source: main/trunk/greenstone2/perllib/plugins/PDFPlugin.pm@ 22874

Last change on this file since 22874 was 22874, checked in by kjdon, 14 years ago

no longer use filename_extension, as we should be using the original extension . eg when processing an odt doc with word plugin, the associated file used to be doc.doc, instead of doc.odt.
  • Property svn:keywords set to Author Date Id Revision
File size: 13.0 KB
Line 
1###########################################################################
2#
3# PDFPlugin.pm -- reasonably with-it pdf plugin
4# A component of the Greenstone digital library software
5# from the New Zealand Digital Library Project at the
6# University of Waikato, New Zealand.
7#
8# Copyright (C) 1999-2001 New Zealand Digital Library Project
9#
10# This program is free software; you can redistribute it and/or modify
11# it under the terms of the GNU General Public License as published by
12# the Free Software Foundation; either version 2 of the License, or
13# (at your option) any later version.
14#
15# This program is distributed in the hope that it will be useful,
16# but WITHOUT ANY WARRANTY; without even the implied warranty of
17# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18# GNU General Public License for more details.
19#
20# You should have received a copy of the GNU General Public License
21# along with this program; if not, write to the Free Software
22# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23#
24###########################################################################
25package PDFPlugin;
26
27use strict;
28no strict 'refs'; # so we can use a var for filehandles (e.g. STDERR)
29
30use ReadTextFile;
31use unicode;
32
33use AutoLoadConverters;
34use ConvertBinaryFile;
35
36@PDFPlugin::ISA = ('ConvertBinaryFile', 'AutoLoadConverters', 'ReadTextFile');
37
38
39my $convert_to_list =
40 [ { 'name' => "auto",
41 'desc' => "{ConvertBinaryFile.convert_to.auto}" },
42 { 'name' => "html",
43 'desc' => "{ConvertBinaryFile.convert_to.html}" },
44 { 'name' => "text",
45 'desc' => "{ConvertBinaryFile.convert_to.text}" },
46 { 'name' => "pagedimg_jpg",
47 'desc' => "{ConvertBinaryFile.convert_to.pagedimg_jpg}"},
48 { 'name' => "pagedimg_gif",
49 'desc' => "{ConvertBinaryFile.convert_to.pagedimg_gif}"},
50 { 'name' => "pagedimg_png",
51 'desc' => "{ConvertBinaryFile.convert_to.pagedimg_png}"},
52 ];
53
54
55my $arguments =
56 [
57 { 'name' => "convert_to",
58 'desc' => "{ConvertBinaryFile.convert_to}",
59 'type' => "enum",
60 'reqd' => "yes",
61 'list' => $convert_to_list,
62 'deft' => "html" },
63 { 'name' => "process_exp",
64 'desc' => "{BasePlugin.process_exp}",
65 'type' => "regexp",
66 'deft' => &get_default_process_exp(),
67 'reqd' => "no" },
68 { 'name' => "block_exp",
69 'desc' => "{BasePlugin.block_exp}",
70 'type' => "regexp",
71 'deft' => &get_default_block_exp() },
72 { 'name' => "metadata_fields",
73 'desc' => "{HTMLPlugin.metadata_fields}",
74 'type' => "string",
75 'deft' => "" },
76 { 'name' => "metadata_field_separator",
77 'desc' => "{HTMLPlugin.metadata_field_separator}",
78 'type' => "string",
79 'deft' => "" },
80 { 'name' => "noimages",
81 'desc' => "{PDFPlugin.noimages}",
82 'type' => "flag" },
83 { 'name' => "allowimagesonly",
84 'desc' => "{PDFPlugin.allowimagesonly}",
85 'type' => "flag" },
86 { 'name' => "complex",
87 'desc' => "{PDFPlugin.complex}",
88 'type' => "flag" },
89 { 'name' => "nohidden",
90 'desc' => "{PDFPlugin.nohidden}",
