MAX_CUETRACKPOS_SIZE   90 libavformat/matroskaenc.c #define MAX_CUEPOINT_SIZE(num_tracks) 12 + MAX_CUETRACKPOS_SIZE*num_tracks
MAX_CUETRACKPOS_SIZE  381 libavformat/matroskaenc.c             track_positions = start_ebml_master(pb, MATROSKA_ID_CUETRACKPOSITION, MAX_CUETRACKPOS_SIZE);