1 /*
2  *  Copyright (c) 2019 The WebRTC project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 
11 #include "modules/video_coding/unique_timestamp_counter.h"
12 
13 #include <cstdint>
14 #include <memory>
15 #include <set>
16 
17 namespace webrtc {
18 namespace {
19 
20 constexpr int kMaxHistory = 1000;
21 
22 }  // namespace
23 
UniqueTimestampCounter()24 UniqueTimestampCounter::UniqueTimestampCounter()
25     : latest_(std::make_unique<uint32_t[]>(kMaxHistory)) {}
26 
Add(uint32_t value)27 void UniqueTimestampCounter::Add(uint32_t value) {
28   if (value == last_ || !search_index_.insert(value).second) {
29     // Already known.
30     return;
31   }
32   int index = unique_seen_ % kMaxHistory;
33   if (unique_seen_ >= kMaxHistory) {
34     search_index_.erase(latest_[index]);
35   }
36   latest_[index] = value;
37   last_ = value;
38   ++unique_seen_;
39 }
40 
41 }  // namespace webrtc
42