how to add the thread title to the images alt atribute????

[kootta]

in vbulletin the users posted images they have an empty alt attribute
like that
<img src="http://nulled.ucoz.com/pictures/Clones/Qooy.jpg (https://vborg.vbsupport.ru/view-source:http://nulled.ucoz.com/pictures/Clones/Qooy.jpg)" alt="" border="0"><br>

the alt attribute is empty i want to add the thread title in that attribute
so the code look like
<img src="http://nulled.ucoz.com/pictures/Clones/Qooy.jpg (https://vborg.vbsupport.ru/view-source:http://nulled.ucoz.com/pictures/Clones/Qooy.jpg)" alt="how to add the thread title to the images alt atribute????" border="0"><br>


i hope someone can help or someone guide me to a product doing the same?
thanks