@@ -170,6 +170,12 @@ int64_t ff_ape_parse_tag(AVFormatContext *s)

     return tag_start;

 }

+static int string_is_ascii(const uint8_t *str)

+{

+    while (*str && *str >= 0x20 && *str <= 0x7e ) str++;

+    return !*str;

+}

+

 int ff_ape_write_tag(AVFormatContext *s)

 {

     AVDictionaryEntry *e = NULL;

@@ -193,8 +199,14 @@ int ff_ape_write_tag(AVFormatContext *s)

     ffio_fill(s->pb, 0, 8);             // reserved

     while ((e = av_dict_get(s->metadata, "", e, AV_DICT_IGNORE_SUFFIX))) {

-        int val_len = strlen(e->value);

+        int val_len;

+

+        if (!string_is_ascii(e->key)) {

+            av_log(s, AV_LOG_WARNING, "Non ASCII keys are not allowed\n");

+            continue;

+        }

+        val_len = strlen(e->value);

         avio_wl32(s->pb, val_len);            // value length

         avio_wl32(s->pb, 0);                  // item flags

         avio_put_str(s->pb, e->key);          // key