GUIDE: Automatically resize phpBB avatars in post displays

1. Open the includes/functions_display.php file in a text editor.
2. Above the return '<img src="' . (str_replace( … line, insert the code:

   $inputwidth = 100;
   $inputheight = 100;
   
   // So then if the image is wider rather than taller, set the width and figure out the height
   if (($avatar_width/$avatar_height) > ($inputwidth/$inputheight)) {
    $outputwidth = $inputwidth;
    $outputheight = ($inputwidth * $avatar_height)/ $avatar_width;
   }
   // And if the image is taller rather than wider, then set the height and figure out the width
   elseif (($avatar_width/$avatar_height) < ($inputwidth/$inputheight)) {
    $outputwidth = ($inputheight * $avatar_width)/ $avatar_height;
    $outputheight = $inputheight;
   }
   // And because it is entirely possible that the image could be the exact same size/aspect ratio of the desired area, so we have that covered as well
   elseif (($avatar_width/$avatar_height) == ($inputwidth/$inputheight)) {
    $outputwidth = $inputwidth;
    $outputheight = $inputheight;
   }

3. Change the $inputwidth and $inputheight variables to suit your needs.
4. Replace the return '<img src="' . (str_replace( … line with:

   return '<img src="' . (str_replace(' ', '%20', $avatar_img)) . '" width="' . $outputwidth . '" height="' . $outputheight . '" alt="' . ((!empty($user->lang[$alt])) ? $user->lang[$alt] : $alt) . '" />';