lavf/subviewerdec: Support higher sub-second precision.

Fixes ticket #8575.

libavformat/subviewerdec.c

@@ -56,11 +56,21 @@ static int read_ts(const char *s, int64_t *start, int *duration)
     int64_t end;
     int hh1, mm1, ss1, ms1;
     int hh2, mm2, ss2, ms2;
+    int multiplier = 1;
 
+    if (sscanf(s, "%u:%u:%u.%2u,%u:%u:%u.%2u",
+               &hh1, &mm1, &ss1, &ms1, &hh2, &mm2, &ss2, &ms2) == 8) {
+        multiplier = 10;
+    } else if (sscanf(s, "%u:%u:%u.%1u,%u:%u:%u.%1u",
+                      &hh1, &mm1, &ss1, &ms1, &hh2, &mm2, &ss2, &ms2) == 8) {
+        multiplier = 100;
+    }
     if (sscanf(s, "%u:%u:%u.%u,%u:%u:%u.%u",
                &hh1, &mm1, &ss1, &ms1, &hh2, &mm2, &ss2, &ms2) == 8) {
-        end    = (hh2*3600LL + mm2*60LL + ss2) * 100LL + ms2;
-        *start = (hh1*3600LL + mm1*60LL + ss1) * 100LL + ms1;
+        ms1 = FFMIN(ms1, 999);
+        ms2 = FFMIN(ms2, 999);
+        end    = (hh2*3600LL + mm2*60LL + ss2) * 1000LL + ms2 * multiplier;
+        *start = (hh1*3600LL + mm1*60LL + ss1) * 1000LL + ms1 * multiplier;
         *duration = end - *start;
         return 0;
     }
@@ -84,7 +94,7 @@ static int subviewer_read_header(AVFormatContext *s)
         return res;
     if (avio_rb24(s->pb) != 0xefbbbf)
         avio_seek(s->pb, -3, SEEK_CUR);
-    avpriv_set_pts_info(st, 64, 1, 100);
+    avpriv_set_pts_info(st, 64, 1, 1000);
     st->codecpar->codec_type = AVMEDIA_TYPE_SUBTITLE;
     st->codecpar->codec_id   = AV_CODEC_ID_SUBVIEWER;