[ViewVC] Annotation of: cvs/cvsroot/CV/bin/cv

#!/opt/bin/perl

use common::sense;

use Cwd ();
use Encode ();
use File::Glob ();
use Scalar::Util ();

use Gtk2 -init;
use Gtk2::Gdk::Keysyms;

use Gtk2::CV;

use Gtk2::CV::ImageWindow;
use Gtk2::CV::Schnauzer;

BEGIN {
   require Gtk2::CV::Plugin;
   require "$ENV{HOME}/.cvrc" if -r "$ENV{HOME}/.cvrc";
}

use Carp (); $Carp::MaxArgLen = 256;#d#

use Gtk2::CV::Plugin::NameCluster;
use Gtk2::CV::Plugin::RCluster;
use Gtk2::CV::Plugin::PatRenamer;

Gtk2::CV::Jobber::start_slaves;

Gtk2::Rc->parse (Gtk2::CV::find_rcfile "gtkrc");

use File::Spec;

my $mainwin;
my $viewer;
my $viewer_count;
my $schnauzer;
my $info;
my $help;

my $schnauzer_idx = 0;

sub new_schnauzer {
   my $s = new Gtk2::CV::Schnauzer;

   $s->signal_connect_after (key_press_event => \&std_keys);
   $s->signal_connect (activate => sub {
      my $label = sprintf "%s (%d)",
                  (Glib::filename_display_name +(File::Spec->splitpath ($_[1]))[2]),
                  -s $_[1];
      $info->set_label ($label);
      $viewer->load_image ($_[1]) if $viewer; # TODO: error, or chose ANY viewer
   });

   Gtk2::CV::Plugin->call (new_schnauzer => $s);

   $s
}

our %VIEWER; # global viewer container so we can propagate signals

$SIG{USR1} = sub {
   # I assume glib calls us in a safe enough context to create an idle watcher
   add Glib::Idle sub {
      $_->reload for values %VIEWER;
      0
   };
};

sub new_viewer {
   my $self = new Gtk2::CV::ImageWindow;

   Scalar::Util::weaken ($VIEWER{$self+0} = $self);

   $viewer_count++;

   $self->set_title ("CV: Image");

   $self->signal_connect (key_press_event => sub {
      $viewer = $_[0];

      my $key = $_[1]->keyval;
      my $state = $_[1]->state;

      if ($state * "control-mask" && $key == $Gtk2::Gdk::Keysyms{c}) {
         my $viewer = new_viewer ();
         $viewer->set_image ($_[0]->{image});
         $viewer->show_all;
         1
      } else {
         &std_keys
            or $schnauzer->signal_emit (key_press_event => $_[1])
      }
   });
   $self->signal_connect (delete_event => sub { $_[0]->destroy; 0 });
   $self->signal_connect (destroy => sub {
      delete $VIEWER{$_[0]+0};
      $viewer = undef if $viewer == $_[0];

      main_quit Gtk2 unless --$viewer_count;

      0
   });

   $self->signal_connect (button3_press_event => sub {
      $mainwin->visible
         ? $mainwin->hide
         : $mainwin->show_all;

      1
   });

   Gtk2::CV::Plugin->call (new_imagewindow => $self);

   $self
}

sub std_keys {
   my $key = $_[1]->keyval;
   my $state = $_[1]->state;

   my $ctrl = $state * "control-mask";

   if ($key == $Gtk2::Gdk::Keysyms{q}) {
      $viewer->destroy;
   } elsif ($ctrl && $key == $Gtk2::Gdk::Keysyms{v}) {
      my $w = new Gtk2::Window;

      $w->set_role ("schnauzer");
      $w->set_title ("CV: Schnauzer");
      $w->add (my $s = new_schnauzer);
      $s->set_dir (File::Spec->curdir);
      $s->set_geometry_hints;
      $w->show_all;

   } elsif ($ctrl && $key == $Gtk2::Gdk::Keysyms{h}) {
      unless ($help) {
         require Gtk2::Ex::PodViewer;

         $help = new Gtk2::Window;
         $help->set_role ("help");
         $help->set_title ("CV: Help");
         $help->set_default_size (500, 300);
         $help->signal_connect (delete_event => sub { $help->hide; 1 });

         $help->add (my $sw = new Gtk2::ScrolledWindow);
         $sw->add (my $h = new Gtk2::Ex::PodViewer);

         #binmode DATA, ":utf8";
         $h->load_string (do { local $/; <DATA> });
      }

