dont butcher start_time in av_estimate_timings_from_bit_rate()

from a patch by neilb suse de


git-svn-id: file:///var/local/repositories/ffmpeg/trunk@10140 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b

libavformat/utils.c

@@ -1460,14 +1460,11 @@ static void av_estimate_timings_from_bit_rate(AVFormatContext *ic)
             for(i = 0; i < ic->nb_streams; i++) {
                 st = ic->streams[i];
                 duration= av_rescale(8*filesize, st->time_base.den, ic->bit_rate*(int64_t)st->time_base.num);
-                if (st->start_time == AV_NOPTS_VALUE ||
-                    st->duration == AV_NOPTS_VALUE) {
-                    st->start_time = 0;
+                if (st->duration == AV_NOPTS_VALUE)
                     st->duration = duration;
             }
         }
     }
-    }
 }
 
 #define DURATION_MAX_READ_SIZE 250000