1 /*
2 * Copyright (c) 2020 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 #include "modules/video_coding/frame_dependencies_calculator.h"
11
12 #include <stdint.h>
13
14 #include <iterator>
15 #include <set>
16
17 #include "absl/algorithm/container.h"
18 #include "absl/container/inlined_vector.h"
19 #include "api/array_view.h"
20 #include "api/video/video_frame_type.h"
21 #include "rtc_base/checks.h"
22 #include "rtc_base/logging.h"
23
24 namespace webrtc {
25
FromBuffersUsage(VideoFrameType frame_type,int64_t frame_id,rtc::ArrayView<const CodecBufferUsage> buffers_usage)26 absl::InlinedVector<int64_t, 5> FrameDependenciesCalculator::FromBuffersUsage(
27 VideoFrameType frame_type,
28 int64_t frame_id,
29 rtc::ArrayView<const CodecBufferUsage> buffers_usage) {
30 absl::InlinedVector<int64_t, 5> dependencies;
31 RTC_DCHECK_GT(buffers_usage.size(), 0);
32 for (const CodecBufferUsage& buffer_usage : buffers_usage) {
33 RTC_CHECK_GE(buffer_usage.id, 0);
34 if (buffers_.size() <= static_cast<size_t>(buffer_usage.id)) {
35 buffers_.resize(buffer_usage.id + 1);
36 }
37 }
38 std::set<int64_t> direct_depenendencies;
39 std::set<int64_t> indirect_depenendencies;
40 if (frame_type == VideoFrameType::kVideoFrameDelta) {
41 for (const CodecBufferUsage& buffer_usage : buffers_usage) {
42 if (!buffer_usage.referenced) {
43 continue;
44 }
45 const BufferUsage& buffer = buffers_[buffer_usage.id];
46 if (buffer.frame_id == absl::nullopt) {
47 RTC_LOG(LS_ERROR) << "Odd configuration: frame " << frame_id
48 << " references buffer #" << buffer_usage.id
49 << " that was never updated.";
50 continue;
51 }
52 direct_depenendencies.insert(*buffer.frame_id);
53 indirect_depenendencies.insert(buffer.dependencies.begin(),
54 buffer.dependencies.end());
55 }
56 // Reduce references: if frame #3 depends on frame #2 and #1, and frame #2
57 // depends on frame #1, then frame #3 needs to depend just on frame #2.
58 // Though this set diff removes only 1 level of indirection, it seems
59 // enough for all currently used structures.
60 absl::c_set_difference(direct_depenendencies, indirect_depenendencies,
61 std::back_inserter(dependencies));
62 }
63
64 // Update buffers.
65 for (const CodecBufferUsage& buffer_usage : buffers_usage) {
66 if (!buffer_usage.updated) {
67 continue;
68 }
69 BufferUsage& buffer = buffers_[buffer_usage.id];
70 buffer.frame_id = frame_id;
71 buffer.dependencies.assign(direct_depenendencies.begin(),
72 direct_depenendencies.end());
73 }
74
75 return dependencies;
76 }
77
78 } // namespace webrtc
79