webm_file: Implement HasAccurateClusterDuration()
Iterate through all the Clusters and check if Duration is set on
the last frame of each Cluster (except for the last Cluster which
is ignored).
Change-Id: Ifdbdcb9e1d57afbd995d4377fcd6118e947c1540
diff --git a/shared/webm_file.cc b/shared/webm_file.cc
index a2428cb..7fb8db9 100644
--- a/shared/webm_file.cc
+++ b/shared/webm_file.cc
@@ -693,6 +693,45 @@
return true;
}
+bool WebMFile::HasAccurateClusterDuration() const {
+ if (state_ <= kParsingHeader)
+ return false;
+
+ const mkvparser::Cluster* cluster = segment_->GetFirst();
+ map<int64, bool> track_has_duration;
+ // Iterate through all the Clusters and check if the last frame in each of
+ // them has Duration set.
+ while (cluster != NULL && !cluster->EOS()) {
+ // This check is done at the beginning of the loop because we don't care
+ // about the last Cluster.
+ for (map<int64, bool>::const_iterator it = track_has_duration.begin();
+ it != track_has_duration.end(); ++it) {
+ if (!it->second)
+ return false;
+ }
+ track_has_duration.clear();
+ const mkvparser::BlockEntry* block_entry;
+ if (cluster->GetFirst(block_entry))
+ return false;
+
+ while (block_entry != NULL && !block_entry->EOS()) {
+ const int64 track_number = block_entry->GetBlock()->GetTrackNumber();
+ if (block_entry->GetKind() == mkvparser::BlockEntry::kBlockGroup) {
+ const mkvparser::BlockGroup* const block_group =
+ reinterpret_cast<const mkvparser::BlockGroup* const>(block_entry);
+ track_has_duration[track_number] =
+ (block_group->GetDurationTimeCode() > 0);
+ } else {
+ track_has_duration[track_number] = false;
+ }
+ if (cluster->GetNext(block_entry, block_entry))
+ return false;
+ }
+ cluster = segment_->GetNext(cluster);
+ }
+ return true;
+}
+
bool WebMFile::CheckForCues() const {
if (state_ <= kParsingHeader)
return false;
diff --git a/shared/webm_file.h b/shared/webm_file.h
index b8b407c..c2689c2 100644
--- a/shared/webm_file.h
+++ b/shared/webm_file.h
@@ -196,6 +196,12 @@
// output to be valid.
bool CuesFirstInCluster(TrackTypes type) const;
+ // Returns true if the file has accurate cluster duration for all the
+ // Clusters. The last Cluster is not checked. By convention it is still
+ // considered to have accurate cluster duration irrespective of the last
+ // Cluster.
+ bool HasAccurateClusterDuration() const;
+
// Returns the display width of the first video track. Returns 0 if there
// is no video track. Parser state must be >= kParsingClusters for output to
// be valid.
