The spec requires me to display an image inside a Gtk2::Textview.

Sometimes the image must be displayed its original size. Sometimes it must be its original size, but surrounded by some empty 'padding'.

The script below is the closest I've been able to get so far. It uses Gtk2::Gdk::Pixbuf->scale to create the 'padding'.

However, the 'padding' is not empty space, as I'd hoped, but a blur of pixels from the edges of the original image.

Is there a simple way to remove the blur, or does this call for a different approach entirely?

#!/usr/bin/perl
package scaleme;

use strict;
use diagnostics;
use warnings;

use Gtk2 '-init';
use Glib qw(TRUE FALSE);

# Display this image
my $path = 'change_this_directory/cat.bmp';

# Open a Gtk2 window with a Gtk2::TextView 
my $window = Gtk2::Window->new('toplevel');
$window->set_title('scaleme');
$window->set_position('center');
$window->set_default_size(800, 600);
$window->signal_connect('delete-event' => sub {

    Gtk2->main_quit();
    exit;
});
            
my $frame = Gtk2::Frame->new();
$window->add($frame);

my $scrollWin = Gtk2::ScrolledWindow->new(undef, undef);
$frame->add($scrollWin);
$scrollWin->set_policy('automatic', 'automatic');     
$scrollWin->set_border_width(0);

my $textView = Gtk2::TextView->new;
$scrollWin->add_with_viewport($textView);

if (-e $path) {

    # Display a photo of a cat face
    my $pixbuf = Gtk2::Gdk::Pixbuf->new_from_file($path);

    my $buffer = $textView->get_buffer();
    $buffer->insert_pixbuf(
        $buffer->get_end_iter(),
        $pixbuf,
    );

    # Make the overall image 20% bigger, but the cat's face is its 
    #   original size (and centred in the middle)
    my $factor = 0.2;   
    my $w = $pixbuf->get_width();
    my $h = $pixbuf->get_height();

    my $pixbuf2 = Gtk2::Gdk::Pixbuf->new(
        'GDK_COLORSPACE_RGB',
        FALSE,
        $pixbuf->get_bits_per_sample(),
        ($w * (1 + $factor)),
        ($h * (1 + $factor)),
    );

    $pixbuf->scale(
        # $dest
        $pixbuf2,
        # $destx, $desty
        0,
        0,
        # $dest_width, $dest_height
        ($w * (1 + $factor)),
        ($h * (1 + $factor)),
        # $offset_x, $offset_y
        ($w * ($factor / 2)),
        ($h * ($factor / 2)),
        # $scale_x, $scale_y
        1,
        1,
        # $interp_type
        'GDK_INTERP_NEAREST',
     );

    $buffer->insert_pixbuf(
        $buffer->get_end_iter(),
        $pixbuf2,
    );
}

$window->show_all();   
Gtk2->main();
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