Try to find out correct start time to make seeking faster and add some

extra checks to make sure the seeking function will not hang forever.

Originally committed as revision 5814 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 32 insertions, 4 deletions

diff --git a/libavformat/ogg2.c b/libavformat/ogg2.c
index 2af5a4f9aa..254415b7a3 100644
--- a/libavformat/ogg2.c
+++ b/libavformat/ogg2.c
@@ -201,7 +201,6 @@ ogg_new_stream (AVFormatContext * s, uint32_t serial)
         return AVERROR_NOMEM;
 
     av_set_pts_info(st, 64, 1, 1000000);
-    st->start_time = 0;
 
     return idx;
 }
@@ -495,6 +494,16 @@ ogg_get_length (AVFormatContext * s)
 
     ogg->size = size;
     ogg_restore (s, 0);
+    ogg_save (s);
+    while (ogg_read_page (s, &i)) {
+        if (i == idx && ogg->streams[i].granule != -1 && ogg->streams[i].granule != 0)
+            break;
+    }
+    if (i == idx) {
+        s->streams[idx]->start_time = ogg_gptopts (s, idx, ogg->streams[idx].granule);
+        s->streams[idx]->duration -= s->streams[idx]->start_time;
+    }
+    ogg_restore (s, 0);
 
     return 0;
 }
@@ -572,12 +581,14 @@ ogg_read_seek (AVFormatContext * s, int stream_index, int64_t target_ts,
     ogg_t *ogg = s->priv_data;
     ByteIOContext *bc = &s->pb;
     uint64_t min = 0, max = ogg->size;
-    uint64_t tmin = 0, tmax = st->duration;
+    uint64_t tmin = st->start_time, tmax = st->start_time + st->duration;
     int64_t pts = AV_NOPTS_VALUE;
 
     ogg_save (s);
 
-    while (min <= max){
+    if ((uint64_t)target_ts < tmin || target_ts < 0)
+        target_ts = tmin;
+    while (min <= max && tmin < tmax){
         uint64_t p = min + (max - min) * (target_ts - tmin) / (tmax - tmin);
         int i = -1;
 
@@ -599,9 +610,25 @@ ogg_read_seek (AVFormatContext * s, int stream_index, int64_t target_ts,
             break;
 
         if (pts > target_ts){
+            if (max == p && tmax == pts) {
+                // probably our tmin is wrong, causing us to always end up too late in the file
+                tmin = (target_ts + tmin + 1) / 2;
+                if (tmin == target_ts) {
+                    url_fseek(bc, min, SEEK_SET);
+                    break;
+                }
+            }
             max = p;
             tmax = pts;
         }else{
+            if (min == p && tmin == pts) {
+                // probably our tmax is wrong, causing us to always end up too early in the file
+                tmax = (target_ts + tmax) / 2;
+                if (tmax == target_ts) {
+                    url_fseek(bc, max, SEEK_SET);
+                    break;
+                }
+            }
             min = p;
             tmin = pts;
         }
@@ -615,7 +642,8 @@ ogg_read_seek (AVFormatContext * s, int stream_index, int64_t target_ts,
         pts = AV_NOPTS_VALUE;
     }
 
-    return pts;
+    av_update_cur_dts(s, st, pts);
+    return 0;
 
 #if 0
     //later...