Merge remote-tracking branch 'qatar/master'

* qatar/master:
  cmdutils: Fix build with lavfi disabled
  flvenc: do not mux more than one stream per type

Merged-by: Michael Niedermayer <michaelni@gmx.at>

cmdutils.c

@@ -1635,6 +1635,7 @@ static void show_help_muxer(const char *name)
         show_help_children(fmt->priv_class, AV_OPT_FLAG_ENCODING_PARAM);
 }
 
+#if CONFIG_AVFILTER
 static void show_help_filter(const char *name)
 {
 #if CONFIG_AVFILTER
@@ -1682,6 +1683,7 @@ static void show_help_filter(const char *name)
            "can not to satisfy request\n");
 #endif
 }
+#endif
 
 int show_help(void *optctx, const char *opt, const char *arg)
 {
@@ -1703,8 +1705,10 @@ int show_help(void *optctx, const char *opt, const char *arg)
         show_help_demuxer(par);
     } else if (!strcmp(topic, "muxer")) {
         show_help_muxer(par);
+#if CONFIG_AVFILTER
     } else if (!strcmp(topic, "filter")) {
         show_help_filter(par);
+#endif
     } else {
         show_help_default(topic, par);
     }

libavformat/flvenc.c

@@ -212,6 +212,11 @@ static int flv_write_header(AVFormatContext *s)
             } else {
                 framerate = 1 / av_q2d(s->streams[i]->codec->time_base);
             }
+            if (video_enc) {
+                av_log(s, AV_LOG_ERROR,
+                       "at most one video stream is supported in flv\n");
+                return AVERROR(EINVAL);
+            }
             video_enc = enc;
             if (enc->codec_tag == 0) {
                 av_log(s, AV_LOG_ERROR, "Video codec '%s' for stream %d is not compatible with FLV\n",
@@ -220,6 +225,11 @@ static int flv_write_header(AVFormatContext *s)
             }
             break;
         case AVMEDIA_TYPE_AUDIO:
+            if (audio_enc) {
+                av_log(s, AV_LOG_ERROR,
+                       "at most one audio stream is supported in flv\n");
+                return AVERROR(EINVAL);
+            }
             audio_enc = enc;
             if (get_audio_flags(s, enc) < 0)
                 return AVERROR_INVALIDDATA;