Thanks a lot but I'm incapable of building Gtk2. It may be possible but seems not to worth the effort as of yet. I would rather put something to work with the means easily accesible. With Imager suggested by Anonymous Monk I was able to put together this code: 
use Imager;

my $icon_width=128;
my $icon_height=128;
  
my $image = Imager->new(xsize => $icon_width, ysize => $icon_height);
  
$image->box(
        xmin=>0,
        ymin=>0,
        xmax=>$icon_width-1,
        ymax => $icon_height-1,
        filled => 1, color => '#ffffff'
    );
  
my $font_filename = 'C:/Windows/Fonts/arialbd.ttf';
my $font = Imager::Font->new(file=>$font_filename)  or die "Cannot loa
+d $font_filename: ", Imager->errstr;
  
print "Enter number: ";my $text=<>;chomp($text);

my $text_size = 96;
  
$font->align(
        string => $text,
        size => $text_size,
        color => '#000000',
        x => $image->getwidth/2,
        y => $image->getheight/2,
        halign => 'center',
        valign => 'center',
        image => $image
    );
  
$image->write(file=>'number.ico') or die 'Cannot save image: ', $image
+->errstr;

[download]
It is a little bit weird (my be this is not the right font for this) but it works.

In reply to Re^2: Icon generation on the fly by chessgui
in thread Icon generation on the fly by chessgui

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.