      $help->show_all;
   } elsif (!$state && $Gtk2::Gdk::Keysyms{a} <= $key && $key <= $Gtk2::Gdk::Keysyms{z}) {
      #
   } else {
      return 0;
   }

   1
}

{
   $viewer = new_viewer;
   $::cur_viewer = $viewer;

   $schnauzer = new_schnauzer;

   $mainwin = new Gtk2::Window;
   $mainwin->set_role ("main");
   $mainwin->set_title ("CV");
   $mainwin->add (my $vbox = new Gtk2::VBox);
   $mainwin->signal_connect (delete_event => sub { $mainwin->hide; 1 });

   $vbox->add ($schnauzer);
   $vbox->pack_end (my $frame = new Gtk2::Frame, 0, 0, 0);
   $frame->add (my $hbox = new Gtk2::HBox 0, 0);
   $hbox->pack_start ((new Gtk2::Label "Info: "), 0, 0, 0);
   $hbox->pack_end   (my $labelwindow = new Gtk2::EventBox, 1, 1, 0);
   $labelwindow->add ($info = new Gtk2::Label);
   $labelwindow->signal_connect_after (size_request => sub { $_[1]->width (0); 0 });
   $info->set (selectable => 1, xalign => 0, justify => "left");

   $schnauzer->set_geometry_hints;
}

if (@ARGV) {
   my $show_first = sub {
      $schnauzer->show_all;
      $schnauzer->handle_key ($Gtk2::Gdk::Keysyms{space}, []);
      $viewer->show_all;
   };

   if (@ARGV == 1 && $ARGV[0] eq "-0r") {
      local $/;
      $schnauzer->set_paths ([split /\x00/, <STDIN>], 1, $show_first);
   } elsif (@ARGV == 1 && -d $ARGV[0]) {
      $schnauzer->set_dir (shift, $show_first);
   } else {
      if ($ARGV[0] eq "-g") {
         shift @ARGV;
         @ARGV = map +(File::Glob::bsd_glob $_, File::Glob::GLOB_BRACE | File::Glob::GLOB_QUOTE), @ARGV;
      }
      $schnauzer->set_paths ([@ARGV], 1, $show_first);
   }
} else {
   $schnauzer->set_dir (File::Spec->curdir, sub {
      $mainwin->show_all;
      $viewer->show_all;
   });
}

main Gtk2;

Gtk2::CV::flush_aio;

__DATA__

=encoding utf-8

=head1 NAME

cv - a fast gtk+ image viewer loosely modeled after XV

=head1 SYNOPSIS

   cv [file...]

=head1 FEATURES

CV is supposed to work similar to the venerable XV image viewer, just
faster. Why faster?

=over 4

=item * optimized directory scanning algorithm

The directory scanning in CV uses some tricks that - on most modern
filesystems - makes it possible to detect filetypes faster than stat()'ing
every file. This makes CV suitable for directories with lots of files
(10000+).

This algorithm is quite unprecise - it doesn't make a difference between
files, device nodes, symlinks and the like, and filetype detection is done
using the file extension only.

On the positive side, it is usually many orders of magnitude faster than
traditional scanning techniques (good for directories with 10000 or
100000+ files).

=item * queuing for all time-consuming background tasks

All tasks, such as unlinking files or generating thumbnails, that can be
done in the background will be done so - no waiting required, even when
changing directories.

=item * use of asynchronous I/O

CV tries to use asynchronous I/O whereever it makes sense, for example
while scanning directories, waiting for stat data, unlinking files or
generating thumbnails. This usually decreases scanning times for large
directories a bit (especially on RAID devices and over NFS) and makes CV
much more interactive.

=item * fast image loading

The time span between the user issuing a command and displaying the new
image should be as small as possible. CV uses optimized (especially
for JPEG) loading functions and sacrifices some quality (e.g no gamma
correction, although this might change) to achieve this speed.

=item * fast thumbnail creation

Thumbnail creation uses both CPU and Disk-I/O. CV interleaves both, so
on modern CPUs, thumbnailing is usually limited by I/O speed. Thumbnail
creation for JPEGs has been specially optimized and can even take
advantage of multiple CPUs.

=item * minimum optical clutter

CV has no menus or other user interface elements that take up a lot of
screen space (or are useful for beginning users). The schnauzer windows
can also be somewhat crowded.

The point of an image viewer is viewing images, not a nice GUI. This is
similar to XV's behaviour.

=item * efficient (and hard to learn) user interface

CV uses key combinations. A lot. If you are an experienced XV user, you
will find most of these keys familiar. If not, CV might be hard to use at
first, but will be an efficient tool later.