91 'type' => "flag" },
92 { 'name' => "zoom",
93 'desc' => "{PDFPlugin.zoom}",
94 'deft' => "2",
95 'range' => "1,3", # actually the range is 0.5-3
96 'type' => "int" },
97 { 'name' => "use_sections",
98 'desc' => "{PDFPlugin.use_sections}",
99 'type' => "flag" },
100 { 'name' => "description_tags",
101 'desc' => "{HTMLPlugin.description_tags}",
102 'type' => "flag" }
103 ];
104
105my $options = { 'name' => "PDFPlugin",
106 'desc' => "{PDFPlugin.desc}",
107 'abstract' => "no",
108 'inherits' => "yes",
109 'srcreplaceable' => "yes", # Source docs in PDF can be replaced with GS-generated html
110 'args' => $arguments };
111
112sub new {
113 my ($class) = shift (@_);
114 my ($pluginlist,$inputargs,$hashArgOptLists) = @_;
115 push(@$pluginlist, $class);
116
117 push(@$inputargs,"-title_sub");
118 push(@$inputargs,'^(Page\s+\d+)?(\s*1\s+)?');
119
120 push(@{$hashArgOptLists->{"ArgList"}},@{$arguments});
121 push(@{$hashArgOptLists->{"OptList"}},$options);
122
123 my $auto_converter_self = new AutoLoadConverters($pluginlist,$inputargs,$hashArgOptLists,["PDFBoxConverter"],1);
124 my $cbf_self = new ConvertBinaryFile($pluginlist, $inputargs, $hashArgOptLists);
125 my $self = BasePlugin::merge_inheritance($auto_converter_self, $cbf_self);
126
127 if ($self->{'info_only'}) {
128 # don't worry about any options etc
129 return bless $self, $class;
130 }
131
132 $self = bless $self, $class;
133 $self->{'file_type'} = "PDF";
134
135 # these are passed through to gsConvert.pl by ConvertBinaryFile.pm
136 my $zoom = $self->{"zoom"};
137 $self->{'convert_options'} = "-pdf_zoom $zoom";
138 $self->{'convert_options'} .= " -pdf_complex" if $self->{"complex"};
139 $self->{'convert_options'} .= " -pdf_nohidden" if $self->{"nohidden"};
140 $self->{'convert_options'} .= " -pdf_ignore_images" if $self->{"noimages"};
141 $self->{'convert_options'} .= " -pdf_allow_images_only" if $self->{"allowimagesonly"};
142
143 # check convert_to
144 if ($self->{'convert_to'} eq "text" && $ENV{'GSDLOS'} =~ /^windows$/i) {
145 print STDERR "Windows does not support pdf to text. PDFs will be converted to HTML instead\n";
146 $self->{'convert_to'} = "html";
147 }
148 elsif ($self->{'convert_to'} eq "auto") {
149 # choose html ?? is this the best option
150 $self->{'convert_to'} = "html";
151 }
152 # set convert_to_plugin and convert_to_ext
153 $self->set_standard_convert_settings();
154
155 my $secondary_plugin_name = $self->{'convert_to_plugin'};
156 my $secondary_plugin_options = $self->{'secondary_plugin_options'};
157
158 if (!defined $secondary_plugin_options->{$secondary_plugin_name}) {
159 $secondary_plugin_options->{$secondary_plugin_name} = [];
160 }
161 my $specific_options = $secondary_plugin_options->{$secondary_plugin_name};
162
163 # following title_sub removes "Page 1" added by pdftohtml, and a leading
164 # "1", which is often the page number at the top of the page. Bad Luck
165 # if your document title actually starts with "1 " - is there a better way?
166 push(@$specific_options , "-title_sub", '^(Page\s+\d+)?(\s*1\s+)?');
167 my $associate_tail_re = $self->{'associate_tail_re'};
168 if ((defined $associate_tail_re) && ($associate_tail_re ne "")) {
169 push(@$specific_options, "-associate_tail_re", $associate_tail_re);
170 }
171 push(@$specific_options, "-file_rename_method", "none");
172
173 if ($secondary_plugin_name eq "HTMLPlugin") {
174 # pdftohtml always produces utf8 - What about pdfbox???
