| GD::Thumbnail - Thumbnail maker for GD |
GD::Thumbnail - Thumbnail maker for GD
use GD::Thumbnail;
my $thumb = GD::Thumbnail->new;
my $raw = $thumb->create('test.jpg', 80, 2);
my $mime = $thumb->mime;
warn sprintf "Dimension: %sx%s\n", $thumb->width, $thumb->height;
open IMG, ">thumb.$mime" or die "Error: $!";
binmode IMG;
print IMG $raw;
close IMG;
or
use CGI qw(:standard);
use GD::Thumbnail;
my $thumb = GD::Thumbnail->new;
my $raw = $thumb->create('test.jpg', 80, 2);
my $mime = $thumb->mime;
binmode STDOUT;
print header(-type => "image/$mime");
print $raw;
This document describes version 1.41 of GD::Thumbnail
released on 9 September 2012.
This is a thumbnail maker. Thumbnails are smaller versions of the original image/graphic/picture and are used for preview purposes, where bigger images can take a long time to load. They are also used in image galleries to preview a lot of images at a time.
This module also has the capability to add information strips about the original image. Original image's size (in bytes) and resolution & mime type can be added to the thumbnail's upper and lower parts. This feature can be useful for web software (image galleries or forums).
This is a Yet Another type of module. There are several
other thumbnail modules on CPAN, but they simply don't have
the features I need, so this module is written to increase
the thumbnail generator population on CPAN.
The module can raise an exception if something goes wrong.
So, you may have to use an eval block to catch them.
All color parameters must be passed as a three element array reference:
$color = [$RED, $GREEN, $BLUE]; $black = [ 0, 0, 0];
Object constructor. Accepts arguments in key => value
format.
my $thumb = GD::Thumbnail->new(%args);
If you want information strips (see create), but you don't want to get a longer image, set this to a true value, and the information strips will not affect the image height (but the actual thumbnail image will be smaller).
Alters the information text font. You can set this to Small,
Large, MediumBold, Tiny or Giant (all are case-insensitive).
Default value is Tiny, which is best for smaller images. If you
want to use bigger thumbnails, you can alter the used font via this
argument. It may also be useful for adding size & resolution
information to existing images. But beware that GD output size may
be smaller than the actual image and image quality may also differ.
You'll get a square thumbnail, if this is set to true. If the
original image is not a square, the empty parts will be filled
with blank (color is the same as strip_color) instead of
stretching the image in x or y dimension or clipping
it. If, however, square is set to crop, you'll get a
cropped square thumbnail.
Beware that enabling this option will also auto-enable the
overlay option, since it is needed for a square image.
If set to true, a 1x1 pixel border will be added to the final image.
Controls the frame color. Default is black.
Sets the info strip background color. Default is black. You must pass it as a three element array reference containing the red, green, blue values:
$thumb = GD::Thumbnail->new(
strip_color => [255, 0, 0]
);
Sets the info strip text color. Default is white. You must pass it as a three element array reference containing the red, green, blue values:
$thumb = GD::Thumbnail->new(
info_color => [255, 255, 255]
);
You can alter the thumbnail mime with this parameter.
Can be set to: png, jpeg or gif.
If set to true, the resulting dimensions will take the original image dimensions into consideration. Disabled by default.
Creates the thumbnail and returns the raw image data.
create() accepts three arguments:
my $raw = $thumb->create($image , $max, $info);
my $raw = $thumb->create('test.jpg', 80, 1 );
Can be a file path, a file handle or raw binary data.
Defines the maximum width of the thumbnail either in pixels or
percentage. You'll get a warning, if info parameter is set
and your max value is to small to fit an info text.
If info parameter is not set, or it has a false value, you'll get a normal thumbnail image:
_____________
| ........... |
| ........... |
| ...IMAGE... |
| ........... |
| ........... |
|_____________|
If you set it to 1, original image's dimensions and mime will be
added below the thumbnail:
_____________
| ........... |
| ........... |
| ...IMAGE... |
| ........... |
| ........... |
|_____________|
| 20x20 JPEG |
-------------
If you set it to 2, the byte size of the image will be added
to the top of the thumbnail:
_____________
| 25 KB |
|-------------|
| ........... |
| ........... |
| ...IMAGE... |
| ........... |
| ........... |
|_____________|
| 20x20 JPEG |
-------------
As you can see from the examples above, with the default options,
thumbnail image dimension is constant when adding information strips
(i.e.: strips don't overlay, but attached to upper and lower parts of
thumbnail). Each info strip increases thumbnail height by 8 pixels
(if the default tiny GD font Tiny is used).
But see the overlay and square options in new to alter this
behavior. You may also need to increase max value if square is
enabled.
Returns the thumbnail mime. Must be called after create.
Returns the thumbnail width in pixels. Must be called after create.
Returns the thumbnail height in pixels. Must be called after create.
You may get a warning, if there is something odd.
GIF format is not supported by this version (%f) of GD''
You have an old version of GD and your original image is a GIF
image. Also, the code may die after this warning.
max argument to create is too small to fit information.
Either disable info parameter or increase max value.
You can reverse the strip and info colors and then add a frame to the thumbnail to create a picture frame effect:
my $thumb = GD::Thumbnail->new(
strip_color => [255, 255, 255],
info_color => [ 0, 0, 0],
square => 1,
frame => 1,
);
my $raw = $thumb->create('test.jpg', 100, 2);
If you have a set of images with the same dimensions, you may use a percentage instead of a constant value:
my $raw = $thumb->create('test.jpg', '10%', 2);
Resulting thumbnail will be 90% smaller (x-y dimensions) than the original image.
Supported image types are limited with GD types, which include
png, jpeg and gif and some others. See GD for more information.
Usage of any other image type will be resulted with a fatal
error.
GD, the Image::Thumbnail manpage, the GD::Image::Thumbnail manpage, the Image::GD::Thumbnail manpage the Image::Magick::Thumbnail manpage, the Image::Magick::Thumbnail::Fixed manpage.
Burak Gursoy <burak@cpan.org>.
Copyright 2006 - 2012 Burak Gursoy. All rights reserved.
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.14.2 or, at your option, any later version of Perl 5 you may have available. =cut
| GD::Thumbnail - Thumbnail maker for GD |