next_post_link & timthumb

hello

I want to insert the image (croped and resized by the script timthumb)of the next post into next_post_link() but i dont know how to do…?

i just have :
<?php previous_post_link('%link','$what_i_want')

and today $what_i_want is :
<img class="miniature" src="<?php bloginfo('template_directory'); ?>/scripts/timthumb.php?src=<?php echo get_post_meta($post->ID, "thumb", $single = true); ?>&h=150&w=&150&zc=1" alt="<?php the_title(); ?>" width="100" height="100" />

but it doesn’t match…

If somebody have my answer ?? ?
sainkiou

Estelle