shaka-packager/media/formats/mp4/composition_offset_iterator.cc

64 lines
1.9 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
#include "media/formats/mp4/composition_offset_iterator.h"
#include "base/logging.h"
namespace edash_packager {
namespace media {
namespace mp4 {
CompositionOffsetIterator::CompositionOffsetIterator(
const CompositionTimeToSample& composition_time_to_sample)
: sample_index_(0),
composition_offset_table_(composition_time_to_sample.composition_offset),
iterator_(composition_offset_table_.begin()) {}
CompositionOffsetIterator::~CompositionOffsetIterator() {}
bool CompositionOffsetIterator::AdvanceSample() {
++sample_index_;
if (sample_index_ >= iterator_->sample_count) {
++iterator_;
if (iterator_ == composition_offset_table_.end())
return false;
sample_index_ = 0;
}
return true;
}
bool CompositionOffsetIterator::IsValid() const {
return iterator_ != composition_offset_table_.end() &&
sample_index_ < iterator_->sample_count;
}
int32_t CompositionOffsetIterator::SampleOffset(uint32_t sample) const {
uint32_t current_sample = 0;
std::vector<CompositionOffset>::const_iterator it =
composition_offset_table_.begin();
for (; it != composition_offset_table_.end(); ++it) {
current_sample += it->sample_count;
if (current_sample >= sample)
return it->sample_offset;
}
DCHECK_LE(sample, current_sample) << " Sample is invalid";
return 0;
}
uint32_t CompositionOffsetIterator::NumSamples() const {
uint32_t num_samples = 0;
std::vector<CompositionOffset>::const_iterator it =
composition_offset_table_.begin();
for (; it != composition_offset_table_.end(); ++it) {
num_samples += it->sample_count;
}
return num_samples;
}
} // namespace mp4
} // namespace media
} // namespace edash_packager