=item * multi-window GUI

CV doesn't force you to use a specific layout, instead it relies on your
window manager, thus enabling you to chose whatever layout that suits you
most.

=item * i18n'ed filename handling throughout

As long as glib can recognize your filename encoding (either UTF-8 or
locale-specific, depending on the setting of G_BROKEN_FILENAMES) and you
have the relevant fonts, CV will display your filenames correctly.

=item * extensible through plug-ins

I have weird plug-ins that access remote databases to find a
directory. This is not likely to be of any use to other people. Likewise,
others might have weird requirements I cannot dream of.

=item * filename clustering

Among the standard plug-ins is a filename clustering plug-in, that (in
case of tens of thousands images in one directory) might be able to
cluster similar names together.

=back

=head1 DESCRIPTION

=head2 THE IMAGE WINDOW

You can use the following keys in the image window:

 q            quit the program
 <            half the image size
 >            double the image size
 ,            shrink the image by 10%
 .            enlarge the image by 10%
 n            reset to normal size
 m            maximize to screensize
 M            maximize to screensize, respecting image aspect
 ctrl-m       toggle maxpect-always mode
 ctrl-sift-m  toggle using current image size as max image size
 u            uncrop
 r            set scaling mode to 'nearest' (fastest)
 s            set scaling mode to 'bilinear' (default)
 shift-s      set scaling mode to 'hyper' (slowest)
 t            rotate clockwise 90°
 T            rotate counterclockwise°
 a            apply all rotations loslessly to a jpeg file (using exiftran)
 ctrl-v       open a new visual schnauzer window for the current dir
 ctrl-c       clone the current image window
 ctrl-e       run an editor ($CV_EDITOR or "gimp") on the current image
 ctrl-p       fire up the print dialog
 escape       cancel a crop action

And when playing movies, these additional keys are active:

 left         rewind by 10 seconds
 right        forward by 10 seconds
 down         rewind by 60 seconds
 up           forward by 60 seconds
 pg_up        rewind by 600 seconds
 pg_down      forward by 600 seconds
 o            toggle on-screen display
 p            pause/unpause
 escape       stop playing
 9            turn volume down
 0            turn volume up

Any other keys will be sent to the default schnauzer window, which can be
toggled on and off by right-clicking into the image window.

Left-clicking into the image window will let you crop the image (usually
to zoom into large images that CV scales down).

=head2 THE VISUAL SCHNAUZER

Any image-loading action in a schnauzer window acts on the
"last-recently-activated" imagewindow, which currently is simply the last
image window that received a keypress.

You can use the following keys in the schnauzer window:

 ctrl-space,
 space        move to and display next image
 ctrl-backspace,
 backspace    move to and display previous image
 ctrl-return,
 return       display selected picture, or enter directory

 cursor keys  move selection
 page-up      move one page up
 page-down    move one page down
 home         move to first file
 end          move to last file

 ctrl-a       select all files
 ctrl-shift-a select all files currently displayed in the schnauzer window
 ctrl-d       delete selected files WITHOUT ASKING AGAIN
 ctrl-g       force generation of thumbnais for the selected files
 ctrl-s       rescan current direcory or files updates/deletes etc.
 ctrl-u       update selected (or all) icons if neccessary
 ctrl--       unselected thumbnailed images
 ctrl-+       keep only thumbnailed images, deselect others

 ^            go to parent directory (caret).

 0-9,
 a-z          find the first filename beginning with this letter

Right-clicking into the schnauzer window displays a pop-up menu with
additional actions.

=head3 SELECTION

You can select entries in the Schnauzer in a variety of ways:

=over 4

=item Keyboard

Moving the cursor with the keyboard will first deselect all files and then
select the file you moved to.

=item Clicking

Clicking on an entry will select the one you clicked and deselect all
others.

=item Shift-Clicking

Shift-clicking will toggle the selection on the entry under the mouse.

=item Dragging

Dragging will select all entries between the one selected when pushing the
button and the one selected when releasing the button. If you move above
or below the schnauzer area while drag-selecting, the schnauzer will move
up/down one row twice per second. In addition, horizontal mouse movement
acts as a kind of invisible horizontal scrollbar.

=item Hint: double-click works while click-selecting

You can double-click any image while click-selecting to display it
without stopping the selection process. This will act as if you normally
double-clicked the image to display it, and will toggle the selection
twice, resulting in no change.

=back

=head1 FILES

When starting, CV runs the F<.cvrc> file in your F<$HOME> directory as if
it were a perl script. in that, you will mostly load plug-ins.

