lavfi/silencedetect: Fix silence_end accuracy

libavfilter/af_silencedetect.c

@@ -92,7 +92,8 @@ static av_always_inline void update(SilenceDetectContext *s, AVFrame *insamples,
         }
     } else {
         if (s->start[channel] > INT64_MIN) {
-            int64_t end_pts = insamples->pts;
+            int64_t end_pts = insamples->pts + av_rescale_q(current_sample / s->channels,
+                    (AVRational){ 1, s->last_sample_rate }, time_base);
             int64_t duration_ts = end_pts - s->start[channel];
             set_meta(insamples, s->mono ? channel + 1 : 0, "silence_end",
                     av_ts2timestr(end_pts, &time_base));

tests/ref/fate/filter-metadata-silencedetect

@@ -17,7 +17,7 @@ pkt_pts=4800
 pkt_pts=5120
 pkt_pts=5440
 pkt_pts=5760
-pkt_pts=6080|tag:lavfi.silence_end=0.38|tag:lavfi.silence_duration=0.38
+pkt_pts=6080|tag:lavfi.silence_end=0.384813|tag:lavfi.silence_duration=0.384813
 pkt_pts=6400
 pkt_pts=6720
 pkt_pts=7040
@@ -97,7 +97,7 @@ pkt_pts=30400
 pkt_pts=30720
 pkt_pts=31040
 pkt_pts=31360
-pkt_pts=31680|tag:lavfi.silence_end=1.98|tag:lavfi.silence_duration=0.792438
+pkt_pts=31680|tag:lavfi.silence_end=1.99538|tag:lavfi.silence_duration=0.807813
 pkt_pts=32000
 pkt_pts=32320
 pkt_pts=32640
@@ -196,7 +196,7 @@ pkt_pts=62080
 pkt_pts=62400
 pkt_pts=62720
 pkt_pts=63040
-pkt_pts=63360|tag:lavfi.silence_end=3.96|tag:lavfi.silence_duration=1.015
+pkt_pts=63360|tag:lavfi.silence_end=3.97138|tag:lavfi.silence_duration=1.02638
 pkt_pts=63680
 pkt_pts=64000
 pkt_pts=64320
@@ -270,7 +270,7 @@ pkt_pts=85760
 pkt_pts=86080
 pkt_pts=86400
 pkt_pts=86720
-pkt_pts=87040|tag:lavfi.silence_end=5.44|tag:lavfi.silence_duration=0.683375
+pkt_pts=87040|tag:lavfi.silence_end=5.45|tag:lavfi.silence_duration=0.693375
 pkt_pts=87360
 pkt_pts=87680
 pkt_pts=88000
@@ -362,7 +362,7 @@ pkt_pts=115200
 pkt_pts=115520
 pkt_pts=115840
 pkt_pts=116160
-pkt_pts=116480|tag:lavfi.silence_end=7.28|tag:lavfi.silence_duration=1.00681
+pkt_pts=116480|tag:lavfi.silence_end=7.28569|tag:lavfi.silence_duration=1.0125
 pkt_pts=116800
 pkt_pts=117120
 pkt_pts=117440
@@ -452,7 +452,7 @@ pkt_pts=144000
 pkt_pts=144320
 pkt_pts=144640
 pkt_pts=144960
-pkt_pts=145280|tag:lavfi.silence_end=9.08|tag:lavfi.silence_duration=0.828937
+pkt_pts=145280|tag:lavfi.silence_end=9.08156|tag:lavfi.silence_duration=0.8305
 pkt_pts=145600
 pkt_pts=145920
 pkt_pts=146240