How would you determine the size of the image file automatically, if the font size was dynamic, without reserving a large image size?

Hmm, never done that. One idea: Generate a very large image, draw the text, use $font->bounding_box to get the dimensions of the drawn string, and finally crop the image accordingly.

How do I send the image to a web browser without saving the file first?

Try something like this:

my $img_data;
$img->write(data=>\$img_data,type=>'png')
  or die "Cannot dump image: ", $img->errstr;
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Now you've got the image in $img_data, so you can print it to STDOUT (or via CGI). If operating under CGI, don't forget to set the proper content-type.

--
#!/usr/bin/perl
for(ref bless{},just'another'perl'hacker){s-:+-$"-g&&print$_.$/}
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