diff --git a/themes/default/template/picture_content.tpl b/themes/default/template/picture_content.tpl
index 793c275ea..998902dbb 100644
--- a/themes/default/template/picture_content.tpl
+++ b/themes/default/template/picture_content.tpl
@@ -10,11 +10,11 @@
 <map name="map{$derivative->get_type()}">
 {assign var='size' value=$derivative->get_size()}
 {if isset($previous)}
-<area shape=rect coords="0,0,{$size[0]/4|@intval},{$size[1]}" href="{$previous.U_IMG}" title="{'Previous'|@translate} : {$previous.TITLE|@escape}" alt="{$previous.TITLE|@escape}">
+<area shape=rect coords="0,0,{($size[0]/4)|@intval},{$size[1]}" href="{$previous.U_IMG}" title="{'Previous'|@translate} : {$previous.TITLE|@escape}" alt="{$previous.TITLE|@escape}">
 {/if}
-<area shape=rect coords="{$size[0]/4|@intval},0,{$size[0]/1.34|@intval},{$size[1]/4|@intval}" href="{$U_UP}" title="{'Thumbnails'|@translate}" alt="{'Thumbnails'|@translate}">
+<area shape=rect coords="{($size[0]/4)|@intval},0,{($size[0]/1.34)|@intval},{($size[1]/4)|@intval}" href="{$U_UP}" title="{'Thumbnails'|@translate}" alt="{'Thumbnails'|@translate}">
 {if isset($next)}
-<area shape=rect coords="{$size[0]/1.33|@intval},0,{$size[0]},{$size[1]}" href="{$next.U_IMG}" title="{'Next'|@translate} : {$next.TITLE|@escape}" alt="{$next.TITLE|@escape}">
+<area shape=rect coords="{($size[0]/1.33)|@intval},0,{$size[0]},{$size[1]}" href="{$next.U_IMG}" title="{'Next'|@translate} : {$next.TITLE|@escape}" alt="{$next.TITLE|@escape}">
 {/if}
 </map>
 {/strip}{/foreach}
\ No newline at end of file