#!/usr/bin/perl -w
# vidwhacker, for xscreensaver. Copyright (c) 1998-2020 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.
#
# This program grabs a frame of video, then uses various pbm filters to
# munge the image in random nefarious ways, then uses xloadimage, xli, or xv
# to put it on the root window. This works out really nicely if you just
# feed some random TV station into it...
#
# Created: 14-Apr-01.
require 5;
use diagnostics;
use strict;
my $progname = $0; $progname =~ s@.*/@@g;
my ($version) = ('$Revision: 1.34 $' =~ m/\s(\d[.\d]+)\s/s);
my $verbose = 0;
my $use_stdin = 0;
my $use_stdout = 0;
my $video_p = 0;
my $file_p = 1;
my $delay = 5;
my $imagedir;
my $screen_width = -1;
my $displayer = "xscreensaver-getimage -root -file";
sub which($);
# apparently some versions of netpbm call it "pamoil" instead of "pgmoil"...
#
my $pgmoil = (which("pamoil") ? "pamoil" : "pgmoil");
# List of interesting PPM filter pipelines.
# In this list, the following magic words may be used:
#
# COLORS a randomly-selected pair of RGB foreground/background colors.
# FILE1 the (already-existing) input PPM file (ok to overwrite it).
# FILE2-FILE4 names of other tmp files you can use.
#
# These commands should read from FILE1, and write to stdout.
# All tmp files will be deleted afterward.
#
my @filters = (
"ppmtopgm FILE1 | pgmedge | pgmtoppm COLORS | ppmnorm",
"ppmtopgm FILE1 | pgmenhance | pgmtoppm COLORS",
"ppmtopgm FILE1 | $pgmoil | pgmtoppm COLORS",
"ppmtopgm FILE1 | pgmbentley | pgmtoppm COLORS",
"ppmrelief FILE1 | ppmtopgm | pgmedge | ppmrelief | ppmtopgm |" .
" pgmedge | pnminvert | pgmtoppm COLORS",
"ppmspread 71 FILE1 > FILE2 ; " .
" pnmarith -add FILE1 FILE2 ; ",
"pnmflip -lr < FILE1 > FILE2 ; " .
" pnmarith -multiply FILE1 FILE2 > FILE3 ; " .
" pnmflip -tb FILE3 | ppmnorm > FILE2 ; " .
" pnmarith -multiply FILE1 FILE2",
"pnmflip -lr FILE1 > FILE2 ; " .
" pnmarith -difference FILE1 FILE2",
"pnmflip -tb FILE1 > FILE2 ; " .
" pnmarith -difference FILE1 FILE2",
"pnmflip -lr FILE1 | pnmflip -tb > FILE2 ; " .
" pnmarith -difference FILE1 FILE2",
"ppmtopgm < FILE1 | pgmedge > FILE2 ; " .
" pnmarith -difference FILE1 FILE2 > FILE3 ; " .
" cp FILE3 FILE1 ; " .
" ppmtopgm < FILE1 | pgmedge > FILE2 ; " .
" pnmarith -difference FILE1 FILE2 > FILE3 ; " .
" ppmnorm < FILE1",
"pnmflip -lr < FILE1 > FILE2 ; " .
" pnmarith -multiply FILE1 FILE2 | ppmrelief | ppmnorm | pnminvert",
"pnmflip -lr FILE1 > FILE2 ; " .
" pnmarith -subtract FILE1 FILE2 | ppmrelief | ppmtopgm | pgmedge",
"pgmcrater -number 20000 -width WIDTH -height HEIGHT FILE1 | " .
" pgmtoppm COLORS > FILE2 ; " .
" pnmarith -difference FILE1 FILE2 > FILE3 ; " .
" pnmflip -tb FILE3 | ppmnorm > FILE2 ; " .
" pnmarith -multiply FILE1 FILE2",
"ppmshift 30 FILE1 | ppmtopgm | $pgmoil | pgmedge | " .
" pgmtoppm COLORS > FILE2 ; " .
" pnmarith -difference FILE1 FILE2",
"ppmpat -madras WIDTH HEIGHT | pnmdepth 255 > FILE2 ; " .
" pnmarith -difference FILE1 FILE2",
"ppmpat -tartan WIDTH HEIGHT | pnmdepth 255 > FILE2 ; " .
