diff --git a/libavformat/flvenc.c b/libavformat/flvenc.c
index c16f8ebb4a..1d8af3388d 100644
--- a/libavformat/flvenc.c
+++ b/libavformat/flvenc.c
@@ -209,8 +209,6 @@ static int flv_write_header(AVFormatContext *s)
             if (s->streams[i]->avg_frame_rate.den &&
                 s->streams[i]->avg_frame_rate.num) {
                 framerate = av_q2d(s->streams[i]->avg_frame_rate);
-            } else {
-                framerate = 1 / av_q2d(s->streams[i]->codec->time_base);
             }
             if (video_enc) {
                 av_log(s, AV_LOG_ERROR,
@@ -317,8 +315,10 @@ static int flv_write_header(AVFormatContext *s)
         put_amf_string(pb, "videodatarate");
         put_amf_double(pb, video_enc->bit_rate / 1024.0);
 
-        put_amf_string(pb, "framerate");
-        put_amf_double(pb, framerate);
+        if (framerate != 0.0) {
+            put_amf_string(pb, "framerate");
+            put_amf_double(pb, framerate);
+        }
 
         put_amf_string(pb, "videocodecid");
         put_amf_double(pb, video_enc->codec_tag);