Reducing a size of an image isn't always a guarantee that it'll take fewer bytes to store in a given image format.

You might consider using JPGs and reducing the quality until the size is sufficiently reduced.

By the way, thumbnails are easier than you show. To make a thumbnail that is 50%:

my $thumb = $src->Clone;
$thumb->scale(Geometry => '50%');
[download]

or to make a thumbnail that is less than 100x100 (in both directions), proportionally reduced (that is, if it's 400x200 originally, it'll be 100x50 when you're done):

my $thumb = $src->Clone;
$thumb->scale(Geometry => '100x100');
[download]

It just Does The Right Thing.

-- Randal L. Schwartz, Perl hacker
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