oggdec: Make sure start time correction is applied once to each stream

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

libavformat/oggdec.c

@@ -452,6 +452,7 @@ static int ogg_get_length(AVFormatContext *s)
     struct ogg *ogg = s->priv_data;
     int i;
     int64_t size, end;
+    int streams_left=0;
 
     if(!s->pb->seekable)
         return 0;
@@ -473,8 +474,14 @@ static int ogg_get_length(AVFormatContext *s)
             ogg->streams[i].codec) {
             s->streams[i]->duration =
                 ogg_gptopts (s, i, ogg->streams[i].granule, NULL);
-            if (s->streams[i]->start_time != AV_NOPTS_VALUE)
+            if (s->streams[i]->start_time != AV_NOPTS_VALUE){
                 s->streams[i]->duration -= s->streams[i]->start_time;
+                streams_left-= (ogg->streams[i].got_start==-1);
+                ogg->streams[i].got_start= 1;
+            }else if(!ogg->streams[i].got_start){
+                ogg->streams[i].got_start= -1;
+                streams_left++;
+            }
         }
     }
 
@@ -485,9 +492,14 @@ static int ogg_get_length(AVFormatContext *s)
     while (!ogg_read_page (s, &i)){
         if (ogg->streams[i].granule != -1 && ogg->streams[i].granule != 0 &&
             ogg->streams[i].codec) {
-            s->streams[i]->duration -=
-                ogg_gptopts (s, i, ogg->streams[i].granule, NULL);
-            break;
+            if(s->streams[i]->duration && s->streams[i]->start_time == AV_NOPTS_VALUE && !ogg->streams[i].got_start){
+                s->streams[i]->duration -=
+                    ogg_gptopts (s, i, ogg->streams[i].granule, NULL);
+                ogg->streams[i].got_start= 1;
+                streams_left--;
+            }
+            if(streams_left<=0)
+                break;
         }
     }
     ogg_restore (s, 0);

libavformat/oggdec.h

@@ -75,6 +75,7 @@ struct ogg_stream {
     int incomplete; ///< whether we're expecting a continuation in the next page
     int page_end;   ///< current packet is the last one completed in the page
     int keyframe_seek;
+    int got_start;
     void *private;
 };