X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;ds=sidebyside;f=libavformat%2Fmxfdec.c;h=e0a4b5bd11e6a9683506d363f4881c3160ea336f;hb=f50741147ccac999a8a3e8a15244cbe525537622;hp=4f30877f6d659e3ba3064d682bc112c709b08339;hpb=9492bb58eeea474158f9c523fd77395629117b57;p=ffmpeg

diff --git a/libavformat/mxfdec.c b/libavformat/mxfdec.c
index 4f30877f6d6..e0a4b5bd11e 100644
--- a/libavformat/mxfdec.c
+++ b/libavformat/mxfdec.c
@@ -91,6 +91,7 @@ typedef struct MXFPartition {
     int64_t index_byte_count;
     int pack_length;
     int64_t pack_ofs;               ///< absolute offset of pack in file, including run-in
+    int64_t body_offset;
 } MXFPartition;
 
 typedef struct MXFCryptoContext {
@@ -612,7 +613,7 @@ static int mxf_read_partition_pack(void *arg, AVIOContext *pb, int tag, int size
     partition->header_byte_count = avio_rb64(pb);
     partition->index_byte_count = avio_rb64(pb);
     partition->index_sid = avio_rb32(pb);
-    avio_skip(pb, 8);
+    partition->body_offset = avio_rb64(pb);
     partition->body_sid = avio_rb32(pb);
     if (avio_read(pb, op, sizeof(UID)) != sizeof(UID)) {
         av_log(mxf->fc, AV_LOG_ERROR, "Failed reading UID\n");
@@ -1309,9 +1310,15 @@ static int mxf_get_sorted_table_segments(MXFContext *mxf, int *nb_sorted_segment
              * We want the smallest values for the keys than what we currently have, unless this is the first such entry this time around.
              * If we come across an entry with the same IndexStartPosition but larger IndexDuration, then we'll prefer it over the one we currently have.
              */
-            if ((i == 0     || s->body_sid > last_body_sid || s->index_sid > last_index_sid || s->index_start_position > last_index_start) &&
-                (best == -1 || s->body_sid < best_body_sid || s->index_sid < best_index_sid || s->index_start_position < best_index_start ||
-                (s->index_start_position == best_index_start && s->index_duration > best_index_duration))) {
+            if ((i == 0 ||
+                 s->body_sid >  last_body_sid ||
+                 s->body_sid == last_body_sid && s->index_sid >  last_index_sid ||
+                 s->body_sid == last_body_sid && s->index_sid == last_index_sid && s->index_start_position > last_index_start) &&
+                (best == -1 ||
+                 s->body_sid <  best_body_sid ||
+                 s->body_sid == best_body_sid && s->index_sid <  best_index_sid ||
+                 s->body_sid == best_body_sid && s->index_sid == best_index_sid && s->index_start_position <  best_index_start ||
+                 s->body_sid == best_body_sid && s->index_sid == best_index_sid && s->index_start_position == best_index_start && s->index_duration > best_index_duration)) {
                 best             = j;
                 best_body_sid    = s->body_sid;
                 best_index_sid   = s->index_sid;
@@ -1341,7 +1348,10 @@ static int mxf_get_sorted_table_segments(MXFContext *mxf, int *nb_sorted_segment
 static int mxf_absolute_bodysid_offset(MXFContext *mxf, int body_sid, int64_t offset, int64_t *offset_out)
 {
     int x;
-    int64_t offset_in = offset;     /* for logging */
+    MXFPartition *last_p = NULL;
+
+    if (offset < 0)
+        return AVERROR(EINVAL);
 
     for (x = 0; x < mxf->partitions_count; x++) {
         MXFPartition *p = &mxf->partitions[x];
@@ -1349,17 +1359,20 @@ static int mxf_absolute_bodysid_offset(MXFContext *mxf, int body_sid, int64_t of
         if (p->body_sid != body_sid)
             continue;
 
-        if (offset < p->essence_length || !p->essence_length) {
-            *offset_out = p->essence_offset + offset;
-            return 0;
-        }
+        if (p->body_offset > offset)
+            break;
+
+        last_p = p;
+    }
 
-        offset -= p->essence_length;
+    if (last_p && (!last_p->essence_length || last_p->essence_length > (offset - last_p->body_offset))) {
+        *offset_out = last_p->essence_offset + (offset - last_p->body_offset);
+        return 0;
     }
 
     av_log(mxf->fc, AV_LOG_ERROR,
            "failed to find absolute offset of %"PRIX64" in BodySID %i - partial file?\n",
-           offset_in, body_sid);
+           offset, body_sid);
 
     return AVERROR_INVALIDDATA;
 }
@@ -1558,14 +1571,6 @@ static int mxf_compute_index_tables(MXFContext *mxf)
 {
     int i, j, k, ret, nb_sorted_segments;
     MXFIndexTableSegment **sorted_segments = NULL;
-    AVStream *st = NULL;
-
-    for (i = 0; i < mxf->fc->nb_streams; i++) {
-        if (mxf->fc->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_DATA)
-            continue;
-        st = mxf->fc->streams[i];
-        break;
-    }
 
     if ((ret = mxf_get_sorted_table_segments(mxf, &nb_sorted_segments, &sorted_segments)) ||
         nb_sorted_segments <= 0) {
@@ -1604,6 +1609,7 @@ static int mxf_compute_index_tables(MXFContext *mxf)
 
     for (i = j = 0; j < mxf->nb_index_tables; i += mxf->index_tables[j++].nb_segments) {
         MXFIndexTable *t = &mxf->index_tables[j];
+        MXFTrack *mxf_track = NULL;
 
         t->segments = av_mallocz_array(t->nb_segments,
                                        sizeof(*t->segments));
@@ -1626,6 +1632,14 @@ static int mxf_compute_index_tables(MXFContext *mxf)
         if ((ret = mxf_compute_ptses_fake_index(mxf, t)) < 0)
             goto finish_decoding_index;
 