175 push(@$specific_options, "-input_encoding", "utf8");
176 push(@$specific_options, "-extract_language") if $self->{'extract_language'};
177 push(@$specific_options, "-processing_tmp_files");
178 # Instruct HTMLPlug (when eventually accessed through read_into_doc_obj)
179 # to extract these metadata fields from the HEAD META fields
180 if (defined $self->{'metadata_fields'} && $self->{'metadata_fields'} =~ /\S/) {
181 push(@$specific_options,"-metadata_fields",$self->{'metadata_fields'});
182 } else {
183 push(@$specific_options,"-metadata_fields","Title,GENERATOR,date,author<Creator>");
184 }
185 if (defined $self->{'metadata_field_separator'} && $self->{'metadata_field_separator'} =~ /\S/) {
186 push(@$specific_options,"-metadata_field_separator",$self->{'metadata_field_separator'});
187 }
188 if ($self->{'use_sections'} || $self->{'description_tags'}) {
189 $self->{'description_tags'} = 1;
190 push(@$specific_options, "-description_tags");
191 }
192 }
193 elsif ($secondary_plugin_name eq "PagedImagePlugin") {
194 push(@$specific_options, "-screenviewsize", "1000");
195 push(@$specific_options, "-enable_cache");
196 push(@$specific_options, "-processing_tmp_files");
197 }
198
199 $self = bless $self, $class;
200 $self->load_secondary_plugins($class,$secondary_plugin_options,$hashArgOptLists);
201 return $self;
202}
203
204sub get_default_process_exp {
205 my $self = shift (@_);
206
207 return q^(?i)\.pdf$^;
208}
209
210# so we don't inherit HTMLPlug's block exp...
211sub get_default_block_exp {
212 return "";
213}
214
215sub init {
216 my $self = shift (@_);
217
218 # ConvertBinaryFile init
219 $self->SUPER::init(@_);
220 $self->AutoLoadConverters::init();
221
222}
223
224sub begin {
225 my $self = shift (@_);
226
227 $self->AutoLoadConverters::begin();
228 $self->SUPER::begin(@_);
229
230}
231
232sub deinit {
233 my $self = shift (@_);
234
235 $self->AutoLoadConverters::deinit();
236 $self->SUPER::deinit(@_);
237
238}
239
240
241sub tmp_area_convert_file {
242
243 my $self = shift (@_);
244 return $self->AutoLoadConverters::tmp_area_convert_file(@_);
245
246}
247
248sub convert_post_process
249{
250 my $self = shift (@_);
251 my ($conv_filename) = @_;
252
253 my $outhandle=$self->{'outhandle'};
254
255 #$self->{'input_encoding'} = "utf8"; # The output is always in utf8 (is it?? it is for html, but what about other types?)
256 #my ($language, $encoding) = $self->textcat_get_language_encoding ($conv_filename);
257
258 # read in file ($text will be in utf8)
259 my $text = "";
260 # encoding will be utf8 for html files - what about other types? will we do this step for them anyway?
261 $self->read_file ($conv_filename, "utf8", "", \$text);
262
263 # Calculate number of pages based on <a ...> tags (we have a <a name=1> etc
264 # for each page). Metadata based on this calculation not set until process()
265 #
266 # Note: this is done even if we are not breaking to document into pages as it might
267 # be useful to give an indication of document length in browser through setting
268 # num_pages as metadata.
269 my @pages = ($text =~ /\<[Aa] name=\"?\w+\"?>/ig);
270 my $num_pages = scalar(@pages);
271 $self->{'num_pages'} = $num_pages;
272
273 if ($self->{'use_sections'}
274 && $self->{'converted_to'} eq "HTML") {
275
276 print $outhandle "PDFPlugin: Calculating sections...\n";
277
278 # we have "<a name=1></a>" etc for each page
279 # it may be <A name=
280 my @sections = split('<[Aa] name=', $text);
281
282 my $top_section = "";
283
284 if (scalar (@sections) == 1) { #only one section - no split!
285 print $outhandle "PDFPlugin: warning - no sections found\n";
286 } else {
287 $top_section .= shift @sections; # keep HTML header etc as top_section
288 }
289
290 # handle first section specially for title? Or all use first 100...