Example:

   system "fping -q -t 10 ether"
     or require "/fs/cv/cvplugin.pl";

This will load a plug-in, but only if the machine I<ether> is reachable
(supposedly the plug-in is networked in some way :).

=head1 ENVIRONMENT VARIABLES

=over 4

=item CV_EDITOR

The program that gets executed when the user presses C<CTRL-e> in the
Schnauzer or image window. The default is C<gimp>.

=item CV_AUDIO_PLAYER

Program used to play all sorts of audio (wav, aif, mp3, ogg...), default "play".
Will be called like C<< $CV_AUDIO_PLAYER -- <path> >>.

=item CV_PRINT_DESTINATION

The default (perl-style) destination to use in the print dialog.

=item CV_TRASHCAN

When set, must point to a directory where all files that are deleted by
the "Delete Physically" (ctrl-d) action are moved to (other deletion
actions still delete!). If unset, files that are deleted are really being
deleted.

=back

=head1 SIGNALS

Sending CV a SIGUSR1 signal will cause all image viewers to reload the
currently loaded image. This is useful if you use CV as a viewer for
changing data - just run it in the background with some path and each time
the image changes, send it a SIGUSR1.

=head1 SECURITY CONSIDERATIONS

CV uses Pixbuf to load non-JPEG images. Pixbuf is not considered safe for
this purpose, though (from the gtk-2.2 release notes):

"While efforts have been made to make gdk-pixbuf robust against invalid
images, using gdk-pixbuf to load untrusted data is not recommended, due to
the likelyhood that there are additional problems where an invalid image
could cause gdk-pixbuf to crash or worse."

=head1 BUGS/TODO

 Lots of functionality is missing.

 Pixbuf doesn't always honor G_BROKEN_FILENAMES, so accessing files with
 names incompatible with utf-8 might fail.

 rotate on disk
 lots of ui issues
 save(?)
 preferences

=head1 AUTHOR

Marc Lehmann <cv@plan9.de>.

