static int read_probe(const AVProbeData *p)
{
    int cnt = 0;

    for (int i = 0; i < p->buf_size; i++)
        cnt += !!isansicode(p->buf[i]);

    return (cnt * 100LL / p->buf_size) * (cnt > 400) *
        !!av_match_ext(p->filename, tty_extensions);
}