avformat/mxfdec: fix last packet timestamps

The current edit unit cannot be reliably determined for the last packet of a
video stream, because we can't query the start offset of the next edit unit
from the index. This caused missing timestamps for the last video packet.

Therefore from now on, we allow setting the PTS even if we are not sure of the
current edit unit if mxf_set_current_edit_unit returned a specific failure, and
the assumed current edit unit is the last.

Fixes last packet timestamp of:
ffprobe -fflags nofillin -show_packets tests/data/lavf/lavf.mxf -select_streams v
Signed-off-by: Marton Balint <cus@passwd.hu>

libavformat/mxfdec.c

@@ -2976,7 +2976,7 @@ static int64_t mxf_set_current_edit_unit(MXFContext *mxf, int64_t current_offset
     /* find mxf->current_edit_unit so that the next edit unit starts ahead of current_offset */
     while (mxf->current_edit_unit >= 0) {
         if (mxf_edit_unit_absolute_offset(mxf, t, mxf->current_edit_unit + 1, NULL, &next_ofs, 0) < 0)
-            return -1;
+            return -2;
 
         if (next_ofs <= last_ofs) {
             /* large next_ofs didn't change or current_edit_unit wrapped
@@ -3065,7 +3065,7 @@ static int mxf_set_pts(MXFContext *mxf, AVStream *st, AVPacket *pkt, int64_t nex
     AVCodecParameters *par = st->codecpar;
     MXFTrack *track = st->priv_data;
 
-    if (par->codec_type == AVMEDIA_TYPE_VIDEO && next_ofs >= 0) {
+    if (par->codec_type == AVMEDIA_TYPE_VIDEO && (next_ofs >= 0 || next_ofs == -2 && st->duration == mxf->current_edit_unit + 1)) {
         /* mxf->current_edit_unit good - see if we have an
          * index table to derive timestamps from */
         MXFIndexTable *t = &mxf->index_tables[0];

tests/ref/seek/lavf-mxf_d10

@@ -8,9 +8,9 @@ ret: 0         st: 0 flags:1 dts: 0.800000 pts: 0.800000 pos:4265984 size:150000
 ret: 0         st: 0 flags:1  ts:-0.320000
 ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:   6144 size:150000
 ret: 0         st: 1 flags:0  ts: 2.576667
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:5117952 size:150000
+ret: 0         st: 0 flags:1 dts: 0.960000 pts: 0.960000 pos:5117952 size:150000
 ret: 0         st: 1 flags:1  ts: 1.470833
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:5117952 size:150000
+ret: 0         st: 0 flags:1 dts: 0.960000 pts: 0.960000 pos:5117952 size:150000
 ret: 0         st:-1 flags:0  ts: 0.365002
 ret: 0         st: 0 flags:1 dts: 0.360000 pts: 0.360000 pos:1923072 size:150000
 ret: 0         st:-1 flags:1  ts:-0.740831
@@ -22,7 +22,7 @@ ret: 0         st: 0 flags:1 dts: 0.960000 pts: 0.960000 pos:5117952 size:150000
 ret: 0         st: 1 flags:0  ts:-0.058333
 ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:   6144 size:150000
 ret: 0         st: 1 flags:1  ts: 2.835833
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:5117952 size:150000
+ret: 0         st: 0 flags:1 dts: 0.960000 pts: 0.960000 pos:5117952 size:150000
 ret: 0         st:-1 flags:0  ts: 1.730004
 ret: 0         st: 0 flags:1 dts: 0.960000 pts: 0.960000 pos:5117952 size:150000
 ret: 0         st:-1 flags:1  ts: 0.624171
@@ -32,7 +32,7 @@ ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:   6144 size:150000
 ret: 0         st: 0 flags:1  ts: 2.400000
 ret: 0         st: 0 flags:1 dts: 0.960000 pts: 0.960000 pos:5117952 size:150000
 ret: 0         st: 1 flags:0  ts: 1.306667
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:5117952 size:150000
+ret: 0         st: 0 flags:1 dts: 0.960000 pts: 0.960000 pos:5117952 size:150000
 ret: 0         st: 1 flags:1  ts: 0.200833
 ret: 0         st: 0 flags:1 dts: 0.200000 pts: 0.200000 pos:1071104 size:150000
 ret: 0         st:-1 flags:0  ts:-0.904994
@@ -44,9 +44,9 @@ ret: 0         st: 0 flags:1 dts: 0.880000 pts: 0.880000 pos:4691968 size:150000
 ret: 0         st: 0 flags:1  ts:-0.240000
 ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:   6144 size:150000
 ret: 0         st: 1 flags:0  ts: 2.671667
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:5117952 size:150000
+ret: 0         st: 0 flags:1 dts: 0.960000 pts: 0.960000 pos:5117952 size:150000
 ret: 0         st: 1 flags:1  ts: 1.565833
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:5117952 size:150000
+ret: 0         st: 0 flags:1 dts: 0.960000 pts: 0.960000 pos:5117952 size:150000
 ret: 0         st:-1 flags:0  ts: 0.460008
 ret: 0         st: 0 flags:1 dts: 0.480000 pts: 0.480000 pos:2562048 size:150000
 ret: 0         st:-1 flags:1  ts:-0.645825