Image::Scale can resize and keep transparency if you use the png format instead of gif. I tried this: 
#!/usr/bin/perl

use strict;
use warnings;
use Image::Scale;

my $img = Image::Scale->new('image.gif');     
$img->resize_gd(  { width => 150 } );
$img->save_png('newImage.png');

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In reply to Re: Resizing images with transparent background? by Khen1950fx
in thread Resizing images with transparent background? by Anonymous Monk

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