blob: e71a82de96a9e7f1a62bfa2c761956b192ed79d9 [file] [log] [blame]
// Copyright (c) 2012 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 "base/basictypes.h"
#include "cobalt/media/base/audio_timestamp_helper.h"
#include "cobalt/media/base/timestamp_constants.h"
#include "starboard/types.h"
#include "testing/gtest/include/gtest/gtest.h"
namespace cobalt {
namespace media {
namespace {
const int k48kHz = 48000;
} // namespace
static const int kDefaultSampleRate = 44100;
class AudioTimestampHelperTest : public ::testing::Test {
public:
AudioTimestampHelperTest() : helper_(kDefaultSampleRate) {
helper_.SetBaseTimestamp(base::TimeDelta());
}
// Adds frames to the helper and returns the current timestamp in
// microseconds.
int64_t AddFrames(int frames) {
helper_.AddFrames(frames);
return helper_.GetTimestamp().InMicroseconds();
}
int64_t FramesToTarget(int target_in_microseconds) {
return helper_.GetFramesToTarget(
base::TimeDelta::FromMicroseconds(target_in_microseconds));
}
void TestGetFramesToTargetRange(int frame_count, int start, int end) {
for (int i = start; i <= end; ++i) {
EXPECT_EQ(frame_count, FramesToTarget(i)) << " Failure for timestamp "
<< i << " us.";
}
}
protected:
AudioTimestampHelper helper_;
private:
DISALLOW_COPY_AND_ASSIGN(AudioTimestampHelperTest);
};
TEST_F(AudioTimestampHelperTest, FramesToTime) {
// Negative value.
EXPECT_EQ(base::TimeDelta::FromSeconds(-1),
AudioTimestampHelper::FramesToTime(-48000, k48kHz));
// Zero.
EXPECT_EQ(base::TimeDelta::FromMicroseconds(0),
AudioTimestampHelper::FramesToTime(0, k48kHz));
// One frame.
EXPECT_EQ(base::TimeDelta::FromMicroseconds(20),
AudioTimestampHelper::FramesToTime(1, k48kHz));
// Exact value with maximum precision of TimeDelta.
EXPECT_EQ(base::TimeDelta::FromMicroseconds(15625),
AudioTimestampHelper::FramesToTime(750, k48kHz));
// One second.
EXPECT_EQ(base::TimeDelta::FromSeconds(1),
AudioTimestampHelper::FramesToTime(48000, k48kHz));
// Argument and return value exceeding 32 bits.
EXPECT_EQ(base::TimeDelta::FromSeconds(1000000),
AudioTimestampHelper::FramesToTime(48000000000, k48kHz));
}
TEST_F(AudioTimestampHelperTest, TimeToFrames) {
// Negative value.
EXPECT_EQ(-48000, AudioTimestampHelper::TimeToFrames(
base::TimeDelta::FromSeconds(-1), k48kHz));
// Zero.
EXPECT_EQ(0, AudioTimestampHelper::TimeToFrames(
base::TimeDelta::FromMicroseconds(0), k48kHz));
// Any duration less than 21 microseconds will return zero frames at 48 kHz
// because each frame is 20.833 microseconds.
EXPECT_EQ(0, AudioTimestampHelper::TimeToFrames(
base::TimeDelta::FromMicroseconds(20), k48kHz));
EXPECT_EQ(1, AudioTimestampHelper::TimeToFrames(
base::TimeDelta::FromMicroseconds(21), k48kHz));
// Exact value with maximum precision of TimeDelta.
EXPECT_EQ(750, AudioTimestampHelper::TimeToFrames(
base::TimeDelta::FromMicroseconds(15625), k48kHz));
// One second.
EXPECT_EQ(48000, AudioTimestampHelper::TimeToFrames(
base::TimeDelta::FromSeconds(1), k48kHz));
// Argument and return value exceeding 32 bits.
EXPECT_EQ(48000000000, AudioTimestampHelper::TimeToFrames(
base::TimeDelta::FromSeconds(1000000), k48kHz));
}
TEST_F(AudioTimestampHelperTest, Basic) {
EXPECT_EQ(0, helper_.GetTimestamp().InMicroseconds());
// Verify that the output timestamp is always rounded down to the
// nearest microsecond. 1 frame @ 44100 is ~22.67573 microseconds,
// which is why the timestamp sometimes increments by 23 microseconds
// and other times it increments by 22 microseconds.
EXPECT_EQ(0, AddFrames(0));
EXPECT_EQ(22, AddFrames(1));
EXPECT_EQ(45, AddFrames(1));
EXPECT_EQ(68, AddFrames(1));
EXPECT_EQ(90, AddFrames(1));
EXPECT_EQ(113, AddFrames(1));
// Verify that adding frames one frame at a time matches the timestamp
// returned if the same number of frames are added all at once.
base::TimeDelta timestamp_1 = helper_.GetTimestamp();
helper_.SetBaseTimestamp(kNoTimestamp);
EXPECT_TRUE(kNoTimestamp == helper_.base_timestamp());
helper_.SetBaseTimestamp(base::TimeDelta());
EXPECT_EQ(0, helper_.GetTimestamp().InMicroseconds());
helper_.AddFrames(5);
EXPECT_EQ(113, helper_.GetTimestamp().InMicroseconds());
EXPECT_TRUE(timestamp_1 == helper_.GetTimestamp());
}
TEST_F(AudioTimestampHelperTest, GetDuration) {
helper_.SetBaseTimestamp(base::TimeDelta::FromMicroseconds(100));
int frame_count = 5;
int64_t expected_durations[] = {113, 113, 114, 113, 113, 114};
for (size_t i = 0; i < arraysize(expected_durations); ++i) {
base::TimeDelta duration = helper_.GetFrameDuration(frame_count);
EXPECT_EQ(expected_durations[i], duration.InMicroseconds());
base::TimeDelta timestamp_1 = helper_.GetTimestamp() + duration;
helper_.AddFrames(frame_count);
base::TimeDelta timestamp_2 = helper_.GetTimestamp();
EXPECT_TRUE(timestamp_1 == timestamp_2);
}
}
TEST_F(AudioTimestampHelperTest, GetFramesToTarget) {
// Verify GetFramesToTarget() rounding behavior.
// 1 frame @ 44100 is ~22.67573 microseconds,
// Test values less than half of the frame duration.
TestGetFramesToTargetRange(0, 0, 11);
// Test values between half the frame duration & the
// full frame duration.
TestGetFramesToTargetRange(1, 12, 22);
// Verify that the same number of frames is returned up
// to the next half a frame.
TestGetFramesToTargetRange(1, 23, 34);
// Verify the next 3 ranges.
TestGetFramesToTargetRange(2, 35, 56);
TestGetFramesToTargetRange(3, 57, 79);
TestGetFramesToTargetRange(4, 80, 102);
TestGetFramesToTargetRange(5, 103, 124);
// Add frames to the helper so negative frame counts can be tested.
helper_.AddFrames(5);
// Note: The timestamp ranges must match the positive values
// tested above to verify that the code is rounding properly.
TestGetFramesToTargetRange(0, 103, 124);
TestGetFramesToTargetRange(-1, 80, 102);
TestGetFramesToTargetRange(-2, 57, 79);
TestGetFramesToTargetRange(-3, 35, 56);
TestGetFramesToTargetRange(-4, 12, 34);
TestGetFramesToTargetRange(-5, 0, 11);
}
} // namespace media
} // namespace cobalt