[TYPO3-english] Error php script

[Iban Cardona i Subiela]

Hello,

I have implemented this script in a extension:

<?php
shell_exec('gnome-web-photo -t 0 --mode=thumbnail -w 512 -s 256 
http://www.google.com /tmp/google.jpg');
?>

If I execute it in a browser I view this error: Cannot open display:

Somebody can help me please?

Thank you so much.
-- 
Serialnet SL

*  IBAN CARDONA I SUBIELA*
   SERIALNET NETWORKING I SOFTWARE LLIURE SL
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   08009 - Barcelona
   Tel. 93 265 09 37
http://www.serialnet.cat
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