+        for (k = 0; k < mxf->fc->nb_streams; k++) {
+            MXFTrack *track = mxf->fc->streams[k]->priv_data;
+            if (track && track->index_sid == t->index_sid) {
+                mxf_track = track;
+                break;
+            }
+        }
+
         /* fix zero IndexDurations */
         for (k = 0; k < t->nb_segments; k++) {
             if (t->segments[k]->index_duration)
@@ -1635,7 +1649,7 @@ static int mxf_compute_index_tables(MXFContext *mxf)
                 av_log(mxf->fc, AV_LOG_WARNING, "IndexSID %i segment %i has zero IndexDuration and there's more than one segment\n",
                        t->index_sid, k);
 
-            if (!st) {
+            if (!mxf_track) {
                 av_log(mxf->fc, AV_LOG_WARNING, "no streams?\n");
                 break;
             }
@@ -1643,7 +1657,7 @@ static int mxf_compute_index_tables(MXFContext *mxf)
             /* assume the first stream's duration is reasonable
              * leave index_duration = 0 on further segments in case we have any (unlikely)
              */
-            t->segments[k]->index_duration = st->duration;
+            t->segments[k]->index_duration = mxf_track->original_duration;
             break;
         }
     }
@@ -3041,6 +3055,42 @@ fail:
     return ret;
 }
 
+static MXFIndexTable *mxf_find_index_table(MXFContext *mxf, int index_sid)
+{
+    int i;
+    for (i = 0; i < mxf->nb_index_tables; i++)
+        if (mxf->index_tables[i].index_sid == index_sid)
+            return &mxf->index_tables[i];
+    return NULL;
+}
+
+/* Get the edit unit of the next packet from current_offset in a track. The returned edit unit can be original_duration as well! */
+static int mxf_get_next_track_edit_unit(MXFContext *mxf, MXFTrack *track, int64_t current_offset, int64_t *edit_unit_out)
+{
+    int64_t a, b, m, offset;
+    MXFIndexTable *t = mxf_find_index_table(mxf, track->index_sid);
+
+    if (!t || track->original_duration <= 0)
+        return -1;
+
+    a = -1;
+    b = track->original_duration;
+
+    while (b - a > 1) {
+        m = (a + b) >> 1;
+        if (mxf_edit_unit_absolute_offset(mxf, t, m, NULL, &offset, 0) < 0)
+            return -1;
+        if (offset < current_offset)
+            a = m;
+        else
+            b = m;
+    }
+
+    *edit_unit_out = b;
+
+    return 0;
+}
+
 /**
  * Sets mxf->current_edit_unit based on what offset we're currently at.
  * @return next_ofs if OK, <0 on error
@@ -3401,6 +3451,20 @@ static int mxf_read_seek(AVFormatContext *s, int stream_index, int64_t sample_ti
         mxf->current_edit_unit = sample_time;
     } else {
         t = &mxf->index_tables[0];
+        if (t->index_sid != source_track->index_sid) {
+            /* If the first index table does not belong to the stream, then find a stream which does belong to the index table */
+            for (i = 0; i < s->nb_streams; i++) {
+                MXFTrack *new_source_track = s->streams[i]->priv_data;
+                if (new_source_track && new_source_track->index_sid == t->index_sid) {
+                    sample_time = av_rescale_q(sample_time, new_source_track->edit_rate, source_track->edit_rate);
+                    source_track = new_source_track;
+                    st = s->streams[i];
+                    break;
+                }
+            }
+            if (i == s->nb_streams)
+                return AVERROR_INVALIDDATA;
+        }
 
         /* clamp above zero, else ff_index_search_timestamp() returns negative
          * this also means we allow seeking before the start */
@@ -3440,13 +3504,19 @@ static int mxf_read_seek(AVFormatContext *s, int stream_index, int64_t sample_ti
     for (i = 0; i < s->nb_streams; i++) {
         AVStream *cur_st = s->streams[i];
         MXFTrack *cur_track = cur_st->priv_data;
-        uint64_t current_sample_count = 0;
         if (cur_st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
-            ret = mxf_compute_sample_count(mxf, i, &current_sample_count);
-            if (ret < 0)
-                return ret;
-
-            cur_track->sample_count = current_sample_count;
+            int64_t track_edit_unit;
+            if (st != cur_st && mxf_get_next_track_edit_unit(mxf, cur_track, seekpos, &track_edit_unit) >= 0) {
+                cur_track->sample_count = av_rescale_q(track_edit_unit,
+                                                       av_inv_q(cur_track->edit_rate),
+                                                       cur_st->time_base);
+            } else {
+                uint64_t current_sample_count = 0;
+                ret = mxf_compute_sample_count(mxf, i, &current_sample_count);
+                if (ret < 0)
+                    return ret;
+                cur_track->sample_count = current_sample_count;
+            }
         }
     }
     return 0;