diff --git a/libavformat/mux.c b/libavformat/mux.c
index 1d8fedcc11..12dedeb498 100644
--- a/libavformat/mux.c
+++ b/libavformat/mux.c
@@ -225,6 +225,7 @@ static int init_muxer(AVFormatContext *s, AVDictionary **options)
     AVDictionary *tmp = NULL;
     AVCodecContext *codec = NULL;
     AVOutputFormat *of = s->oformat;
+    AVDictionaryEntry *e;
 
     if (options)
         av_dict_copy(&tmp, *options, 0);
@@ -351,6 +352,10 @@ static int init_muxer(AVFormatContext *s, AVDictionary **options)
         av_dict_set(&s->metadata, "encoder", NULL, 0);
     }
 
+    for (e = NULL; e = av_dict_get(s->metadata, "encoder-", e, AV_DICT_IGNORE_SUFFIX); ) {
+        av_dict_set(&s->metadata, e->key, NULL, 0);
+    }
+
     if (options) {
          av_dict_free(options);
          *options = tmp;