=cut

Revision:	1.83
Committed:	Mon Feb 20 01:58:56 2012 UTC (14 years, 7 months ago) by root
Branch:	MAIN
Changes since 1.82:	+1 -1 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	#!/opt/bin/perl
2
3	root	1.80	use common::sense;
4
5	root	1.37	use Cwd ();
6			use Encode ();
7	root	1.72	use File::Glob ();
8	root	1.79	use Scalar::Util ();
9	root	1.37
10	root	1.12	use Gtk2 -init;
11			use Gtk2::Gdk::Keysyms;
12
13	root	1.48	use Gtk2::CV;
14
15	root	1.12	use Gtk2::CV::ImageWindow;
16			use Gtk2::CV::Schnauzer;
17
18	root	1.48	BEGIN {
19			require Gtk2::CV::Plugin;
20			require "$ENV{HOME}/.cvrc" if -r "$ENV{HOME}/.cvrc";
21			}
22
23	root	1.82	use Carp (); $Carp::MaxArgLen = 256;#d#
24
25	root	1.48	use Gtk2::CV::Plugin::NameCluster;
26			use Gtk2::CV::Plugin::RCluster;
27	root	1.81	use Gtk2::CV::Plugin::PatRenamer;
28	root	1.16
29	root	1.77	Gtk2::CV::Jobber::start_slaves;
30
31	root	1.16	Gtk2::Rc->parse (Gtk2::CV::find_rcfile "gtkrc");
32
33	root	1.20	use File::Spec;
34
35			my $mainwin;
36	root	1.12	my $viewer;
37	root	1.62	my $viewer_count;
38	root	1.12	my $schnauzer;
39	root	1.20	my $info;
40	root	1.21	my $help;
41	root	1.12
42	root	1.25	my $schnauzer_idx = 0;
43
44	root	1.12	sub new_schnauzer {
45	root	1.20	my $s = new Gtk2::CV::Schnauzer;
46	root	1.12
47			$s->signal_connect_after (key_press_event => \&std_keys);
48	root	1.20	$s->signal_connect (activate => sub {
49			my $label = sprintf "%s (%d)",
50	root	1.75	(Glib::filename_display_name +(File::Spec->splitpath ($_[1]))[2]),
51	root	1.20	-s $_[1];
52			$info->set_label ($label);
53	root	1.62	$viewer->load_image ($_[1]) if $viewer; # TODO: error, or chose ANY viewer
54	root	1.20	});
55	root	1.12
56	root	1.40	Gtk2::CV::Plugin->call (new_schnauzer => $s);
57
58	root	1.53	$s
59	root	1.12	}
60
61	root	1.79	our %VIEWER; # global viewer container so we can propagate signals
62
63			$SIG{USR1} = sub {
64			# I assume glib calls us in a safe enough context to create an idle watcher
65			add Glib::Idle sub {
66			$_->reload for values %VIEWER;
67			0
68			};
69			};
70
71	root	1.62	sub new_viewer {
72			my $self = new Gtk2::CV::ImageWindow;
73
74	root	1.79	Scalar::Util::weaken ($VIEWER{$self+0} = $self);
75
76	root	1.62	$viewer_count++;
77
78			$self->set_title ("CV: Image");
79
80			$self->signal_connect (key_press_event => sub {
81			$viewer = $_[0];
82
83			my $key = $_[1]->keyval;
84			my $state = $_[1]->state;
85
86			if ($state * "control-mask" && $key == $Gtk2::Gdk::Keysyms{c}) {
87			my $viewer = new_viewer ();
88			$viewer->set_image ($_[0]->{image});
89			$viewer->show_all;
90			1
91			} else {
92			&std_keys
93			or $schnauzer->signal_emit (key_press_event => $_[1])
94			}
95			});
96	root	1.63	$self->signal_connect (delete_event => sub { $_[0]->destroy; 0 });
97	root	1.62	$self->signal_connect (destroy => sub {
98	root	1.79	delete $VIEWER{$_[0]+0};
99	root	1.62	$viewer = undef if $viewer == $_[0];
100
101			main_quit Gtk2 unless --$viewer_count;
102	root	1.63
103			0
104	root	1.62	});
105
106			$self->signal_connect (button3_press_event => sub {
107			$mainwin->visible
108			? $mainwin->hide
109			: $mainwin->show_all;
110	root	1.63
111	root	1.62	1
112			});
113
114			Gtk2::CV::Plugin->call (new_imagewindow => $self);
115
116			$self
117			}
118
119	root	1.12	sub std_keys {
120			my $key = $_[1]->keyval;
121			my $state = $_[1]->state;
122
123	root	1.21	my $ctrl = $state * "control-mask";
124	root	1.12
125			if ($key == $Gtk2::Gdk::Keysyms{q}) {
126	root	1.62	$viewer->destroy;
127	root	1.12	} elsif ($ctrl && $key == $Gtk2::Gdk::Keysyms{v}) {
128	root	1.20	my $w = new Gtk2::Window;
129	root	1.26
130	root	1.66	$w->set_role ("schnauzer");
131	root	1.26	$w->set_title ("CV: Schnauzer");
132	root	1.20	$w->add (my $s = new_schnauzer);
133			$s->set_dir (File::Spec->curdir);
134	root	1.25	$s->set_geometry_hints;
135	root	1.21	$w->show_all;
136	root	1.25
137	root	1.21	} elsif ($ctrl && $key == $Gtk2::Gdk::Keysyms{h}) {
138			unless ($help) {
139	root	1.73	require Gtk2::Ex::PodViewer;
140	root	1.21
141			$help = new Gtk2::Window;
142	root	1.67	$help->set_role ("help");
143	root	1.26	$help->set_title ("CV: Help");
144	root	1.21	$help->set_default_size (500, 300);
145			$help->signal_connect (delete_event => sub { $help->hide; 1 });
146
147			$help->add (my $sw = new Gtk2::ScrolledWindow);
148	root	1.73	$sw->add (my $h = new Gtk2::Ex::PodViewer);
149	root	1.21
150			#binmode DATA, ":utf8";
151			$h->load_string (do { local $/; <DATA> });
152			}
153
154			$help->show_all;
