@param req_flags requested flags for the options to show. Show only the
options for which it is opt->flags & req_flags.
@param rej_flags rejected flags for the options to show. Show only the
options for which it is !(opt->flags & req_flags).
@param av_log_obj log context to use for showing the options
Show the obj options.
@param req_flags requested flags for the options to show. Show only the options for which it is opt->flags & req_flags. @param rej_flags rejected flags for the options to show. Show only the options for which it is !(opt->flags & req_flags). @param av_log_obj log context to use for showing the options