shaka-packager/media/mp4/composition_offset_iterator.h

56 lines
1.7 KiB
C++

// Copyright 2014 Google Inc. All rights reserved.
//
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file or at
// https://developers.google.com/open-source/licenses/bsd
#ifndef MEDIA_MP4_COMPOSITION_OFFSET_ITERATOR_H_
#define MEDIA_MP4_COMPOSITION_OFFSET_ITERATOR_H_
#include <vector>
#include "media/mp4/box_definitions.h"
namespace media {
namespace mp4 {
/// Composition time to sample box (CTTS) iterator used to iterate through the
/// compressed table. This class also provides convenient functions to query
/// total number of samples and the composition offset for a particular sample.
class CompositionOffsetIterator {
public:
/// Create CompositionOffsetIterator from composition time to sample box.
explicit CompositionOffsetIterator(
const CompositionTimeToSample& composition_time_to_sample);
~CompositionOffsetIterator();
/// Advance the iterator to the next sample.
/// @return true if not past the last sample, false otherwise.
bool AdvanceSample();
/// @return true if the iterator is still valid, false if past the last
/// sample.
bool IsValid() const;
/// @return Sample offset for current sample.
uint32 sample_offset() const { return iterator_->sample_offset; }
/// @return Sample offset @a sample, 1-based.
uint32 SampleOffset(uint32 sample) const;
/// @return Total number of samples.
uint32 NumSamples() const;
private:
uint32 sample_index_;
const std::vector<CompositionOffset>& composition_offset_table_;
std::vector<CompositionOffset>::const_iterator iterator_;
DISALLOW_COPY_AND_ASSIGN(CompositionOffsetIterator);
};
} // namespace mp4
} // namespace media
#endif // MEDIA_MP4_COMPOSITION_OFFSET_ITERATOR_H_