if (track->mode == MODE_PSP) mov_write_uuid_tag_psp(pb,track);
static int mov_write_trak_tag(ByteIOContext *pb, MOVTrack* track){    int pos = url_ftell(pb);    put_be32(pb, 0); /* size */    put_tag(pb, "trak");    mov_write_tkhd_tag(pb, track);    mov_write_mdia_tag(pb, track);    return updateSize(pb, pos);}