From: Tomas Härdin <[email protected]>

Such files have IndexTableSegments which when parsed cover EditUnit ranges
like this:

 [0,1)
 [249,250)
 [249,377)
 [0,249)

where each interval is

 [IndexStartPosition, IndexStartPosition + IndexDuration)

This would be reduced to a sparse index like:

 [0,1), [249,250)

instead of the full range:

 [0,249), [249,377)

Sample: http://streams.videolan.org/issues/7302/TimeCode_HD.mxf
Signed-off-by: Luca Barbato <[email protected]>
---
 libavformat/mxfdec.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/libavformat/mxfdec.c b/libavformat/mxfdec.c
index 7bca23d..2fc31bf 100644
--- a/libavformat/mxfdec.c
+++ b/libavformat/mxfdec.c
@@ -980,19 +980,23 @@ static int mxf_get_sorted_table_segments(MXFContext *mxf, 
int *nb_sorted_segment
     /* sort segments by {BodySID, IndexSID, IndexStartPosition}, remove 
duplicates while we're at it */
     for (i = 0; i < nb_segments; i++) {
         int best = -1, best_body_sid = -1, best_index_sid = -1, 
best_index_start = -1;
+        uint64_t best_index_duration = 0;
 
         for (j = 0; j < nb_segments; j++) {
             MXFIndexTableSegment *s = unsorted_segments[j];
 
             /* Require larger BosySID, IndexSID or IndexStartPosition then the 
previous entry. This removes duplicates.
              * 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)) {
+                (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))) {
                 best             = j;
                 best_body_sid    = s->body_sid;
                 best_index_sid   = s->index_sid;
                 best_index_start = s->index_start_position;
+                best_index_duration = s->index_duration;
             }
         }
 
-- 
1.8.5.1

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