If you want a simple GD solution with a small choice of fonts

  use GD;
  
  my $number = 223;
  # decide on which font you want
  #              width px    height px
  # gdTinyFont       5           8
  # gdSmallFont      6          12
  # gdMediumBoldFont 7          13
  # gdLargeFont      8          16
  # gdGiantFont      9          15


  # assume 3 digits Giant font with 5 px border
  # size of image length,height
  my $image = new GD::Image(37,25);       

  # background color ie yellow  
  $image->colorAllocate(255,255,0);    

  # define a brush color ie red
  my $red = $image->colorAllocate(255,0,0);
 
  # paint some text on the canvas
  $image->string(gdGiantFont,5,5,$number,$red);

  # create png
  open(PNG,">$number.png");
  binmode(PNG);
  print PNG $image->png;
  close(PNG);
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poj