diff --git a/libavcodec/opt.c b/libavcodec/opt.c
index c7218296f6..a6abcfc2e7 100644
--- a/libavcodec/opt.c
+++ b/libavcodec/opt.c
@@ -112,10 +112,8 @@ int av_set_string3(void *obj, const char *name, const char *val, int alloc, cons
     const AVOption *o= av_find_opt(obj, name, NULL, 0, 0);
     if (o_out)
         *o_out = o;
-    if(!o) {
-        av_log(obj, AV_LOG_ERROR, "Unknown option '%s'\n", name);
+    if(!o)
         return AVERROR(ENOENT);
-    }
     if(!val || o->offset<=0)
         return AVERROR(EINVAL);