decsrt: fix p-to-p start time after seeking

Reader can skip data at the beginning of the file.  We were not
informing decsrt how much was skipped when pts_to_start caused the skip.

Fixes https://forum.handbrake.fr/viewtopic.php?f=11&t=36258

1 files changed, 5 insertions, 11 deletions

diff --git a/libhb/reader.c b/libhb/reader.c
index 71a961a1c..7f1e7cc1a 100644
--- a/libhb/reader.c
+++ b/libhb/reader.c
@@ -115,7 +115,7 @@ static int hb_reader_open( hb_work_private_t * r )
             // to start decoding early using r->pts_to_start
             hb_bd_seek_pts(r->bd, r->job->pts_to_start);
             r->duration -= r->job->pts_to_start;
-            r->job->pts_to_start = 0;
+            r->job->reader_pts_offset = r->job->pts_to_start;
             r->start_found = 1;
         }
         else
@@ -172,6 +172,7 @@ static int hb_reader_open( hb_work_private_t * r )
                 // first packet we get, subtract that from pts_to_start, and
                 // inspect the reset of the frames in sync.
                 r->duration -= r->job->pts_to_start;
+                r->job->reader_pts_offset = AV_NOPTS_VALUE;
             }
             else
             {
@@ -491,7 +492,8 @@ static int reader_work( hb_work_object_t * w, hb_buffer_t ** buf_in,
             // libav is allowing SSA subtitles to leak through that are
             // prior to the seek point.  So only make the adjustment to
             // pts_to_start after we see the next video buffer.
-            if (buf->s.id != r->job->title->video_id)
+            if (buf->s.id != r->job->title->video_id ||
+                buf->s.start == AV_NOPTS_VALUE)
             {
                 hb_buffer_close(&buf);
                 continue;
@@ -499,15 +501,7 @@ static int reader_work( hb_work_object_t * w, hb_buffer_t ** buf_in,
             // We will inspect the timestamps of each frame in sync
             // to skip from this seek point to the timestamp we
             // want to start at.
-            if (buf->s.start != AV_NOPTS_VALUE &&
-                buf->s.start < r->job->pts_to_start)
-            {
-                r->job->pts_to_start -= buf->s.start;
-            }
-            else if ( buf->s.start >= r->job->pts_to_start )
-            {
-                r->job->pts_to_start = 0;
-            }
+            r->job->reader_pts_offset = buf->s.start;
             r->start_found = 1;
         }