AV_PICTURE_STRUCTURE_UNKNOWN  228 libavcodec/h264_parser.c     s->picture_structure = AV_PICTURE_STRUCTURE_UNKNOWN;
AV_PICTURE_STRUCTURE_UNKNOWN  100 libavcodec/hevc_parser.c     s->picture_structure = AV_PICTURE_STRUCTURE_UNKNOWN;
AV_PICTURE_STRUCTURE_UNKNOWN  103 libavcodec/hevc_sei.c         s->picture_struct = AV_PICTURE_STRUCTURE_UNKNOWN;