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/utility/decoded_frames_history.h"
12
13 #include <algorithm>
14
15 #include "rtc_base/checks.h"
16 #include "rtc_base/logging.h"
17
18 namespace webrtc {
19 namespace video_coding {
20
DecodedFramesHistory(size_t window_size)21 DecodedFramesHistory::DecodedFramesHistory(size_t window_size)
22 : buffer_(window_size) {}
23
24 DecodedFramesHistory::~DecodedFramesHistory() = default;
25
InsertDecoded(int64_t frame_id,uint32_t timestamp)26 void DecodedFramesHistory::InsertDecoded(int64_t frame_id, uint32_t timestamp) {
27 last_decoded_frame_ = frame_id;
28 last_decoded_frame_timestamp_ = timestamp;
29 int new_index = FrameIdToIndex(frame_id);
30
31 RTC_DCHECK(last_frame_id_ < frame_id);
32
33 // Clears expired values from the cyclic buffer_.
34 if (last_frame_id_) {
35 int64_t id_jump = frame_id - *last_frame_id_;
36 int last_index = FrameIdToIndex(*last_frame_id_);
37
38 if (id_jump >= static_cast<int64_t>(buffer_.size())) {
39 std::fill(buffer_.begin(), buffer_.end(), false);
40 } else if (new_index > last_index) {
41 std::fill(buffer_.begin() + last_index + 1, buffer_.begin() + new_index,
42 false);
43 } else {
44 std::fill(buffer_.begin() + last_index + 1, buffer_.end(), false);
45 std::fill(buffer_.begin(), buffer_.begin() + new_index, false);
46 }
47 }
48
49 buffer_[new_index] = true;
50 last_frame_id_ = frame_id;
51 }
52
WasDecoded(int64_t frame_id) const53 bool DecodedFramesHistory::WasDecoded(int64_t frame_id) const {
54 if (!last_frame_id_)
55 return false;
56
57 // Reference to the picture_id out of the stored should happen.
58 if (frame_id <= *last_frame_id_ - static_cast<int64_t>(buffer_.size())) {
59 RTC_LOG(LS_WARNING) << "Referencing a frame out of the window. "
60 "Assuming it was undecoded to avoid artifacts.";
61 return false;
62 }
63
64 if (frame_id > last_frame_id_)
65 return false;
66
67 return buffer_[FrameIdToIndex(frame_id)];
68 }
69
Clear()70 void DecodedFramesHistory::Clear() {
71 last_decoded_frame_timestamp_.reset();
72 last_decoded_frame_.reset();
73 std::fill(buffer_.begin(), buffer_.end(), false);
74 last_frame_id_.reset();
75 }
76
GetLastDecodedFrameId() const77 absl::optional<int64_t> DecodedFramesHistory::GetLastDecodedFrameId() const {
78 return last_decoded_frame_;
79 }
80
GetLastDecodedFrameTimestamp() const81 absl::optional<uint32_t> DecodedFramesHistory::GetLastDecodedFrameTimestamp()
82 const {
83 return last_decoded_frame_timestamp_;
84 }
85
FrameIdToIndex(int64_t frame_id) const86 int DecodedFramesHistory::FrameIdToIndex(int64_t frame_id) const {
87 int m = frame_id % buffer_.size();
88 return m >= 0 ? m : m + buffer_.size();
89 }
90
91 } // namespace video_coding
92 } // namespace webrtc
93