155	root	1.83	} elsif (!$state && $Gtk2::Gdk::Keysyms{a} <= $key && $key <= $Gtk2::Gdk::Keysyms{z}) {
156	root	1.82	#
157	root	1.12	} else {
158	root	1.43	return 0;
159	root	1.12	}
160
161	root	1.43	1
162	root	1.12	}
163
164	root	1.20	{
165	root	1.62	$viewer = new_viewer;
166			$::cur_viewer = $viewer;
167	root	1.40
168	root	1.20	$schnauzer = new_schnauzer;
169
170			$mainwin = new Gtk2::Window;
171	root	1.66	$mainwin->set_role ("main");
172	root	1.20	$mainwin->set_title ("CV");
173			$mainwin->add (my $vbox = new Gtk2::VBox);
174	root	1.53	$mainwin->signal_connect (delete_event => sub { $mainwin->hide; 1 });
175	root	1.20
176			$vbox->add ($schnauzer);
177	root	1.22	$vbox->pack_end (my $frame = new Gtk2::Frame, 0, 0, 0);
178	root	1.20	$frame->add (my $hbox = new Gtk2::HBox 0, 0);
179	root	1.45	$hbox->pack_start ((new Gtk2::Label "Info: "), 0, 0, 0);
180			$hbox->pack_end (my $labelwindow = new Gtk2::EventBox, 1, 1, 0);
181			$labelwindow->add ($info = new Gtk2::Label);
182			$labelwindow->signal_connect_after (size_request => sub { $_[1]->width (0); 0 });
183			$info->set (selectable => 1, xalign => 0, justify => "left");
184	root	1.25
185			$schnauzer->set_geometry_hints;
186	root	1.20	}
187	root	1.12
188			if (@ARGV) {
189	root	1.68	my $show_first = sub {
190			$schnauzer->show_all;
191			$schnauzer->handle_key ($Gtk2::Gdk::Keysyms{space}, []);
192			$viewer->show_all;
193			};
194
195	root	1.71	if (@ARGV == 1 && $ARGV[0] eq "-0r") {
196			local $/;
197	root	1.74	$schnauzer->set_paths ([split /\x00/, <STDIN>], 1, $show_first);
198	root	1.71	} elsif (@ARGV == 1 && -d $ARGV[0]) {
199	root	1.74	$schnauzer->set_dir (shift, $show_first);
200	root	1.71	} else {
201	root	1.72	if ($ARGV[0] eq "-g") {
202			shift @ARGV;
203			@ARGV = map +(File::Glob::bsd_glob $_, File::Glob::GLOB_BRACE \| File::Glob::GLOB_QUOTE), @ARGV;
204			}
205	root	1.74	$schnauzer->set_paths ([@ARGV], 1, $show_first);
206	root	1.71	}
207	root	1.17	} else {
208	root	1.68	$schnauzer->set_dir (File::Spec->curdir, sub {
209			$mainwin->show_all;
210			$viewer->show_all;
211			});
212	root	1.12	}
213
214			main Gtk2;
215	root	1.21
216	root	1.69	Gtk2::CV::flush_aio;
217
218	root	1.21	__DATA__
219	root	1.12
220	root	1.58	=encoding utf-8
221
222	root	1.11	=head1 NAME
223
224	root	1.47	cv - a fast gtk+ image viewer loosely modeled after XV
225	root	1.11
226			=head1 SYNOPSIS
227
228			cv [file...]
229
230	root	1.47	=head1 FEATURES
231
232			CV is supposed to work similar to the venerable XV image viewer, just
233			faster. Why faster?
234
235			=over 4
236
237			=item * optimized directory scanning algorithm
238
239	root	1.55	The directory scanning in CV uses some tricks that - on most modern
240	root	1.47	filesystems - makes it possible to detect filetypes faster than stat()'ing
241			every file. This makes CV suitable for directories with lots of files
242			(10000+).
243
244			This algorithm is quite unprecise - it doesn't make a difference between
245			files, device nodes, symlinks and the like, and filetype detection is done
246			using the file extension only.
247
248	root	1.55	On the positive side, it is usually many orders of magnitude faster than
249			traditional scanning techniques (good for directories with 10000 or
250			100000+ files).
251
252	root	1.53	=item * queuing for all time-consuming background tasks
253
254			All tasks, such as unlinking files or generating thumbnails, that can be
255			done in the background will be done so - no waiting required, even when
256			changing directories.
257
258	root	1.47	=item * use of asynchronous I/O
259
260			CV tries to use asynchronous I/O whereever it makes sense, for example
261	root	1.53	while scanning directories, waiting for stat data, unlinking files or
262			generating thumbnails. This usually decreases scanning times for large
263			directories a bit (especially on RAID devices and over NFS) and makes CV
264			much more interactive.
265	root	1.47
266			=item * fast image loading
267
268			The time span between the user issuing a command and displaying the new
269			image should be as small as possible. CV uses optimized (especially
270			for JPEG) loading functions and sacrifices some quality (e.g no gamma
271	root	1.55	correction, although this might change) to achieve this speed.
272	root	1.47
273			=item * fast thumbnail creation
274
275	root	1.55	Thumbnail creation uses both CPU and Disk-I/O. CV interleaves both, so
276			on modern CPUs, thumbnailing is usually limited by I/O speed. Thumbnail
