source: main/trunk/greenstone2/perllib/plugins/ImagePlugin.pm@ 36271

Last change on this file since 36271 was 36271, checked in by davidb, 20 months ago

Check for any sign of text being bound to the doc, before going ahead with the 'dummy text' hack originally added in for mg

  • Property svn:keywords set to Author Date Id Revision
File size: 5.4 KB
Line 
1###########################################################################
2#
3# ImagePlugin.pm -- for processing standalone images
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 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###########################################################################
25
26package ImagePlugin;
27
28use BaseImporter;
29use ImageConverter;
30
31use strict;
32no strict 'refs'; # allow filehandles to be variables and viceversa
33no strict 'subs';
34
35use gsprintf 'gsprintf';
36
37sub BEGIN {
38 @ImagePlugin::ISA = ('BaseImporter', 'ImageConverter');
39}
40
41my $arguments =
42 [ { 'name' => "process_exp",
43 'desc' => "{BaseImporter.process_exp}",
44 'type' => "regexp",
45 'deft' => &get_default_process_exp(),
46 'reqd' => "no" },
47 ];
48
49my $options = { 'name' => "ImagePlugin",
50 'desc' => "{ImagePlugin.desc}",
51 'abstract' => "no",
52 'inherits' => "yes",
53 'args' => $arguments };
54
55
56
57sub new {
58 my ($class) = shift (@_);
59 my ($pluginlist,$inputargs,$hashArgOptLists) = @_;
60 push(@$pluginlist, $class);
61
62 push(@{$hashArgOptLists->{"ArgList"}},@{$arguments});
63 push(@{$hashArgOptLists->{"OptList"}},$options);
64
65
66 new ImageConverter($pluginlist, $inputargs, $hashArgOptLists);
67 my $self = new BaseImporter($pluginlist, $inputargs, $hashArgOptLists);
68
69 return bless $self, $class;
70}
71
72sub init {
73 my $self = shift (@_);
74 my ($verbosity, $outhandle, $failhandle) = @_;
75
76 $self->SUPER::init(@_);
77 $self->ImageConverter::init();
78 $self->{'cover_image'} = 0; # makes no sense for images
79}
80
81sub begin {
82 my $self = shift (@_);
83 my ($pluginfo, $base_dir, $processor, $maxdocs) = @_;
84
85 $self->SUPER::begin(@_);
86 $self->ImageConverter::begin(@_);
87}
88
89
90sub get_default_process_exp {
91 my $self = shift (@_);
92
93 # from .jpf and onwards below, the file extensions are for JPEG2000
94 return q^(?i)\.(jpe?g|gif|png|bmp|xbm|tif?f|jpf|jpx|jp2|jpc|j2k|pnm|pgx)$^;
95}
96
97# this makes no sense for images
98sub block_cover_image
99{
100 my $self =shift (@_);
101 my ($filename) = @_;
102
103 return;
104}
105
106# do plugin specific processing of doc_obj
107sub process {
108 my $self = shift (@_);
109 # options??
110 my ($pluginfo, $base_dir, $file, $metadata, $doc_obj, $gli) = @_;
111
112 my $outhandle = $self->{'outhandle'};
113 my ($filename_full_path, $filename_no_path) = &util::get_full_filenames($base_dir, $file);
114
115 if ($self->{'image_conversion_available'} == 1)
116 {
117 my $plugin_filename_encoding = $self->{'filename_encoding'};
118 my $filename_encoding = $self->deduce_filename_encoding($file,$metadata,$plugin_filename_encoding);
119
120 my $url_encoded_full_filename
121 = &unicode::raw_filename_to_url_encoded($filename_full_path);
122
123 # should we check the return value?
124 $self->generate_images($filename_full_path,
125 $url_encoded_full_filename,
126 $doc_obj, $doc_obj->get_top_section(),$filename_encoding);
127
128 }
129 else
130 {
131 if ($gli) {
132 &gsprintf(STDERR, "<Warning p='ImagePlugin' r='{ImageConverter.noconversionavailable}: {ImageConverter.".$self->{'no_image_conversion_reason'}."}'>");
133 }
134 # all we do is add the original image as an associated file, and set up srclink etc
135 my $assoc_file = $doc_obj->get_assocfile_from_sourcefile();
136 my $section = $doc_obj->get_top_section();
137
138 $doc_obj->associate_file($filename_full_path, $assoc_file, "", $section);
139
140 # srclink_file is now deprecated because of the "_" in the metadataname. Use srclinkFile
141 $doc_obj->add_metadata ($section, "srclink_file", $doc_obj->get_sourcefile());
142 $doc_obj->add_metadata ($section, "srclinkFile", $doc_obj->get_sourcefile());
143 # We don't know the size of the image, but the browser should display it at full size
144 $doc_obj->add_metadata ($section, "srcicon", "<img src=\"_httpprefix_/collect/[collection]/index/assoc/[assocfilepath]/[srclinkFile]\">");
145
146 # Add a fake thumbnail icon with the full-sized image scaled down by the browser
147 $doc_obj->add_metadata ($section, "thumbicon", "<img src=\"_httpprefix_/collect/[collection]/index/assoc/[assocfilepath]/[srclinkFile]\" alt=\"[srclinkFile]\" width=\"" . $self->{'thumbnailsize'} . "\">");
148 }
149
150 # A plugin inheriting from this might be able to derive text from the image
151 # (e.g., through GoogleVisionAPI), and so don't just assume there is no
152 # text for the image -- check it's text length, and only set the dummy
153 # text if it is zero
154 if ($doc_obj->get_total_text_length() == 0) {
155 #we have no text - adds dummy text and NoText metadata
156 $self->add_dummy_text($doc_obj, $doc_obj->get_top_section());
157 }
158
159 return 1;
160
161}
162
163
164sub clean_up_after_doc_obj_processing {
165 my $self = shift(@_);
166
167 $self->ImageConverter::clean_up_temporary_files();
168}
169
1701;
171
172
173
174
175
176
177
178
179
180
181
Note: See TracBrowser for help on using the repository browser.