open FILE,"filename";
read FILE,$file,100000;
close FILE;

##</code><code>##

@lines = split(/\<IMG/,$file);

##</code><code>##

$newfile = shift @lines;

##</code><code>##

foreach $line (@lines) {
  $pos = index($line,'>');
  $tag = substr($line,0,$pos+1);
  $restofline = substr($line,$pos+1);
  $tag =~ s/SRC\=\"(.*?)\"/SRC\=\"$newurls{$1}\"/gi;
  $newfile .= $tag . $restofline . "\n";
}

##</code><code>##

print $newfile;