From http://www.jwz.org/xscreensaver/xscreensaver-5.23.tar.gz

[xscreensaver] / driver / xscreensaver-getimage-video

diff --git a/driver/xscreensaver-getimage-video b/driver/xscreensaver-getimage-video
index 15c5a9ef6e3aefe28de4dffebd317cf75ecd61fc..cc8d99d3545196cf590d16c91d8398d6805cddb7 100755 (executable)
--- a/driver/xscreensaver-getimage-video
+++ b/driver/xscreensaver-getimage-video
@@ -1,5 +1,5 @@
 #!/usr/bin/perl -w
-# Copyright © 2001, 2002, 2003, 2005 Jamie Zawinski <jwz@jwz.org>.
+# Copyright © 2001-2013 Jamie Zawinski <jwz@jwz.org>.
 #
 # Permission to use, copy, modify, distribute, and sell this software and its
 # documentation for any purpose is hereby granted without fee, provided that
@@ -18,23 +18,24 @@
 # "jigsaw", etc.) get the image to manipulate by running the
 # "xscreensaver-getimage" program.
 #
-# "xscreensaver-getimage" will invoke this program, depending on the
-# value of the "grabVideoFrames" setting in the ~/.xscreensaver file
-# (or in /usr/lib/X11/app-defaults/XScreenSaver).
+# The various screen savers invoke "xscreensaver-getimage", which will in
+# turn invoke this program, depending on the value of the "grabVideoFrames"
+# setting in the ~/.xscreensaver file (or in the app-defaults file, usually
+# /usr/lib/X11/app-defaults/XScreenSaver).
 #
 # Created: 13-Apr-2001.
 
 require 5;
-use diagnostics;
+#use diagnostics;      # Fails on some MacOS 10.5 systems
 use strict;
 
 my $progname = $0; $progname =~ s@.*/@@g;
-my $version = q{ $Revision: 1.13 $ }; $version =~ s/^[^0-9]+([0-9.]+).*$/$1/;
+my $version  = q{ $Revision: 1.22 $ }; $version =~ s/^[^0-9]+([0-9.]+).*$/$1/;
 
-my $verbose = 0;
+my $tmpdir   = $ENV{TMPDIR} || "/tmp";
+my $tmpfile  = sprintf("%s/xssv.%08x.ppm", $tmpdir, rand(0xFFFFFFFF));
 
-my $tmpdir  = $ENV{TMPDIR} || "/tmp";
-my $tmpfile = sprintf ("%s/xssgv.%08x.ppm", $tmpdir, rand(0xFFFFFFFF));
+my $verbose = 0;
 
 
 # These are programs that can be used to grab a video frame.  The first one
@@ -50,6 +51,8 @@ my @programs = (
   "qcam > $tmpfile",                           # Connectix Qcam
   "gqcam -t PPM -d $tmpfile",                  # GTK+ Qcam clone
 
+  "v4lctl snap ppm full $tmpfile",             # XawTV 3.94.
+
   "streamer -a -s 768x576 -o $tmpfile",                # XawTV
   #   the "-a" option ("mute audio") arrived with XawTV 3.76.
 
@@ -65,18 +68,21 @@ my @programs = (
 
   "vidtomem -f $tmpfile 2>&- " .               # Silicon Graphics
        "&& mv $tmpfile-00000.rgb $tmpfile",
+
+  # "mplayer -really-quiet tv://0 " .          # Maybe works with some cams?
+  #         "-ao null -vo pnm -frames 1 2>&- " .
+  #    "&& mv 00000001.ppm $tmpfile",
+
 );
 
 
-sub error {
-  ($_) = @_;
-  print STDERR "$progname: $_\n";
+sub error($) {
+  my ($e) = @_;
+  print STDERR "$progname: $e\n";
   exit 1;
 }
 
-my $displayer = undef;
-
-sub pick_grabber {
+sub pick_grabber() {
   my @names = ();
 
   foreach my $cmd (@programs) {
@@ -87,86 +93,47 @@ sub pick_grabber {
     foreach my $dir (split (/:/, $ENV{PATH})) {
       print STDERR "$progname:   checking $dir/$name\n" if ($verbose > 3);
       if (-x "$dir/$name") {
-        $displayer = $name;
         return $cmd;
       }
     }
   }
 
   $names[$#names] = "or " . $names[$#names];
-  error "none of: " . join (", ", @names) . " were found on \$PATH.";
+  error ("none of: " . join (", ", @names) . " were found on \$PATH.");
 }
 
 
-my $use_stdout_p = 0;
-my $return_filename_p = 0;
-
-sub grab_image {
+sub grab_image() {
   my $cmd = pick_grabber();
   unlink $tmpfile;
 
   print STDERR "$progname: executing \"$cmd\"\n" if ($verbose);
   system ($cmd);
 
-  if (-z $tmpfile)
-    {
-      unlink $tmpfile;
-      error "\"$cmd\" produced no data.";
-    }
-
-  if ($return_filename_p) {
-    print STDERR "$progname: wrote \"$tmpfile\"\n" if ($verbose);
-    print STDOUT "$tmpfile\n";
-
-  } elsif ($use_stdout_p) {
-    local *IN;
-    my $ppm = "";
-    my $reader  = "<$tmpfile";
-
-    # horrid kludge for SGIs, since they don't use PPM...
-    if ($displayer eq "vidtomem") {
-      $reader = "sgitopnm $tmpfile";
-      $reader .= " 2>/dev/null" if ($verbose <= 1);
-      $reader .= " |";
-    }
-
-    open(IN, $reader) || error "reading $tmpfile: $!";
-    print STDERR "$progname: reading $tmpfile\n" if ($verbose > 1);
-    while (<IN>) { $ppm .= $_; }
-    close IN;
-    unlink $tmpfile;
-    print STDOUT $ppm;
-
-  } else {
-
-    $cmd = "xscreensaver-getimage-file";
-    $cmd .= " --verbose" if ($verbose);
-    $cmd .= " $tmpfile";
-
-    print STDERR "$progname: executing \"$cmd\"\n" if ($verbose);
-    system ($cmd);
-
+  if (! -s $tmpfile) {
     unlink $tmpfile;
+    error ("\"$cmd\" produced no data.");
   }
+
+  print STDERR "$progname: wrote \"$tmpfile\"\n" if ($verbose);
+  print STDOUT "$tmpfile\n";
 }
 
 
-sub usage {
+sub usage() {
   print STDERR "usage: $progname [--verbose] [--name | --stdout]\n";
   exit 1;
 }
 
-sub main {
+sub main() {
   while ($_ = $ARGV[0]) {
     shift @ARGV;
-    if ($_ eq "--verbose") { $verbose++; }
-    elsif (m/^-v+$/) { $verbose += length($_)-1; }
-    elsif (m/^--?stdout$/) { $use_stdout_p = 1; }
-    elsif (m/^--?name$/)   { $return_filename_p = 1; }
-    elsif (m/^-./) { usage; }
-    else { usage; }
+    if    (m/^--?verbose$/s) { $verbose++; }
+    elsif (m/^-v+$/s)        { $verbose += length($_)-1; }
+    elsif (m/^--?name$/s)    { }   # ignored, for compatibility
+    elsif (m/^-./)           { usage; }
+    else                     { usage; }
   }
-
   grab_image();
 }