1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
|
// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <gtest/gtest.h>
#include <stdint.h>
#include "base/macros.h"
#include "base/test/simple_test_tick_clock.h"
#include "base/time/time.h"
#include "media/cast/constants.h"
#include "media/cast/net/rtp/receiver_stats.h"
#include "media/cast/net/rtp/rtp_defines.h"
namespace media {
namespace cast {
static const int64_t kStartMillisecond = INT64_C(12345678900000);
static const uint32_t kStdTimeIncrementMs = 33;
class ReceiverStatsTest : public ::testing::Test {
protected:
ReceiverStatsTest()
: stats_(&testing_clock_) {
testing_clock_.Advance(
base::TimeDelta::FromMilliseconds(kStartMillisecond));
start_time_ = testing_clock_.NowTicks();
delta_increments_ = base::TimeDelta::FromMilliseconds(kStdTimeIncrementMs);
}
~ReceiverStatsTest() override = default;
uint32_t ExpectedJitter(uint32_t const_interval, int num_packets) {
float jitter = 0;
// Assume timestamps have a constant kStdTimeIncrementMs interval.
float float_interval =
static_cast<float>(const_interval - kStdTimeIncrementMs);
for (int i = 0; i < num_packets; ++i) {
jitter += (float_interval - jitter) / 16;
}
return static_cast<uint32_t>(jitter + 0.5f);
}
ReceiverStats stats_;
RtpCastHeader rtp_header_;
base::SimpleTestTickClock testing_clock_;
base::TimeTicks start_time_;
base::TimeDelta delta_increments_;
private:
DISALLOW_COPY_AND_ASSIGN(ReceiverStatsTest);
};
TEST_F(ReceiverStatsTest, ResetState) {
RtpReceiverStatistics s = stats_.GetStatistics();
EXPECT_EQ(0u, s.fraction_lost);
EXPECT_EQ(0u, s.cumulative_lost);
EXPECT_EQ(0u, s.extended_high_sequence_number);
EXPECT_EQ(0u, s.jitter);
}
TEST_F(ReceiverStatsTest, LossCount) {
for (int i = 0; i < 300; ++i) {
if (i % 4)
stats_.UpdateStatistics(rtp_header_, kVideoFrequency);
if (i % 3) {
rtp_header_.rtp_timestamp += RtpTimeDelta::FromTimeDelta(
base::TimeDelta::FromMilliseconds(33), kVideoFrequency);
}
++rtp_header_.sequence_number;
testing_clock_.Advance(delta_increments_);
}
RtpReceiverStatistics s = stats_.GetStatistics();
EXPECT_EQ(63u, s.fraction_lost);
EXPECT_EQ(74u, s.cumulative_lost);
// Build extended sequence number.
const uint32_t extended_seq_num = rtp_header_.sequence_number - 1;
EXPECT_EQ(extended_seq_num, s.extended_high_sequence_number);
}
TEST_F(ReceiverStatsTest, NoLossWrap) {
rtp_header_.sequence_number = 65500;
for (int i = 0; i < 300; ++i) {
stats_.UpdateStatistics(rtp_header_, kVideoFrequency);
if (i % 3) {
rtp_header_.rtp_timestamp += RtpTimeDelta::FromTimeDelta(
base::TimeDelta::FromMilliseconds(33), kVideoFrequency);
}
++rtp_header_.sequence_number;
testing_clock_.Advance(delta_increments_);
}
RtpReceiverStatistics s = stats_.GetStatistics();
EXPECT_EQ(0u, s.fraction_lost);
EXPECT_EQ(0u, s.cumulative_lost);
// Build extended sequence number (one wrap cycle).
const uint32_t extended_seq_num = (1 << 16) + rtp_header_.sequence_number - 1;
EXPECT_EQ(extended_seq_num, s.extended_high_sequence_number);
}
TEST_F(ReceiverStatsTest, LossCountWrap) {
const uint32_t kStartSequenceNumber = 65500;
rtp_header_.sequence_number = kStartSequenceNumber;
for (int i = 0; i < 300; ++i) {
if (i % 4)
stats_.UpdateStatistics(rtp_header_, kVideoFrequency);
if (i % 3)
rtp_header_.rtp_timestamp += RtpTimeDelta::FromTicks(1);
++rtp_header_.sequence_number;
testing_clock_.Advance(delta_increments_);
}
RtpReceiverStatistics s = stats_.GetStatistics();
EXPECT_EQ(63u, s.fraction_lost);
EXPECT_EQ(74u, s.cumulative_lost);
// Build extended sequence number (one wrap cycle).
const uint32_t extended_seq_num = (1 << 16) + rtp_header_.sequence_number - 1;
EXPECT_EQ(extended_seq_num, s.extended_high_sequence_number);
}
TEST_F(ReceiverStatsTest, BasicJitter) {
for (int i = 0; i < 300; ++i) {
stats_.UpdateStatistics(rtp_header_, kVideoFrequency);
++rtp_header_.sequence_number;
rtp_header_.rtp_timestamp += RtpTimeDelta::FromTimeDelta(
base::TimeDelta::FromMilliseconds(33), kVideoFrequency);
testing_clock_.Advance(delta_increments_);
}
RtpReceiverStatistics s = stats_.GetStatistics();
EXPECT_FALSE(s.fraction_lost);
EXPECT_FALSE(s.cumulative_lost);
// Build extended sequence number (one wrap cycle).
const uint32_t extended_seq_num = rtp_header_.sequence_number - 1;
EXPECT_EQ(extended_seq_num, s.extended_high_sequence_number);
EXPECT_EQ(ExpectedJitter(kStdTimeIncrementMs, 300), s.jitter);
}
TEST_F(ReceiverStatsTest, NonTrivialJitter) {
const int kAdditionalIncrement = 5;
for (int i = 0; i < 300; ++i) {
stats_.UpdateStatistics(rtp_header_, kVideoFrequency);
++rtp_header_.sequence_number;
rtp_header_.rtp_timestamp += RtpTimeDelta::FromTimeDelta(
base::TimeDelta::FromMilliseconds(33), kVideoFrequency);
base::TimeDelta additional_delta =
base::TimeDelta::FromMilliseconds(kAdditionalIncrement);
testing_clock_.Advance(delta_increments_ + additional_delta);
}
RtpReceiverStatistics s = stats_.GetStatistics();
EXPECT_FALSE(s.fraction_lost);
EXPECT_FALSE(s.cumulative_lost);
// Build extended sequence number (one wrap cycle).
const uint32_t extended_seq_num = rtp_header_.sequence_number - 1;
EXPECT_EQ(extended_seq_num, s.extended_high_sequence_number);
EXPECT_EQ(ExpectedJitter(kStdTimeIncrementMs + kAdditionalIncrement, 300),
s.jitter);
}
} // namespace cast
} // namespace media
|
