Register a filter. This is only needed if you plan to use
avfilter_get_by_name later to lookup the AVFilter structure by name. A
filter can still by instantiated with avfilter_graph_alloc_filter even if it
is not registered.
@param filter the filter to register
@return 0 if the registration was successful, a negative value
otherwise
Register a filter. This is only needed if you plan to use avfilter_get_by_name later to lookup the AVFilter structure by name. A filter can still by instantiated with avfilter_graph_alloc_filter even if it is not registered.
@param filter the filter to register @return 0 if the registration was successful, a negative value otherwise