" pnmarith -difference FILE1 FILE2",
"ppmpat -camo WIDTH HEIGHT | pnmdepth 255 | ppmshift 50 > FILE2 ; " .
" pnmarith -multiply FILE1 FILE2",
"pgmnoise WIDTH HEIGHT | pgmedge | pgmtoppm COLORS > FILE2 ; " .
" pnmarith -difference FILE1 FILE2 | pnmdepth 255 | pnmsmooth",
);
# Any files on this list will be deleted at exit.
#
my @all_tmpfiles = ();
sub exit_cleanup() {
print STDERR "$progname: delete tmp files\n" if ($verbose);
unlink @all_tmpfiles;
}
sub signal_cleanup() {
my ($sig) = @_;
print STDERR "$progname: caught SIG$sig\n" if ($verbose);
exit 1;
}
sub init_signals() {
$SIG{HUP} = \&signal_cleanup;
$SIG{INT} = \&signal_cleanup;
$SIG{QUIT} = \&signal_cleanup;
$SIG{ABRT} = \&signal_cleanup;
$SIG{KILL} = \&signal_cleanup;
$SIG{TERM} = \&signal_cleanup;
# Need this so that if giftopnm dies, we don't die.
$SIG{PIPE} = 'IGNORE';
}
END { exit_cleanup(); }
# returns the full path of the named program, or undef.
#
sub which($) {
my ($prog) = @_;
foreach (split (/:/, $ENV{PATH})) {
if (-x "$_/$prog") {
return $prog;
}
}
return undef;
}
# Choose random foreground and background colors
#
sub randcolors() {
return sprintf ("#%02x%02x%02x-#%02x%02x%02x",
int(rand()*60),
int(rand()*60),
int(rand()*60),
120+int(rand()*135),
120+int(rand()*135),
120+int(rand()*135));
}
sub filter_subst($$$@) {
my ($filter, $width, $height, @tmpfiles) = @_;
my $colors = randcolors();
$filter =~ s/\bWIDTH\b/$width/g;
$filter =~ s/\bHEIGHT\b/$height/g;
$filter =~ s/\bCOLORS\b/'$colors'/g;
my $i = 1;
foreach my $t (@tmpfiles) {
$filter =~ s/\bFILE$i\b/$t/g;
$i++;
}
if ($filter =~ m/([A-Z]+)/) {
error ("internal error: what is \"$1\"?");
}
$filter =~ s/ +/ /g;
return $filter;
}
# Frobnicate the image in some random way.
#
sub frob_ppm($) {
my ($ppm_data) = @_;
$_ = $ppm_data;
error ("0-length data") if (!defined($ppm_data) || $ppm_data eq "");
error ("not a PPM file") unless (m/^P\d\n/s);
my ($width, $height) = m/^P\d\n(\d+) (\d+)\n/s;
error ("got a bogus PPM") unless ($width && $height);
my $tmpdir = $ENV{TMPDIR};
$tmpdir = "/tmp" unless $tmpdir;
my $fn = sprintf ("%s/vidwhacker-0-%08x", $tmpdir, rand(0xFFFFFFFF));
my $fn1 = sprintf ("%s/vidwhacker-1-%08x", $tmpdir, rand(0xFFFFFFFF));
my $fn2 = sprintf ("%s/vidwhacker-2-%08x", $tmpdir, rand(0xFFFFFFFF));
my $fn3 = sprintf ("%s/vidwhacker-3-%08x", $tmpdir, rand(0xFFFFFFFF));
my @files = ( "$fn", "$fn1", "$fn2", "$fn3" );
push @all_tmpfiles, @files;
my $n = int(rand($#filters+1));
my $filter = $filters[$n];
if ($verbose == 1) {
printf STDERR "$progname: running filter $n\n";
} elsif ($verbose > 1) {
my $f = $filter;
$f =~ s/ +/ /g;
$f =~ s/^ */\t/;
$f =~ s/ *\|/\n\t|/g;
$f =~ s/ *\; */ ;\n\t/g;
print STDERR "$progname: filter $n:\n\n$f\n\n" if $verbose;
}
$filter = filter_subst ($filter, $width, $height, @files);
unlink @files;
local *OUT;
open (OUT, ">$files[0]") || error ("writing $files[0]: $!");
print OUT $ppm_data;
close OUT;
$filter = "( $filter )";
$filter .= "2>/dev/null" unless ($verbose > 1);
local *IN;
open (IN, "$filter |") || error ("opening pipe: $!");
$ppm_data = "";
while (<IN>) { $ppm_data .= $_; }
close IN;
unlink @files;
return $ppm_data;
}
sub read_config() {
my $conf = "$ENV{HOME}/.xscreensaver";
my $had_dir = defined($imagedir);
local *IN;
open (IN, "<$conf") || error ("reading $conf: $!");
while (<IN>) {
if (!$imagedir && m/^imageDirectory:\s+(.*)\s*$/i) { $imagedir = $1; }
elsif (m/^grabVideoFrames:\s+true\s*$/i) { $video_p = 1; }
elsif (m/^grabVideoFrames:\s+false\s*$/i) { $video_p = 0; }
elsif (m/^chooseRandomImages:\s+true\s*$/i) { $file_p = 1; }
elsif (m/^chooseRandomImages:\s+false\s*$/i) { $file_p = 0; }
}
close IN;
$file_p = 1 if $had_dir;
$imagedir = undef unless ($imagedir && $imagedir ne '');
