shaka-packager/media/mp4/chunk_info_iterator.h

70 lines
2.1 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
//
// Implements a wrapper around Sample to Chunk Box (STSC) to iterate through
// the compressed table by sample/chunk. This class also provides a convenient
// function to query total number of samples from start_chunk to end_chunk.
#ifndef MEDIA_MP4_CHUNK_INFO_ITERATOR_H_
#define MEDIA_MP4_CHUNK_INFO_ITERATOR_H_
#include <vector>
#include "media/mp4/box_definitions.h"
namespace media {
namespace mp4 {
class ChunkInfoIterator {
public:
explicit ChunkInfoIterator(const SampleToChunk& sample_to_chunk);
// Advance the properties to refer to the next chunk. Return status
// indicating whether the chunk is still valid.
bool AdvanceChunk();
// Advance the properties to refer to the next sample. Return status
// indicating whether the sample is still valid.
bool AdvanceSample();
// Return whether the current chunk is valid.
bool IsValid() const;
// Return current chunk.
uint32 current_chunk() const { return current_chunk_; }
// Return samples per chunk for current chunk.
uint32 samples_per_chunk() const { return iterator_->samples_per_chunk; }
// Return sample description index for current chunk.
uint32 sample_description_index() const {
return iterator_->sample_description_index;
}
// Return number of samples from start_chunk to end_chunk, both 1-based,
// inclusive.
uint32 NumSamples(uint32 start_chunk, uint32 end_chunk) const;
// Return the last first_chunk in chunk_info_table.
uint32 LastFirstChunk() const {
return chunk_info_table_.empty() ? 0
: chunk_info_table_.back().first_chunk;
}
private:
uint32 chunk_sample_index_;
uint32 current_chunk_;
const std::vector<ChunkInfo>& chunk_info_table_;
std::vector<ChunkInfo>::const_iterator iterator_;
DISALLOW_COPY_AND_ASSIGN(ChunkInfoIterator);
};
} // namespace mp4
} // namespace media
#endif // MEDIA_MP4_CHUNK_INFO_ITERATOR_H_