Template::Plugin::Image(3pm)

1Template::Plugin::ImageU(s3e)r Contributed Perl DocumentaTteimopnlate::Plugin::Image(3)
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NAME

6       Template::Plugin::Image - Plugin access to image sizes
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SYNOPSIS

9           [% USE Image(filename) %]
10           [% Image.width %]
11           [% Image.height %]
12           [% Image.size.join(', ') %]
13           [% Image.attr %]
14           [% Image.tag %]
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DESCRIPTION

17       This plugin provides an interface to the Image::Info or Image::Size
18       modules for determining the size of image files.
19
20       You can specify the plugin name as either 'Image' or 'image'.  The
21       plugin object created will then have the same name.  The file name of
22       the image should be specified as a positional or named argument.
23
24           [% # all these are valid, take your pick %]
25           [% USE Image('foo.gif') %]
26           [% USE image('bar.gif') %]
27           [% USE Image 'ping.gif' %]
28           [% USE image(name='baz.gif') %]
29           [% USE Image name='pong.gif' %]
30
31       A "root" parameter can be used to specify the location of the image
32       file:
33
34           [% USE Image(root='/path/to/root', name='images/home.png') %]
35           # image path: /path/to/root/images/home.png
36           # img src: images/home.png
37
38       In cases where the image path and image url do not match up, specify
39       the file name directly:
40
41           [% USE Image(file='/path/to/home.png', name='/images/home.png') %]
42
43       The "alt" parameter can be used to specify an alternate name for the
44       image, for use in constructing an XHTML element (see the tag() method
45       below).
46
47           [% USE Image('home.png', alt="Home") %]
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49       You can also provide an alternate name for an Image plugin object.
50
51           [% USE img1 = image 'foo.gif' %]
52           [% USE img2 = image 'bar.gif' %]
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54       The 'name' method returns the image file name.
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56           [% img1.name %]     # foo.gif
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58       The 'width' and 'height' methods return the width and height of the
59       image, respectively.  The 'size' method returns a reference to a 2 ele‐
60       ment list containing the width and height.
61
62           [% USE image 'foo.gif' %]
63           width: [% image.width %]
64           height: [% image.height %]
65           size: [% image.size.join(', ') %]
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67       The 'modtime' method returns the ctime of the file in question, suit‐
68       able for use with date.format:
69
70           [% USE image 'foo.gif' %]
71           [% USE date %]
72           [% date.format(image.modtime, "%B, %e %Y") %]
73
74       The 'attr' method returns the height and width as HTML/XML attributes.
75
76           [% USE image 'foo.gif' %]
77           [% image.attr %]
78
79       Typical output:
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81           width="60" height="20"
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83       The 'tag' method returns a complete XHTML tag referencing the image.
84
85           [% USE image 'foo.gif' %]
86           [% image.tag %]
87
88       Typical output:
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90           <img src="foo.gif" width="60" height="20" alt="" />
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92       You can provide any additional attributes that should be added to the
93       XHTML tag.
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95           [% USE image 'foo.gif' %]
96           [% image.tag(class="logo" alt="Logo") %]
97
98       Typical output:
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100           <img src="foo.gif" width="60" height="20" alt="Logo" class="logo" />
101
102       Note that the 'alt' attribute is mandatory in a strict XHTML 'img' ele‐
103       ment (even if it's empty) so it is always added even if you don't
104       explicitly provide a value for it.  You can do so as an argument to the
105       'tag' method, as shown in the previous example, or as an argument
106
107           [% USE image('foo.gif', alt='Logo') %]
108

CATCHING ERRORS

110       If the image file cannot be found then the above methods will throw an
111       'Image' error.  You can enclose calls to these methods in a TRY...CATCH
112       block to catch any potential errors.
113
114           [% TRY;
115                image.width;
116              CATCH;
117                error;      # print error
118              END
119           %]
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USING Image::Info

122       At run time, the plugin tries to load Image::Info in preference to
123       Image::Size. If Image::Info is found, then some additional methods are
124       available, in addition to 'size', 'width', 'height', 'attr', and 'tag'.
125       These additional methods are named after the elements that Image::Info
126       retrieves from the image itself; see Image::Info for more details --
127       the types of methods available depend on the type of image.  These
128       additional methods will always include the following:
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130       file_media_type
131           This is the MIME type that is appropriate for the given file for‐
132           mat.  The corresponding value is a string like: "image/png" or
133           "image/jpeg".
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135       file_ext
136           The is the suggested file name extention for a file of the given
137           file format.  The value is a 3 letter, lowercase string like "png",
138           "jpg".
139
140       color_type
141           The value is a short string describing what kind of values the pix‐
142           els encode.  The value can be one of the following:
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144             Gray
145             GrayA
146             RGB
147             RGBA
148             CMYK
149             YCbCr
150             CIELab
151
152           These names can also be prefixed by "Indexed-" if the image is com‐
153           posed of indexes into a palette.  Of these, only "Indexed-RGB" is
154           likely to occur.
155
156           (It is similar to the TIFF field PhotometricInterpretation, but
157           this name was found to be too long, so we used the PNG inpired term
158           instead.)
159
160       resolution
161           The value of this field normally gives the physical size of the
162           image on screen or paper. When the unit specifier is missing then
163           this field denotes the squareness of pixels in the image.
164
165           The syntax of this field is:
166
167              <res> <unit>
168              <xres> "/" <yres> <unit>
169              <xres> "/" <yres>
170
171           The <res>, <xres> and <yres> fields are numbers.  The <unit> is a
172           string like "dpi", "dpm" or "dpcm" (denoting "dots per
173           inch/cm/meter).
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175       SamplesPerPixel
176           This says how many channels there are in the image.  For some image
177           formats this number might be higher than the number implied from
178           the "color_type".
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180       BitsPerSample
181           This says how many bits are used to encode each of samples.  The
182           value is a reference to an array containing numbers. The number of
183           elements in the array should be the same as "SamplesPerPixel".
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185       Comment
186           Textual comments found in the file.  The value is a reference to an
187           array if there are multiple comments found.
188
189       Interlace
190           If the image is interlaced, then this tell which interlace method
191           is used.
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193       Compression
194           This tell which compression algorithm is used.
195
196       Gamma
197           A number.
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AUTHOR

200       Andy Wardley <abw@wardley.org>
201
202       <http://wardley.org/⎪http://wardley.org/>
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VERSION

205       1.21, distributed as part of the Template Toolkit version 2.18,
206       released on 09 February 2007.
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COPYRIGHT

209         Copyright (C) 1996-2007 Andy Wardley.  All Rights Reserved.
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211       This module is free software; you can redistribute it and/or modify it
212       under the same terms as Perl itself.
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