avformat/tty: make probing strict for first 8 bytes

5 years ago · 9216ad2e46
parent 5ad1c1a18a
commit 9216ad2e46
1 changed files with 7 additions and 1 deletions
--- a/libavformat/tty.c
+++ b/libavformat/tty.c
@ -56,7 +56,13 @@ static int read_probe(const AVProbeData *p)
    if (!p->buf_size)
        return 0;

-    for (int i = 0; i < p->buf_size; i++)
+    for (int i = 0; i < 8 && i < p->buf_size; i++)
+        cnt += !!isansicode(p->buf[i]);
+
+    if (cnt != 8)
+        return 0;
+
+    for (int i = 8; i < p->buf_size; i++)
        cnt += !!isansicode(p->buf[i]);

    return (cnt * 100LL / p->buf_size) * (cnt > 400) *