277			creation for JPEGs has been specially optimized and can even take
278			advantage of multiple CPUs.
279	root	1.47
280			=item * minimum optical clutter
281
282			CV has no menus or other user interface elements that take up a lot of
283	root	1.55	screen space (or are useful for beginning users). The schnauzer windows
284			can also be somewhat crowded.
285	root	1.47
286			The point of an image viewer is viewing images, not a nice GUI. This is
287			similar to XV's behaviour.
288
289			=item * efficient (and hard to learn) user interface
290
291			CV uses key combinations. A lot. If you are an experienced XV user, you
292			will find most of these keys familiar. If not, CV might be hard to use at
293			first, but will be an efficient tool later.
294
295	root	1.55	=item * multi-window GUI
296
297			CV doesn't force you to use a specific layout, instead it relies on your
298			window manager, thus enabling you to chose whatever layout that suits you
299			most.
300
301	root	1.47	=item * i18n'ed filename handling throughout
302
303			As long as glib can recognize your filename encoding (either UTF-8 or
304	root	1.55	locale-specific, depending on the setting of G_BROKEN_FILENAMES) and you
305			have the relevant fonts, CV will display your filenames correctly.
306	root	1.47
307			=item * extensible through plug-ins
308
309			I have weird plug-ins that access remote databases to find a
310			directory. This is not likely to be of any use to other people. Likewise,
311			others might have weird requirements I cannot dream of.
312
313			=item * filename clustering
314
315			Among the standard plug-ins is a filename clustering plug-in, that (in
316			case of tens of thousands images in one directory) might be able to
317			cluster similar names together.
318
319			=back
320
321	root	1.11	=head1 DESCRIPTION
322
323			=head2 THE IMAGE WINDOW
324
325			You can use the following keys in the image window:
326
327	root	1.50	q quit the program
328			< half the image size
329			> double the image size
330			, shrink the image by 10%
331			. enlarge the image by 10%
332			n reset to normal size
333			m maximize to screensize
334			M maximize to screensize, respecting image aspect
335			ctrl-m toggle maxpect-always mode
336	root	1.59	ctrl-sift-m toggle using current image size as max image size
337	root	1.50	u uncrop
338			r set scaling mode to 'nearest' (fastest)
339			s set scaling mode to 'bilinear' (default)
340			shift-s set scaling mode to 'hyper' (slowest)
341			t rotate clockwise 90°
342			T rotate counterclockwise°
343	root	1.64	a apply all rotations loslessly to a jpeg file (using exiftran)
344	root	1.50	ctrl-v open a new visual schnauzer window for the current dir
345	root	1.63	ctrl-c clone the current image window
346	root	1.50	ctrl-e run an editor ($CV_EDITOR or "gimp") on the current image
347	root	1.57	ctrl-p fire up the print dialog
348	root	1.50	escape cancel a crop action
349	root	1.11
350	root	1.33	And when playing movies, these additional keys are active:
351
352	root	1.50	left rewind by 10 seconds
353			right forward by 10 seconds
354			down rewind by 60 seconds
355			up forward by 60 seconds
356			pg_up rewind by 600 seconds
357			pg_down forward by 600 seconds
358			o toggle on-screen display
359			p pause/unpause
360			escape stop playing
361			9 turn volume down
362			0 turn volume up
363	root	1.33
364	root	1.47	Any other keys will be sent to the default schnauzer window, which can be
365			toggled on and off by right-clicking into the image window.
366	root	1.11
367	root	1.47	Left-clicking into the image window will let you crop the image (usually
368			to zoom into large images that CV scales down).
369	root	1.11
370			=head2 THE VISUAL SCHNAUZER
371
372	root	1.63	Any image-loading action in a schnauzer window acts on the
373			"last-recently-activated" imagewindow, which currently is simply the last
374			image window that received a keypress.
375
376	root	1.11	You can use the following keys in the schnauzer window:
377
378	root	1.47	ctrl-space,
379	root	1.50	space move to and display next image
380	root	1.47	ctrl-backspace,
381	root	1.50	backspace move to and display previous image
382	root	1.47	ctrl-return,
383	root	1.50	return display selected picture, or enter directory
384	root	1.11
385	root	1.50	cursor keys move selection
386			page-up move one page up
387			page-down move one page down
388			home move to first file
389			end move to last file
390
391			ctrl-a select all files
392			ctrl-shift-a select all files currently displayed in the schnauzer window