291
292 my $title = $sections[0];
293 $title =~ s/^\"?\w+\"?>//; # specific for pdftohtml...
294 $title =~ s/<\/([^>]+)><\1>//g; # (eg) </b><b> - no space
295 $title =~ s/<[^>]*>/ /g;
296 $title =~ s/(?:&nbsp;|\xc2\xa0)/ /g; # utf-8 for nbsp...
297 $title =~ s/^\s+//s;
298 $title =~ s/\s+$//;
299 $title =~ s/\s+/ /gs;
300 $title =~ s/^$self->{'title_sub'}// if ($self->{'title_sub'});
301 $title =~ s/^\s+//s; # in case title_sub introduced any...
302 $title = substr ($title, 0, 100);
303 $title =~ s/\s\S*$/.../;
304
305
306 if (scalar (@sections) == 1) { # no sections found
307 $top_section .= $sections[0];
308 @sections=();
309 } else {
310 $top_section .= "<!--<Section>\n<Metadata name=\"Title\">$title</Metadata>\n-->\n <!--</Section>-->\n";
311 }
312
313 # add metadata per section...
314 foreach my $section (@sections) {
315 # section names are not always just digits, may be like "outline"
316 $section =~ s@^\"?(\w+)\"?></a>@@; # leftover from split expression...
317
318 $title = $1; # Greenstone does magic if sections are titled digits
319 if (! defined($title) ) {
320 print STDERR "no title: $section\n";
321 $title = " "; # get rid of the undefined warning in next line
322 }
323 my $newsection = "<!-- from PDFPlugin -->\n<!-- <Section>\n";
324 $newsection .= "<Metadata name=\"Title\">" . $title
325 . "</Metadata>\n--><p>\n";
326 $newsection .= $section;
327 $newsection .= "<!--</Section>-->\n";
328 $section = $newsection;
329 }
330
331 $text=join('', ($top_section, @sections));
332 }
333
334 # turn any high bytes that aren't valid utf-8 into utf-8.
335 unicode::ensure_utf8(\$text);
336
337 # Write it out again!
338 $self->utf8_write_file (\$text, $conv_filename);
339}
340
341
342# do plugin specific processing of doc_obj for HTML type
343sub process {
344 my $self = shift (@_);
345 my ($pluginfo, $base_dir, $file, $metadata, $doc_obj, $gli) = @_;
346
347 my $result = $self->process_type($base_dir,$file,$doc_obj);
348
349 # fix up the extracted date metadata to be in Greenstone date format,
350 # and fix the capitalisation of 'date'
351 my $cursection = $doc_obj->get_top_section();
352 foreach my $datemeta (@{$doc_obj->get_metadata($cursection, "date")}) {
353 $doc_obj->delete_metadata($cursection, "date", $datemeta);
354
355 # We're just interested in the date bit, not the time
356 # some pdf creators (eg "Acrobat 5.0 Scan Plug-in for Windows")
357 # set a /CreationDate, and set /ModDate to 000000000. pdftohtml
358 # extracts the ModDate, so it is 0...
359 $datemeta =~ /(\d+)-(\d+)-(\d+)/;
360 my ($year, $month, $day) = ($1,$2,$3);
361 if (defined($year) && defined($month) && defined($day)) {
362 if ($year == 0) {next}
363 if ($year < 100) {$year += 1900} # just to be safe
364 if ($month =~ /^\d$/) {$month="0$month"} # single digit
365 if ($day =~ /^\d$/) {$day="0$day"} # single digit
366 my $date="$year$month$day";
367 $doc_obj->add_utf8_metadata($cursection, "Date", $date);
368 }
369 }
370
371 $doc_obj->add_utf8_metadata($cursection, "NumPages", $self->{'num_pages'});
372
373 if ($self->{'use_sections'} && $self->{'converted_to'} eq "HTML") {
374 # we explicitly make it a paged document, cos greenstone won't get it
375 # right if any section has an empty title, or one with letters in it
376 $doc_obj->set_utf8_metadata_element ($cursection, "gsdlthistype", "Paged");
377 }
378
379 return $result;
380}
381
3821;
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