Template::Plugin::Image - Plugin access to image sizes
[% USE Image(filename) %]
[% Image.width %]
[% Image.height %]
[% Image.size.join(', ') %]
[% Image.attr %]
[% Image.tag %]
This plugin provides an interface to the the Image::Info manpage or the Image::Size manpage
modules for determining the size of image files.
You can specify the plugin name as either 'Image ' or 'image '. The
plugin object created will then have the same name. The file name of
the image should be specified as a positional or named argument.
[% # all these are valid, take your pick %]
[% USE Image('foo.gif') %]
[% USE image('bar.gif') %]
[% USE Image 'ping.gif' %]
[% USE image(name='baz.gif') %]
[% USE Image name='pong.gif' %]
A root parameter can be used to specify the location of the image file:
[% USE Image(root='/path/to/root', name='images/home.png') %]
# image path: /path/to/root/images/home.png
# img src: images/home.png
In cases where the image path and image url do not match up, specify the
file name directly:
[% USE Image(file='/path/to/home.png', name='/images/home.png') %]
The alt parameter can be used to specify an alternate name for the
image, for use in constructing an XHTML element (see the tag() method
below).
[% USE Image('home.png', alt="Home") %]
You can also provide an alternate name for an Image plugin object.
[% USE img1 = image 'foo.gif' %]
[% USE img2 = image 'bar.gif' %]
The name method returns the image file name.
[% img1.name %] # foo.gif
The width and height methods return the width and height of the
image, respectively. The size method returns a reference to a 2
element list containing the width and height.
[% USE image 'foo.gif' %]
width: [% image.width %]
height: [% image.height %]
size: [% image.size.join(', ') %]
The modtime method returns the modification time of the file in question,
suitable for use with the Date plugin, for example:
[% USE image 'foo.gif' %]
[% USE date %]
[% date.format(image.modtime, "%B, %e %Y") %]
The attr method returns the height and width as HTML/XML attributes.
[% USE image 'foo.gif' %]
[% image.attr %]
Typical output:
width="60" height="20"
The tag method returns a complete XHTML tag referencing the image.
[% USE image 'foo.gif' %]
[% image.tag %]
Typical output:
<img src="foo.gif" width="60" height="20" alt="" />
You can provide any additional attributes that should be added to the
XHTML tag.
[% USE image 'foo.gif' %]
[% image.tag(class="logo" alt="Logo") %]
Typical output:
<img src="foo.gif" width="60" height="20" alt="Logo" class="logo" />
Note that the alt attribute is mandatory in a strict XHTML img
element (even if it's empty) so it is always added even if you don't
explicitly provide a value for it. You can do so as an argument to
the tag method, as shown in the previous example, or as an argument
[% USE image('foo.gif', alt='Logo') %]
If the image file cannot be found then the above methods will throw an
Image error. You can enclose calls to these methods in a
TRY...CATCH block to catch any potential errors.
[% TRY;
image.width;
CATCH;
error; # print error
END
%]
At run time, the plugin tries to load the Image::Info manpage in preference to
the Image::Size manpage. If the Image::Info manpage is found, then some additional methods are
available, in addition to size , width , height , attr , and tag .
These additional methods are named after the elements that the Image::Info manpage
retrieves from the image itself. The types of methods available depend on the
type of image (see the Image::Info manpage for more details). These additional methods
will always include the following:
This is the MIME type that is appropriate for the given file format.
The corresponding value is a string like: ``image/png '' or ``image/jpeg ''.
The is the suggested file name extension for a file of the given
file format. The value is a 3 letter, lowercase string like
``png '', ``jpg ''.
The value is a short string describing what kind of values the pixels
encode. The value can be one of the following:
Gray
GrayA
RGB
RGBA
CMYK
YCbCr
CIELab
These names can also be prefixed by ``Indexed- '' if the image is
composed of indexes into a palette. Of these, only ``Indexed-RGB '' is
likely to occur.
(It is similar to the TIFF field PhotometricInterpretation, but this
name was found to be too long, so we used the PNG inspired term
instead.)
The value of this field normally gives the physical size of the image
on screen or paper. When the unit specifier is missing then this field
denotes the squareness of pixels in the image.
The syntax of this field is:
<res> <unit>
<xres> "/" <yres> <unit>
<xres> "/" <yres>
The <res> , <xres> and <yres> fields are
numbers. The <unit> is a string like dpi , dpm or
dpcm (denoting ``dots per inch/cm/meter).
This says how many channels there are in the image. For some image
formats this number might be higher than the number implied from the
color_type .
This says how many bits are used to encode each of samples. The value
is a reference to an array containing numbers. The number of elements
in the array should be the same as SamplesPerPixel .
Textual comments found in the file. The value is a reference to an
array if there are multiple comments found.
If the image is interlaced, then this returns the interlace type.
This returns the name of the compression algorithm is used.
A number indicating the gamma curve of the image (e.g. 2.2)
Andy Wardley <abw@wardley.org> http://wardley.org/
Copyright (C) 1996-2007 Andy Wardley. All Rights Reserved.
This module is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.
the Template::Plugin manpage, the Image::Info manpage
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