initial dts fix

Originally committed as revision 3555 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/mpeg.c

@@ -1016,19 +1016,6 @@ static int mpeg_mux_write_packet(AVFormatContext *ctx, AVPacket *pkt)
     pts= pkt->pts;
     dts= pkt->dts;
 
-    if(s->is_svcd) {
-        /* offset pts and dts slightly into the future to be able
-           to do the compatibility fix below.*/
-        pts += 2;
-        dts += 2;
-
-        if (stream->packet_number == 0 && dts == pts)
-            /* For the very first packet we want to force the DTS to be included.
-               This increases compatibility with lots of DVD players.
-               Since the MPEG-2 standard mandates that DTS is only written when
-               it is different from PTS we have to move it slightly into the past.*/
-            dts -= 2;
-    }
     if(s->is_vcd) {
         /* We have to offset the PTS, so that it is consistent with the SCR.
            SCR starts at 36000, but the first two packs contain only padding

libavformat/utils.c

@@ -1979,8 +1979,8 @@ static void compute_pkt_fields2(AVStream *st, AVPacket *pkt){
 static void truncate_ts(AVStream *st, AVPacket *pkt){
     int64_t pts_mask = (2LL << (st->pts_wrap_bits-1)) - 1;
     
-    if(pkt->dts < 0)
-        pkt->dts= 0;  //this happens for low_delay=0 and b frames, FIXME, needs further invstigation about what we should do here
+//    if(pkt->dts < 0)
+//        pkt->dts= 0;  //this happens for low_delay=0 and b frames, FIXME, needs further invstigation about what we should do here
     
     pkt->pts &= pts_mask;
     pkt->dts &= pts_mask;

tests/libav.regression.ref

@@ -7,7 +7,7 @@ ffmpeg regression test
 ./data/b-libav.asf CRC=750f18c7
 1cbf838e659d7fc3d3e33f4187b91f6c *./data/b-libav.rm
 360251 ./data/b-libav.rm
-65af12e9d9e8eb76af5efdadf769d7d7 *./data/b-libav.mpg
+7aeebe6bf43c0c1219e41ce082a47051 *./data/b-libav.mpg
 387072 ./data/b-libav.mpg
 ./data/b-libav.mpg CRC=16c74225
 57a8dfc7926802bb337a9d8918de94a8 *./data/b-libav.swf