ID_STRING          31 libavformat/ffmetadec.c     if(!memcmp(p->buf, ID_STRING, strlen(ID_STRING)))
ID_STRING          54 libavformat/ffmetaenc.c     avio_write(s->pb, ID_STRING, sizeof(ID_STRING) - 1);
ID_STRING         770 libavformat/nutenc.c     avio_write(bc, ID_STRING, strlen(ID_STRING));