if (!$file_p && !$video_p) {
# error ("neither grabVideoFrames nor chooseRandomImages are set\n\t") .
# "in $conf; $progname requires one or both."
$file_p = 1;
}
if ($file_p) {
error ("no imageDirectory set in $conf") unless $imagedir;
error ("imageDirectory $imagedir doesn't exist") unless (-d $imagedir);
}
if ($verbose > 1) {
printf STDERR "$progname: grab video: $video_p\n";
printf STDERR "$progname: grab images: $file_p\n";
printf STDERR "$progname: directory: $imagedir\n";
}
}
sub get_ppm() {
if ($use_stdin) {
print STDERR "$progname: reading from stdin\n" if ($verbose > 1);
my $ppm = "";
while (<STDIN>) { $ppm .= $_; }
return $ppm;
} else {
my $do_file_p;
if ($file_p && $video_p) {
$do_file_p = (int(rand(2)) == 0);
print STDERR "$progname: doing " . ($do_file_p ? "files" : "video") ."\n"
if ($verbose);
}
elsif ($file_p) { $do_file_p = 1; }
elsif ($video_p) { $do_file_p = 0; }
else {
error ("internal error: not grabbing files or video?");
}
my $v = ($verbose <= 1 ? "" : "-" . ("v" x ($verbose-1)));
my $cmd;
if ($do_file_p) {
$cmd = "xscreensaver-getimage-file $v --name \"$imagedir\"";
} else {
$cmd = "xscreensaver-getimage-video $v";
}
my $ppm;
print STDERR "$progname: running: $cmd\n" if ($verbose > 1);
my $fn = `$cmd`;
$fn =~ s/\n$//s;
error ("didn't get a file?") if ($fn eq "");
$fn = "$imagedir/$fn" unless ($fn =~ m@^/@s);
print STDERR "$progname: selected file $fn\n" if ($verbose > 1);
if ($fn =~ m/\.gif/i) { $cmd = "giftopnm < \"$fn\""; }
elsif ($fn =~ m/\.jpe?g/i) { $cmd = "exiftran -o /dev/stdout -a \"$fn\" | djpeg"; }
elsif ($fn =~ m/\.png/i) { $cmd = "pngtopnm < \"$fn\""; }
elsif ($fn =~ m/\.xpm/i) { $cmd = "xpmtoppm < \"$fn\""; }
elsif ($fn =~ m/\.bmp/i) { $cmd = "bmptoppm < \"$fn\""; }
elsif ($fn =~ m/\.tiff?/i) { $cmd = "tifftopnm < \"$fn\""; }
elsif ($fn =~ m/\.p[bgp]m/i) { $cmd = "cat \"$fn\""; }
else {
print STDERR "$progname: $fn: unrecognized file extension\n";
# go around the loop and get another
return undef;
}
print STDERR "$progname: converting with: $cmd\n" if ($verbose > 1);
$cmd .= " 2>/dev/null" unless ($verbose > 1);
$ppm = `$cmd`;
unlink $fn if (!$do_file_p);
return $ppm;
}
}
sub dispose_ppm($) {
my ($ppm) = @_;
error ("0-length data") if (!defined($ppm) || $ppm eq "");
error ("not a PPM file") unless ($ppm =~ m/^P\d\n/s);
if ($use_stdout) {
print STDERR "$progname: writing to stdout\n" if ($verbose > 1);
print $ppm;
} else {
my $tmpdir = $ENV{TMPDIR};
$tmpdir = "/tmp" unless $tmpdir;
my $fn = sprintf ("%s/vidwhacker-%08x.ppm", $tmpdir, rand(0xFFFFFFFF));
local *OUT;
unlink $fn;
push @all_tmpfiles, $fn;
open (OUT, ">$fn") || error ("writing $fn: $!");
print OUT $ppm;
close OUT;
my @cmd = split (/ +/, $displayer);