393			ctrl-d delete selected files WITHOUT ASKING AGAIN
394			ctrl-g force generation of thumbnais for the selected files
395			ctrl-s rescan current direcory or files updates/deletes etc.
396			ctrl-u update selected (or all) icons if neccessary
397	root	1.76	ctrl-- unselected thumbnailed images
398			ctrl-+ keep only thumbnailed images, deselect others
399	root	1.47
400	root	1.56	^ go to parent directory (caret).
401
402	root	1.47	0-9,
403	root	1.50	a-z find the first filename beginning with this letter
404	root	1.47
405			Right-clicking into the schnauzer window displays a pop-up menu with
406			additional actions.
407
408	root	1.60	=head3 SELECTION
409
410			You can select entries in the Schnauzer in a variety of ways:
411
412			=over 4
413
414			=item Keyboard
415
416			Moving the cursor with the keyboard will first deselect all files and then
417			select the file you moved to.
418
419	root	1.61	=item Clicking
420	root	1.60
421	root	1.61	Clicking on an entry will select the one you clicked and deselect all
422			others.
423	root	1.60
424	root	1.61	=item Shift-Clicking
425
426			Shift-clicking will toggle the selection on the entry under the mouse.
427
428			=item Dragging
429	root	1.60
430			Dragging will select all entries between the one selected when pushing the
431			button and the one selected when releasing the button. If you move above
432			or below the schnauzer area while drag-selecting, the schnauzer will move
433			up/down one row twice per second. In addition, horizontal mouse movement
434			acts as a kind of invisible horizontal scrollbar.
435
436			=item Hint: double-click works while click-selecting
437
438			You can double-click any image while click-selecting to display it
439			without stopping the selection process. This will act as if you normally
440			double-clicked the image to display it, and will toggle the selection
441			twice, resulting in no change.
442
443			=back
444
445	root	1.47	=head1 FILES
446
447			When starting, CV runs the F<.cvrc> file in your F<$HOME> directory as if
448			it were a perl script. in that, you will mostly load plug-ins.
449
450			Example:
451
452			system "fping -q -t 10 ether"
453			or require "/fs/cv/cvplugin.pl";
454
455			This will load a plug-in, but only if the machine I<ether> is reachable
456			(supposedly the plug-in is networked in some way :).
457	root	1.11
458	root	1.79	=head1 ENVIRONMENT VARIABLES
459	root	1.27
460			=over 4
461
462	root	1.38	=item CV_EDITOR
463
464			The program that gets executed when the user presses C<CTRL-e> in the
465			Schnauzer or image window. The default is C<gimp>.
466
467	root	1.70	=item CV_AUDIO_PLAYER
468
469			Program used to play all sorts of audio (wav, aif, mp3, ogg...), default "play".
470			Will be called like C<< $CV_AUDIO_PLAYER -- <path> >>.
471
472	root	1.27	=item CV_PRINT_DESTINATION
473
474			The default (perl-style) destination to use in the print dialog.
475
476	root	1.38	=item CV_TRASHCAN
477
478	root	1.78	When set, must point to a directory where all files that are deleted by
479			the "Delete Physically" (ctrl-d) action are moved to (other deletion
480			actions still delete!). If unset, files that are deleted are really being
481			deleted.
482	root	1.38
483	root	1.27	=back
484
485	root	1.79	=head1 SIGNALS
486
487			Sending CV a SIGUSR1 signal will cause all image viewers to reload the
488			currently loaded image. This is useful if you use CV as a viewer for
489			changing data - just run it in the background with some path and each time
490			the image changes, send it a SIGUSR1.
491
492	root	1.23	=head1 SECURITY CONSIDERATIONS
493
494	root	1.54	CV uses Pixbuf to load non-JPEG images. Pixbuf is not considered safe for
495			this purpose, though (from the gtk-2.2 release notes):
496	root	1.23
497			"While efforts have been made to make gdk-pixbuf robust against invalid
498			images, using gdk-pixbuf to load untrusted data is not recommended, due to
499			the likelyhood that there are additional problems where an invalid image
500			could cause gdk-pixbuf to crash or worse."
501
502	root	1.11	=head1 BUGS/TODO
503	root	1.23
504	root	1.47	Lots of functionality is missing.
505
506			Pixbuf doesn't always honor G_BROKEN_FILENAMES, so accessing files with
507	root	1.54	names incompatible with utf-8 might fail.
508	root	1.11
509			rotate on disk
510			lots of ui issues
511			save(?)
512			preferences
513
514			=head1 AUTHOR
515
516			Marc Lehmann <cv@plan9.de>.
517
518			=cut
519	root	1.1