1 /*
2 * Copyright (c) 2018 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/framerate_controller.h"
12
13 #include <stddef.h>
14
15 #include "test/gtest.h"
16
17 namespace webrtc {
18
TEST(FramerateController,KeepTargetFramerate)19 TEST(FramerateController, KeepTargetFramerate) {
20 const float input_framerate_fps = 20;
21 const float target_framerate_fps = 5;
22 const float max_abs_framerate_error_fps = target_framerate_fps * 0.1f;
23 const size_t input_duration_secs = 3;
24 const size_t num_input_frames = input_duration_secs * input_framerate_fps;
25
26 FramerateController framerate_controller(target_framerate_fps);
27 size_t num_dropped_frames = 0;
28 for (size_t frame_num = 0; frame_num < num_input_frames; ++frame_num) {
29 const uint32_t timestamp_ms =
30 static_cast<uint32_t>(1000 * frame_num / input_framerate_fps);
31 if (framerate_controller.DropFrame(timestamp_ms)) {
32 ++num_dropped_frames;
33 } else {
34 framerate_controller.AddFrame(timestamp_ms);
35 }
36 }
37
38 const float output_framerate_fps =
39 static_cast<float>(num_input_frames - num_dropped_frames) /
40 input_duration_secs;
41 EXPECT_NEAR(output_framerate_fps, target_framerate_fps,
42 max_abs_framerate_error_fps);
43 }
44
TEST(FramerateController,DoNotDropAnyFramesIfTargerEqualsInput)45 TEST(FramerateController, DoNotDropAnyFramesIfTargerEqualsInput) {
46 const float input_framerate_fps = 30;
47 const size_t input_duration_secs = 3;
48 const size_t num_input_frames = input_duration_secs * input_framerate_fps;
49
50 FramerateController framerate_controller(input_framerate_fps);
51 size_t num_dropped_frames = 0;
52 for (size_t frame_num = 0; frame_num < num_input_frames; ++frame_num) {
53 const uint32_t timestamp_ms =
54 static_cast<uint32_t>(1000 * frame_num / input_framerate_fps);
55 if (framerate_controller.DropFrame(timestamp_ms)) {
56 ++num_dropped_frames;
57 } else {
58 framerate_controller.AddFrame(timestamp_ms);
59 }
60 }
61
62 EXPECT_EQ(num_dropped_frames, 0U);
63 }
64
TEST(FramerateController,DoNotDropFrameWhenTimestampJumpsBackward)65 TEST(FramerateController, DoNotDropFrameWhenTimestampJumpsBackward) {
66 FramerateController framerate_controller(30);
67 ASSERT_FALSE(framerate_controller.DropFrame(66));
68 framerate_controller.AddFrame(66);
69 EXPECT_FALSE(framerate_controller.DropFrame(33));
70 }
71
TEST(FramerateController,DropFrameIfItIsTooCloseToPreviousFrame)72 TEST(FramerateController, DropFrameIfItIsTooCloseToPreviousFrame) {
73 FramerateController framerate_controller(30);
74 ASSERT_FALSE(framerate_controller.DropFrame(33));
75 framerate_controller.AddFrame(33);
76 EXPECT_TRUE(framerate_controller.DropFrame(34));
77 }
78
TEST(FramerateController,FrameDroppingStartsFromSecondInputFrame)79 TEST(FramerateController, FrameDroppingStartsFromSecondInputFrame) {
80 const float input_framerate_fps = 23;
81 const float target_framerate_fps = 19;
82 const uint32_t input_frame_duration_ms =
83 static_cast<uint32_t>(1000 / input_framerate_fps);
84 FramerateController framerate_controller(target_framerate_fps);
85 ASSERT_FALSE(framerate_controller.DropFrame(1 * input_frame_duration_ms));
86 framerate_controller.AddFrame(1 * input_frame_duration_ms);
87 EXPECT_TRUE(framerate_controller.DropFrame(2 * input_frame_duration_ms));
88 }
89
90 } // namespace webrtc
91