xref: /aosp_15_r20/external/webrtc/video/unique_timestamp_counter.cc (revision d9f758449e529ab9291ac668be2861e7a55c2422)
1*d9f75844SAndroid Build Coastguard Worker /*
2*d9f75844SAndroid Build Coastguard Worker  *  Copyright (c) 2019 The WebRTC project authors. All Rights Reserved.
3*d9f75844SAndroid Build Coastguard Worker  *
4*d9f75844SAndroid Build Coastguard Worker  *  Use of this source code is governed by a BSD-style license
5*d9f75844SAndroid Build Coastguard Worker  *  that can be found in the LICENSE file in the root of the source
6*d9f75844SAndroid Build Coastguard Worker  *  tree. An additional intellectual property rights grant can be found
7*d9f75844SAndroid Build Coastguard Worker  *  in the file PATENTS.  All contributing project authors may
8*d9f75844SAndroid Build Coastguard Worker  *  be found in the AUTHORS file in the root of the source tree.
9*d9f75844SAndroid Build Coastguard Worker  */
10*d9f75844SAndroid Build Coastguard Worker 
11*d9f75844SAndroid Build Coastguard Worker #include "video/unique_timestamp_counter.h"
12*d9f75844SAndroid Build Coastguard Worker 
13*d9f75844SAndroid Build Coastguard Worker #include <cstdint>
14*d9f75844SAndroid Build Coastguard Worker #include <memory>
15*d9f75844SAndroid Build Coastguard Worker #include <set>
16*d9f75844SAndroid Build Coastguard Worker 
17*d9f75844SAndroid Build Coastguard Worker namespace webrtc {
18*d9f75844SAndroid Build Coastguard Worker namespace {
19*d9f75844SAndroid Build Coastguard Worker 
20*d9f75844SAndroid Build Coastguard Worker constexpr int kMaxHistory = 1000;
21*d9f75844SAndroid Build Coastguard Worker 
22*d9f75844SAndroid Build Coastguard Worker }  // namespace
23*d9f75844SAndroid Build Coastguard Worker 
UniqueTimestampCounter()24*d9f75844SAndroid Build Coastguard Worker UniqueTimestampCounter::UniqueTimestampCounter()
25*d9f75844SAndroid Build Coastguard Worker     : latest_(std::make_unique<uint32_t[]>(kMaxHistory)) {}
26*d9f75844SAndroid Build Coastguard Worker 
Add(uint32_t value)27*d9f75844SAndroid Build Coastguard Worker void UniqueTimestampCounter::Add(uint32_t value) {
28*d9f75844SAndroid Build Coastguard Worker   if (value == last_ || !search_index_.insert(value).second) {
29*d9f75844SAndroid Build Coastguard Worker     // Already known.
30*d9f75844SAndroid Build Coastguard Worker     return;
31*d9f75844SAndroid Build Coastguard Worker   }
32*d9f75844SAndroid Build Coastguard Worker   int index = unique_seen_ % kMaxHistory;
33*d9f75844SAndroid Build Coastguard Worker   if (unique_seen_ >= kMaxHistory) {
34*d9f75844SAndroid Build Coastguard Worker     search_index_.erase(latest_[index]);
35*d9f75844SAndroid Build Coastguard Worker   }
36*d9f75844SAndroid Build Coastguard Worker   latest_[index] = value;
37*d9f75844SAndroid Build Coastguard Worker   last_ = value;
38*d9f75844SAndroid Build Coastguard Worker   ++unique_seen_;
39*d9f75844SAndroid Build Coastguard Worker }
40*d9f75844SAndroid Build Coastguard Worker 
41*d9f75844SAndroid Build Coastguard Worker }  // namespace webrtc
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