mxfdec: Rescale audio stream duration from EditRate to SampleRate

Since 83cab07 audio stream time bases are based on SampleRate, not EditRate.
This fixes trac ticket #2029 and a few seeking issues.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavformat/mxfdec.c

@@ -134,6 +134,7 @@ typedef struct {
     AVRational edit_rate;
     int intra_only;
     uint64_t sample_count;
+    int64_t original_duration;  ///< duration before multiplying st->duration by SampleRate/EditRate
 } MXFTrack;
 
 typedef struct {
@@ -1445,7 +1446,7 @@ static int mxf_parse_structural_metadata(MXFContext *mxf)
         }
         st->id = source_track->track_id;
         st->priv_data = source_track;
-        st->duration = component->duration;
+        source_track->original_duration = st->duration = component->duration;
         if (st->duration == -1)
             st->duration = AV_NOPTS_VALUE;
         st->start_time = component->start_position;
@@ -1457,6 +1458,9 @@ static int mxf_parse_structural_metadata(MXFContext *mxf)
         }
         avpriv_set_pts_info(st, 64, material_track->edit_rate.den, material_track->edit_rate.num);
 
+        /* ensure SourceTrack EditRate == MaterialTrack EditRate since only the former is accessible via st->priv_data */
+        source_track->edit_rate = material_track->edit_rate;
+
         PRINT_KEY(mxf->fc, "data definition   ul", source_track->sequence->data_definition_ul);
         codec_ul = mxf_get_codec_ul(ff_mxf_data_definition_uls, &source_track->sequence->data_definition_ul);
         st->codec->codec_type = codec_ul->id;
@@ -1570,6 +1574,10 @@ static int mxf_parse_structural_metadata(MXFContext *mxf)
                 avpriv_set_pts_info(st, 64, 1, 48000);
             }
 
+            /* if duration is set, rescale it from EditRate to SampleRate */
+            if (st->duration != AV_NOPTS_VALUE)
+                st->duration = av_rescale_q(st->duration, av_inv_q(material_track->edit_rate), st->time_base);
+
             /* TODO: implement AV_CODEC_ID_RAWAUDIO */
             if (st->codec->codec_id == AV_CODEC_ID_PCM_S16LE) {
                 if (descriptor->bits_per_sample > 16 && descriptor->bits_per_sample <= 24)
@@ -2298,6 +2306,11 @@ static int mxf_read_seek(AVFormatContext *s, int stream_index, int64_t sample_ti
     int64_t seekpos;
     int i, ret;
     MXFIndexTable *t;
+    MXFTrack *source_track = st->priv_data;
+
+    /* if audio then truncate sample_time to EditRate */
+    if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO)
+        sample_time = av_rescale_q(sample_time, st->time_base, av_inv_q(source_track->edit_rate));
 
     if (mxf->nb_index_tables <= 0) {
     if (!s->bit_rate)
@@ -2323,7 +2336,7 @@ static int mxf_read_seek(AVFormatContext *s, int stream_index, int64_t sample_ti
         } else {
             /* no IndexEntryArray (one or more CBR segments)
              * make sure we don't seek past the end */
-            sample_time = FFMIN(sample_time, st->duration - 1);
+            sample_time = FFMIN(sample_time, source_track->original_duration - 1);
         }
 
         if ((ret = mxf_edit_unit_absolute_offset(mxf, t, sample_time, &sample_time, &seekpos, 1)) << 0)

tests/ref/seek/lavf-mxf

@@ -30,7 +30,7 @@ ret: 0         st: 0 flags:1  ts: 2.400000
 ret: 0         st: 0 flags:1 dts: 0.840000 pts: 0.960000 pos: 460288 size: 24711
 ret:-1         st: 1 flags:0  ts: 1.306667
 ret: 0         st: 1 flags:1  ts: 0.200833
-ret: 0         st: 0 flags:1 dts: 0.840000 pts: 0.960000 pos: 460288 size: 24711
+ret: 0         st: 0 flags:1 dts:-0.040000 pts: 0.000000 pos:   6144 size: 24801
 ret: 0         st:-1 flags:0  ts:-0.904994
 ret: 0         st: 0 flags:1 dts:-0.040000 pts: 0.000000 pos:   6144 size: 24801
 ret: 0         st:-1 flags:1  ts: 1.989173

tests/ref/seek/lavf-mxf_d10

@@ -34,7 +34,7 @@ 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: 1 flags:1  ts: 0.200833
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:5117952 size:150000
+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
 ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:   6144 size:150000
 ret: 0         st:-1 flags:1  ts: 1.989173