root/main/trunk/greenstone2/perllib/plugins/EmbeddedMetadataPlugin.pm @ 24404

Revision 24404, 8.8 KB (checked in by ak19, 8 years ago)

Changes to perl code to do with removing the ex. prefix: ex. is only removed if it is the sole prefix (i.e. ex.dc.* prefixes are not removed).

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1###########################################################################
2#
3# EmbeddedMetadataPlugin.pm -- A plugin for EXIF
4#
5# A component of the Greenstone digital library software
6# from the New Zealand Digital Library Project at the
7# University of Waikato, New Zealand.
8#
9# Copyright 2007 New Zealand Digital Library Project
10#
11# This program is free software; you can redistribute it and/or modify
12# it under the terms of the GNU General Public License as published by
13# the Free Software Foundation; either version 2 of the License, or
14# (at your option) any later version.
15#
16# This program is distributed in the hope that it will be useful,
17# but WITHOUT ANY WARRANTY; without even the implied warranty of
18# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19# GNU General Public License for more details.
20#
21# You should have received a copy of the GNU General Public License
22# along with this program; if not, write to the Free Software
23# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24#
25###########################################################################
26
27
28package EmbeddedMetadataPlugin;
29
30use BasePlugin;
31
32use Encode;
33use Image::ExifTool qw(:Public);
34use strict;
35
36no strict 'refs'; # allow filehandles to be variables and viceversa
37
38
39sub BEGIN
40{
41    @EmbeddedMetadataPlugin::ISA = ('BasePlugin');
42    binmode(STDERR, ":utf8");
43}
44
45my $encoding_plus_auto_list = [{
46        'name' => "auto",
47        'desc' => "{ReadTextFile.input_encoding.auto}" }];
48push(@{$encoding_plus_auto_list},@{$BasePlugin::encoding_list});
49
50my $arguments = [{
51    'name' => "metadata_field_separator",
52    'desc' => "{HTMLPlugin.metadata_field_separator}",
53    'type' => "string",
54    'deft' => ""
55    },{
56    'name' => "input_encoding",
57    'desc' => "{ReadTextFile.input_encoding}",
58    'type' => "enum",
59    'list' => $encoding_plus_auto_list,
60    'reqd' => "no",
61    'deft' => "auto"
62    },{
63    'name' => "join_before_split",
64    'desc' => "{EmbeddedMetadataPlugin.join_before_split}",
65    'type' => "flag"
66    },{
67    'name' => "join_character",
68    'desc' => "{EmbeddedMetadataPlugin.join_character}",
69    'type' => "string",
70    'deft' => " "
71    },{
72    'name' => "trim_whitespace",
73    'desc' => "{EmbeddedMetadataPlugin.trim_whitespace}",
74    'type' => "enum",
75    'list' => [{'name' => "true", 'desc' => "{common.true}"}, {'name' => "false", 'desc' => "{common.false}"}],
76    'deft' => "true"
77    }];
78
79my $options = {
80    'name'     => "EmbeddedMetadataPlugin",
81    'desc'     => "{EmbeddedMetadataPlugin.desc}",
82    'abstract' => "no",
83    'inherits' => "yes",
84    'args'     => $arguments };
85
86sub new()
87{
88    my ($class) = shift (@_);
89    my ($pluginlist,$inputargs,$hashArgOptLists) = @_;
90    push(@$pluginlist, $class);
91
92    if(defined $arguments){ push(@{$hashArgOptLists->{"ArgList"}},@{$arguments});}
93    if(defined $options) { push(@{$hashArgOptLists->{"OptList"}},$options)};
94
95    my $self = new BasePlugin($pluginlist, $inputargs, $hashArgOptLists);
96
97    # Create a new Image::ExifTool object
98    my $exifTool = new Image::ExifTool;
99    $exifTool->Options(Duplicates => 0);
100    $exifTool->Options(PrintConv => 0);
101    $exifTool->Options(Unknown => 1);
102    $exifTool->Options('Verbose');
103    $self->{'exiftool'} = $exifTool;
104
105    return bless $self, $class;
106}
107
108
109# Need to think some more about this
110sub get_default_process_exp()
111{
112    return ".*";
113    #q^(?i)\.(wma|wmv|jpe?g|gif)$^;
114}
115
116
117# This plugin doesn't block any files
118#sub get_default_block_exp()
119#{
120#    return '';
121#}
122
123# plugins that rely on more than process_exp (eg XML plugins) can override this method
124sub can_process_this_file {
125    my $self = shift(@_);
126
127    # we process metadata, not the file
128    return 0;   
129}
130
131# Even if a plugin can extract metadata in its metadata_read pass,
132# make the default return 'undef' so processing of the file continues
133# down the pipeline, so other plugins can also have the opportunity to
134# locate metadata and set it up in the extrametakeys variables that
135# are passed around.
136
137sub can_process_this_file_for_metadata {
138    my $self = shift(@_);
139
140    # this plugin will look for metadata in any file through its
141    # metadata_read() returning undef here means anything else further
142    # down the pipeline can do the same
143
144    return undef;
145}
146
147
148sub extractEmbeddedMetadata()
149{
150    my $self = shift(@_);
151    my ($file, $filename, $extrametadata, $extrametakeys) = @_;
152 
153    my %exif_metadata = ();
154
155    my $verbosity = $self->{'verbosity'};
156    my $outhandle = $self->{'outhandle'};
157
158    my $metadata_count = 0;
159   
160    my $separator = $self->{'metadata_field_separator'};
161    if ($separator eq "") {
162        undef $separator;
163    }
164
165    my @group_list = Image::ExifTool::GetAllGroups(0);
166    foreach my $group (@group_list) {
167##  print STDERR "**** group = $group\n";
168
169        # Extract meta information from an image
170        $self->{'exiftool'}->Options(Group0 => [$group]);
171        $self->{'exiftool'}->ExtractInfo($filename);
172
173        # Get list of tags in the order they were found in the file
174        my @tag_list = $self->{'exiftool'}->GetFoundTags('File');
175        foreach my $tag (@tag_list) {
176
177            # Strip any numbering suffix
178            $tag =~ s/^([^\s]+)\s.*$/$1/i;
179            my $value = $self->{'exiftool'}->GetValue($tag);
