy or $HTTP_PROXY
environment variables.
-dictionary file
Webcollage normally looks at the system's default spell-check dictionary to generate words to feed into the search engines. You
can specify an alternate dictionary with this option.
-driftnet [ args ]
driftnet(1) is a program that snoops your local ethernet for packets that look like they might be image files. It can be used in
conjunction with webcollage to generate a collage of what other people on your network are looking at, instead of a search-engine
collage. If you have driftnet installed on your $PATH, just use the -driftnet option. You can also specify the location of the
program like this:
-driftnet /path/to/driftnet
or, you can provide extra arguments like this:
-driftnet '/path/to/driftnet -extra -args'
Driftnet version 0.1.5 or later is required. Note that the driftnet program requires root access, so you'll have to make driftnet
be setuid-root for this to work. Please exercise caution.
ENVIRONMENT
DISPLAY to get the default host and display number.
XENVIRONMENT
to get the name of a resource file that overrides the global resources stored in the RESOURCE_MANAGER property.
http_proxy or HTTP_PROXY
to get the default HTTP proxy host and port.
FILES AND URLS
/usr/dict/words, /usr/share/lib/dict/words, or /usr/share/dict/words to find the random words to feed to search engines.
http://image.altavista.com/, http://images.google.com/, http://news.yahoo.com/ http://random.yahoo.com/bin/ryl, and
http://lycospro.lycos.com/, to find random web pages.
BUGS
When drawing on the root window, it always uses the default colormap. This is actually a limitation of xv. But regardless, when using
this program with xscreensaver, it must be given the default-n visual specification (see the xscreensaver(1) manual for more details.)
Animating GIFs are not supported: only the first frame will be used.
Too many of the images that it finds are text, not pictures. This is because most of the web is pictures of text. Which is pretty sad.
UPGRADES
The latest version of webcollage can be found as a part of xscreensaver, at http://www.jwz.org/xscreensaver/, or on the WebCollage page at
http://www.jwz.org/webcollage/.
DriftNet: http://www.ex-parrot.com/~chris/driftnet/
SEE ALSO
X(1), xscreensaver(1), xli(1), xv(1), xloadimage(1), ppmmake(1), giftopnm(1), pnmpaste(1), pnmscale(1), djpeg(1), cjpeg(1), xdpyinfo(1),
perl(1), vidwhacker(1), dadadodo(1), driftnet(1) EtherPEG, EtherPeek
COPYRIGHT
Copyright (C) 1998-2002 by Jamie Zawinski. Permission to use, copy, modify, distribute, and sell this software and its documentation for
any purpose is hereby granted without fee, provided that the above copyright notice appear in all copies and that both that copyright
notice and this permission notice appear in supporting documentation. No representations are made about the suitability of this software
for any purpose. It is provided "as is" without express or implied warranty.
AUTHOR
Jamie Zawinski <jwz@jwz.org>, 24-May-98.
X Version 11 17-Jun-99 XScreenSaver(1)