Revert "Revert part of r7561, "Refactor audio conversion functions.""

This restores the conversion changes to AudioProcessing originally
added in r7561, with minor alterations to ensure it passes all tests.

TBR=kwiberg

Review URL: https://webrtc-codereview.appspot.com/28899004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@7574 4adac7df-926f-26a2-2b94-8c16560cd09d
This commit is contained in:
andrew@webrtc.org 2014-10-31 04:58:14 +00:00
parent 14146e40aa
commit 8328e7c44d
6 changed files with 67 additions and 49 deletions

View File

@ -49,7 +49,7 @@ static inline int16_t FloatS16ToS16(float v) {
}
static inline float FloatToFloatS16(float v) {
return v > 0 ? v * limits_int16::max() : -v * limits_int16::min();
return v * (v > 0 ? limits_int16::max() : -limits_int16::min());
}
static inline float FloatS16ToFloat(float v) {

View File

@ -51,18 +51,11 @@ int KeyboardChannelIndex(AudioProcessing::ChannelLayout layout) {
return -1;
}
void StereoToMono(const float* left, const float* right, float* out,
template <typename T>
void StereoToMono(const T* left, const T* right, T* out,
int samples_per_channel) {
for (int i = 0; i < samples_per_channel; ++i) {
for (int i = 0; i < samples_per_channel; ++i)
out[i] = (left[i] + right[i]) / 2;
}
}
void StereoToMono(const int16_t* left, const int16_t* right, int16_t* out,
int samples_per_channel) {
for (int i = 0; i < samples_per_channel; ++i) {
out[i] = (left[i] + right[i]) >> 1;
}
}
} // namespace
@ -114,13 +107,7 @@ class IFChannelBuffer {
void RefreshI() {
if (!ivalid_) {
assert(fvalid_);
const float* const float_data = fbuf_.data();
int16_t* const int_data = ibuf_.data();
const int length = ibuf_.length();
for (int i = 0; i < length; ++i)
int_data[i] = WEBRTC_SPL_SAT(std::numeric_limits<int16_t>::max(),
float_data[i],
std::numeric_limits<int16_t>::min());
FloatS16ToS16(fbuf_.data(), ibuf_.length(), ibuf_.data());
ivalid_ = true;
}
}
@ -228,10 +215,10 @@ void AudioBuffer::CopyFrom(const float* const* data,
data_ptr = process_buffer_->channels();
}
// Convert to int16.
// Convert to the S16 range.
for (int i = 0; i < num_proc_channels_; ++i) {
FloatToS16(data_ptr[i], proc_samples_per_channel_,
channels_->ibuf()->channel(i));
FloatToFloatS16(data_ptr[i], proc_samples_per_channel_,
channels_->fbuf()->channel(i));
}
}
@ -241,16 +228,15 @@ void AudioBuffer::CopyTo(int samples_per_channel,
assert(samples_per_channel == output_samples_per_channel_);
assert(ChannelsFromLayout(layout) == num_proc_channels_);
// Convert to float.
// Convert to the float range.
float* const* data_ptr = data;
if (output_samples_per_channel_ != proc_samples_per_channel_) {
// Convert to an intermediate buffer for subsequent resampling.
data_ptr = process_buffer_->channels();
}
for (int i = 0; i < num_proc_channels_; ++i) {
S16ToFloat(channels_->ibuf()->channel(i),
proc_samples_per_channel_,
data_ptr[i]);
FloatS16ToFloat(channels_->fbuf()->channel(i), proc_samples_per_channel_,
data_ptr[i]);
}
// Resample.
@ -449,12 +435,7 @@ void AudioBuffer::DeinterleaveFrom(AudioFrame* frame) {
// Downmix directly; no explicit deinterleaving needed.
int16_t* downmixed = channels_->ibuf()->channel(0);
for (int i = 0; i < input_samples_per_channel_; ++i) {
// HACK(ajm): The downmixing in the int16_t path is in practice never
// called from production code. We do this weird scaling to and from float
// to satisfy tests checking for bit-exactness with the float path.
float downmix_float = (S16ToFloat(frame->data_[i * 2]) +
S16ToFloat(frame->data_[i * 2 + 1])) / 2;
downmixed[i] = FloatToS16(downmix_float);
downmixed[i] = (frame->data_[i * 2] + frame->data_[i * 2 + 1]) / 2;
}
} else {
assert(num_proc_channels_ == num_input_channels_);

