You can get list of all registered filters and hooks in wordpress using global variables $wp_filter and $wp_actions. Please see following example.
Example 1 global $wp_filter , $wp_actions; echo '<pre>'; print_r( $wp_actions ); print_r( $wp_filter ); echo '</pre>';
If you want to get list of a specific filter then use as follows example.
Example 2 gloabl $wp_filter; $spec_filter = 'the_content'; echo '<pre>'; print_r( $wp_filter[ $spec_filter ] ); echo '</pre>';