180            if (defined $value && $value =~ /[a-z0-9]+/i) {
181                my $field = "ex.$group.$tag";
182       
183                my $encoding = $self->{'input_encoding'};
184                if($encoding eq "auto")
185                {
186                    $encoding = "utf8"
187                }
188
189                if (!defined $exif_metadata{$field})
190                {
191                    $exif_metadata{$field} = [];
192                }
193
194                $field = Encode::decode($encoding,$field);
195                my $metadata_done = 0;
196                if (ref $value eq 'SCALAR') {
197                    if ($$value =~ /^Binary data/) {
198                        $value = "($$value)";
199                    }
200                    else {
201                        my $len = length($$value);
202                        $value = "(Binary data $len bytes)";
203                    }
204                }
205                elsif (ref $value eq 'ARRAY') {
206                    $metadata_done = 1;
207                   
208                    my $allvals = "";
209                    foreach my $v (@$value) {
210                        $v = Encode::decode($encoding,$v);
211                       
212                        if(!$self->{'join_before_split'}){
213                            if (defined $separator) {
214                                my @vs = split($separator, $v);
215                                foreach my $val (@vs) {
216                                    if ($val =~ /\S/) {
217                                        push (@{$exif_metadata{$field}}, $self->gsSafe($val));
218                                        ++$metadata_count;
219                                    }
220                                }
221                            }
222                            else
223                            {
224                                push (@{$exif_metadata{$field}}, $self->gsSafe($v));
225                                ++$metadata_count;
226                            }
227                        }
228                        else{
229                            if($allvals ne ""){
230                                $allvals = $allvals . $self->{'join_character'};
231                            }
232                            $allvals = $allvals . $v;
233                        }
234                    }
235                   
236                    if($self->{'join_before_split'}){
237                        if (defined $separator) {
238                            my @vs = split($separator, $allvals);
239                            foreach my $val (@vs) {
240                                if ($val =~ /\S/) {
241                                    push (@{$exif_metadata{$field}}, $self->gsSafe($val));
242                                    ++$metadata_count;
243                                }
244                            }
245                        }
246                        else
247                        {
248                            push (@{$exif_metadata{$field}}, $self->gsSafe($allvals));
249                            ++$metadata_count;
250                        }
251                    }
252                }
253                else {
254                    $value = Encode::decode($encoding,$value);
255                    if (defined $separator) {
256                        my @vs = split($separator, $value);
257                        $metadata_done = 1;
258                        foreach my $v (@vs) {
259                            if ($v =~ /\S/) {
260                                push (@{$exif_metadata{$field}}, $self->gsSafe($v));
261                                ++$metadata_count;
262                            }
263                        }
264                    }
265                }
266                if (!$metadata_done) {
267                    push (@{$exif_metadata{$field}}, $self->gsSafe($value));
268                    ++$metadata_count;
269                }
270            }
271        }
272    }
273
274    if ($metadata_count > 0) {
275        print $outhandle " Extracted $metadata_count pieces of metadata from $filename EXIF block\n";
276    }
277
278    # Protect windows directory chars \
279    $file = &util::filename_to_regex($file);
280   
281    # Associate the metadata now
282
283    $extrametadata->{$file} = \%exif_metadata;
284    push(@$extrametakeys, $file);
285
286}
287
288
289sub metadata_read
290{
291    my $self = shift (@_);
292    my ($pluginfo, $base_dir, $file, $block_hash,
293    $extrametakeys, $extrametadata, $extrametafile,
294    $processor, $gli, $aux) = @_;
295 
296    my ($filename_full_path, $filename_no_path) = &util::get_full_filenames($base_dir, $file);
297   
298    # we don't want to process directories
299    if (!-f $filename_full_path || !$self->can_process_this_file($filename_full_path)) {
300    return undef;
301    }
302    print STDERR "\n<Processing n='$file' p='EmbeddedMetadataPlugin'>\n" if ($gli);
303    print STDERR "EmbeddedMetadataPlugin: processing $file\n" if ($self->{'verbosity'}) > 1;
304   
305    $self->extractEmbeddedMetadata($filename_no_path,$filename_full_path,
306                   $extrametadata,$extrametakeys);
307   
308    return undef;
309}
310
311sub read
312{
313    return undef;
314}
315
316sub process
317{
318    # not used
319    return undef;
320}
321
322sub gsSafe() {
323    my $self = shift(@_);
324    my ($text) = @_;
325   
326    # Replace potentially problematic characters
327    $text =~ s/\(/&#40;/g;
328    $text =~ s/\)/&#41;/g;
329    $text =~ s/,/&#44;/g;
330    $text =~ s/\</&#60;/g;
331    $text =~ s/\>/&#62;/g;
332    $text =~ s/\[/&#91;/g;
333    $text =~ s/\]/&#93;/g;
334    $text =~ s/\{/&#123;/g;
335    $text =~ s/\}/&#125;/g;
336    # Done
337   
338    if ($self->{'trim_whitespace'} eq "true"){
339        $text =~ s/^\s+//;
340        $text =~ s/\s+$//;
341    }
342   
343    return $text;
344}
345
3461;
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