1 // Copyright 2014 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #include "media/formats/mp4/sample_to_group_iterator.h" 6 7 #include "base/logging.h" 8 9 namespace media { 10 namespace mp4 { 11 12 SampleToGroupIterator::SampleToGroupIterator( 13 const SampleToGroup& sample_to_group) 14 : remaining_samples_(0), 15 sample_to_group_table_(sample_to_group.entries), 16 iterator_(sample_to_group_table_.begin()) { 17 // Handle the case that the table contains an entry with sample count 0. 18 while (iterator_ != sample_to_group_table_.end()) { 19 remaining_samples_ = iterator_->sample_count; 20 if (remaining_samples_ > 0) 21 break; 22 ++iterator_; 23 } 24 } 25 26 SampleToGroupIterator::~SampleToGroupIterator() {} 27 28 bool SampleToGroupIterator::Advance() { 29 DCHECK(IsValid()); 30 31 --remaining_samples_; 32 // Handle the case that the table contains an entry with sample count 0. 33 while (remaining_samples_ == 0) { 34 ++iterator_; 35 if (iterator_ == sample_to_group_table_.end()) 36 return false; 37 remaining_samples_ = iterator_->sample_count; 38 } 39 return true; 40 } 41 42 bool SampleToGroupIterator::IsValid() const { 43 return remaining_samples_ > 0; 44 } 45 46 } // namespace mp4 47 } // namespace media 48
