diff --git a/libavcodec/x86/Makefile b/libavcodec/x86/Makefile
index 38ef867715..e1573c0161 100644
--- a/libavcodec/x86/Makefile
+++ b/libavcodec/x86/Makefile
@@ -31,6 +31,7 @@ OBJS-$(CONFIG_VP3DSP)                  += x86/vp3dsp_init.o
 OBJS-$(CONFIG_VP5_DECODER)             += x86/vp56dsp_init.o
 OBJS-$(CONFIG_VP6_DECODER)             += x86/vp56dsp_init.o
 OBJS-$(CONFIG_VP8_DECODER)             += x86/vp8dsp_init.o
+OBJS-$(CONFIG_WEBP_DECODER)            += x86/vp8dsp_init.o
 OBJS-$(CONFIG_XMM_CLOBBER_TEST)        += x86/w64xmmtest.o
 
 MMX-OBJS-$(CONFIG_DSPUTIL)             += x86/dsputil_mmx.o             \
@@ -85,6 +86,7 @@ YASM-OBJS-$(CONFIG_VORBIS_DECODER)     += x86/vorbisdsp.o
 YASM-OBJS-$(CONFIG_VP3DSP)             += x86/vp3dsp.o
 YASM-OBJS-$(CONFIG_VP6_DECODER)        += x86/vp56dsp.o
 YASM-OBJS-$(CONFIG_VP8_DECODER)        += x86/vp8dsp.o
+YASM-OBJS-$(CONFIG_WEBP_DECODER)       += x86/vp8dsp.o
 
 YASM-OBJS-$(CONFIG_DSPUTIL)            += x86/dsputil.o                 \
                                           x86/mpeg4qpel.o               \
diff --git a/libavformat/utils.c b/libavformat/utils.c
index d0393f9db2..0a12d8ab1d 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -2304,7 +2304,7 @@ static void fill_all_stream_timings(AVFormatContext *ic)
 static void estimate_timings_from_bit_rate(AVFormatContext *ic)
 {
     int64_t filesize, duration;
-    int bit_rate, i;
+    int bit_rate, i, show_warning = 0;
     AVStream *st;
 
     /* if bit_rate is already set, we believe it */
@@ -2329,10 +2329,13 @@ static void estimate_timings_from_bit_rate(AVFormatContext *ic)
                     && st->duration == AV_NOPTS_VALUE) {
                     duration= av_rescale(8*filesize, st->time_base.den, ic->bit_rate*(int64_t)st->time_base.num);
                     st->duration = duration;
+                    show_warning = 1;
                 }
             }
         }
     }
+    if (show_warning)
+        av_log(ic, AV_LOG_WARNING, "Estimating duration from bitrate, this may be inaccurate\n");
 }
 
 #define DURATION_MAX_READ_SIZE 250000LL
@@ -2440,7 +2443,6 @@ static void estimate_timings(AVFormatContext *ic, int64_t old_offset)
         fill_all_stream_timings(ic);
         ic->duration_estimation_method = AVFMT_DURATION_FROM_STREAM;
     } else {
-        av_log(ic, AV_LOG_WARNING, "Estimating duration from bitrate, this may be inaccurate\n");
         /* less precise: use bitrate info */
         estimate_timings_from_bit_rate(ic);
         ic->duration_estimation_method = AVFMT_DURATION_FROM_BITRATE;