- av_opt_set_int(s, "write_index", pos, AV_OPT_SEARCH_CHILDREN);
- av_opt_set_int(s, "file_size", file_size, AV_OPT_SEARCH_CHILDREN);
+ av_opt_set_int(s, "ffm_write_index", pos, AV_OPT_SEARCH_CHILDREN);
+ av_opt_set_int(s, "ffm_file_size", file_size, AV_OPT_SEARCH_CHILDREN);