push @cmd, $fn;
print STDERR "$progname: executing \"" . join(" ", @cmd) . "\"\n"
if ($verbose);
system (@cmd);
my $exit_value = $? >> 8;
my $signal_num = $? & 127;
my $dumped_core = $? & 128;
unlink $fn;
error ("$cmd[0]: core dumped!") if ($dumped_core);
error ("$cmd[0]: signal $signal_num!") if ($signal_num);
error ("$cmd[0]: exited with $exit_value!") if ($exit_value);
}
}
my $stdin_ppm = undef;
sub vidwhack() {
my $ppm;
if ($use_stdin) {
if (!defined($stdin_ppm)) {
$stdin_ppm = get_ppm();
}
$ppm = $stdin_ppm;
} else {
my $max_err_count = 20;
my $err_count = 0;
while (!defined($ppm)) {
$ppm = get_ppm();
if (!defined ($ppm)) {
$err_count++
} else {
$ppm = frob_ppm ($ppm);
undef $ppm if (defined ($ppm) && $ppm eq "");
$err_count++ if (!defined ($ppm));
};
error ("too many errors, too few images!")
if ($err_count > $max_err_count);
}
}
dispose_ppm ($ppm);
$ppm = undef;
}
sub error($) {
my ($err) = @_;
print STDERR "$progname: $err\n";
exit 1;
}
sub usage() {
print STDERR "VidWhacker, Copyright (c) 2001 Jamie Zawinski <jwz\@jwz.org>\n";
print STDERR " https://www.jwz.org/xscreensaver/";
print STDERR "\n";
print STDERR "usage: $0 [-display dpy] [-verbose]\n";
print STDERR "\t\t[-root | -window | -window-id 0xXXXXX ]\n";
print STDERR "\t\t[-stdin] [-stdout] [-delay secs]\n";
print STDERR "\t\t[-directory image_directory]\n";
exit 1;
}
sub main() {
while ($_ = $ARGV[0]) {
shift @ARGV;
if (m/^--?verbose$/) { $verbose++; }
elsif (m/^-v+$/) { $verbose += length($_)-1; }
elsif (m/^(-display|-disp|-dis|-dpy|-d)$/) { $ENV{DISPLAY} = shift @ARGV; }
elsif (m/^--?stdin$/) { $use_stdin = 1; }
elsif (m/^--?stdout$/) { $use_stdout = 1; }
elsif (m/^--?delay$/) { $delay = shift @ARGV; }
elsif (m/^--?dir(ectory)?$/) { $imagedir = shift @ARGV; }
elsif (m/^--?root$/) { }
elsif (m/^--?window-id$/) {
my $id = shift @ARGV;
error ("unparsable window id: $id")
unless ($id =~ m/^\d+$|^0x[\da-f]+$/i);
$displayer =~ s/--?root\b/$id/ ||
error ("unable to munge displayer: $displayer");
}
elsif (m/^--?window$/) {
print STDERR "$progname: sorry, \"-window\" is unimplemented.\n";
print STDERR "$progname: use \"-stdout\" and pipe to a displayer.\n";
exit 1;
}
elsif (m/^-./) { usage; }
else { usage; }
}
init_signals();
read_config;
# sanity checking - is pbm installed?
# (this is a non-exhaustive but representative list)
foreach ("ppmtopgm", "pgmenhance", "pnminvert", "pnmarith", "pnmdepth") {
which ($_) || error "$_ not found on \$PATH.";
}
if (!$use_stdout) {
$_ = `xdpyinfo 2>&-`;
($screen_width) =~ m/ dimensions: +(\d+)x(\d+) pixels/;
$screen_width = 800 unless $screen_width > 0;
}
if ($use_stdout) {
vidwhack();
} else {
while (1) {
vidwhack();
sleep $delay;
}
}
}
main();
exit 0;