View File

@ -96,14 +96,13 @@ int TruncateToMultipleOf10(int value) {
void MixStereoToMono(const float* stereo, float* mono,
int samples_per_channel) {
for (int i = 0; i < samples_per_channel; ++i) {
for (int i = 0; i < samples_per_channel; ++i)
mono[i] = (stereo[i * 2] + stereo[i * 2 + 1]) / 2;
}
}
void MixStereoToMono(const int16_t* stereo, int16_t* mono,
int samples_per_channel) {
for (int i = 0; i < samples_per_channel; i++)
for (int i = 0; i < samples_per_channel; ++i)
mono[i] = (stereo[i * 2] + stereo[i * 2 + 1]) >> 1;
}
@ -1650,7 +1649,7 @@ TEST_F(ApmTest, DebugDumpFromFileHandle) {
#endif // WEBRTC_AUDIOPROC_DEBUG_DUMP
}
TEST_F(ApmTest, FloatAndIntInterfacesGiveIdenticalResults) {
TEST_F(ApmTest, FloatAndIntInterfacesGiveSimilarResults) {
audioproc::OutputData ref_data;
OpenFileAndReadMessage(ref_filename_, &ref_data);
@ -1679,7 +1678,8 @@ TEST_F(ApmTest, FloatAndIntInterfacesGiveIdenticalResults) {
Init(fapm.get());
ChannelBuffer<int16_t> output_cb(samples_per_channel, num_input_channels);
scoped_ptr<int16_t[]> output_int16(new int16_t[output_length]);
ChannelBuffer<int16_t> output_int16(samples_per_channel,
num_input_channels);
int analog_level = 127;
while (ReadFrame(far_file_, revframe_, revfloat_cb_.get()) &&
@ -1701,7 +1701,9 @@ TEST_F(ApmTest, FloatAndIntInterfacesGiveIdenticalResults) {
EXPECT_NOERR(fapm->gain_control()->set_stream_analog_level(analog_level));
EXPECT_NOERR(apm_->ProcessStream(frame_));
// TODO(ajm): Update to support different output rates.
Deinterleave(frame_->data_, samples_per_channel, num_output_channels,
output_int16.channels());
EXPECT_NOERR(fapm->ProcessStream(
float_cb_->channels(),
samples_per_channel,
@ -1711,24 +1713,34 @@ TEST_F(ApmTest, FloatAndIntInterfacesGiveIdenticalResults) {
LayoutFromChannels(num_output_channels),
float_cb_->channels()));
// Convert to interleaved int16.
FloatToS16(float_cb_->data(), output_length, output_cb.data());
Interleave(output_cb.channels(),
samples_per_channel,
num_output_channels,
output_int16.get());
// Verify float and int16 paths produce identical output.
EXPECT_EQ(0, memcmp(frame_->data_, output_int16.get(), output_length));
for (int j = 0; j < num_output_channels; ++j) {
float variance = 0;
float snr = ComputeSNR(output_int16.channel(j), output_cb.channel(j),
samples_per_channel, &variance);
#if defined(WEBRTC_AUDIOPROC_FIXED_PROFILE)
// There are a few chunks in the fixed-point profile that give low SNR.
// Listening confirmed the difference is acceptable.
const float kVarianceThreshold = 150;
const float kSNRThreshold = 10;
#else
const float kVarianceThreshold = 20;
const float kSNRThreshold = 20;
#endif
// Skip frames with low energy.
if (sqrt(variance) > kVarianceThreshold) {
EXPECT_LT(kSNRThreshold, snr);
}
}
analog_level = fapm->gain_control()->stream_analog_level();
EXPECT_EQ(apm_->gain_control()->stream_analog_level(),
fapm->gain_control()->stream_analog_level());
EXPECT_EQ(apm_->echo_cancellation()->stream_has_echo(),
fapm->echo_cancellation()->stream_has_echo());
EXPECT_EQ(apm_->voice_detection()->stream_has_voice(),
fapm->voice_detection()->stream_has_voice());
EXPECT_EQ(apm_->noise_suppression()->speech_probability(),
fapm->noise_suppression()->speech_probability());
EXPECT_NEAR(apm_->noise_suppression()->speech_probability(),
fapm->noise_suppression()->speech_probability(),
0.0005);
// Reset in case of downmixing.
frame_->num_channels_ = test->num_input_channels();
@ -2109,7 +2121,9 @@ class AudioProcessingTest
int num_output_channels,
int num_reverse_channels,
std::string output_file_prefix) {
scoped_ptr<AudioProcessing> ap(AudioProcessing::Create());
Config config;
config.Set<ExperimentalAgc>(new ExperimentalAgc(false));
scoped_ptr<AudioProcessing> ap(AudioProcessing::Create(config));
EnableAllAPComponents(ap.get());
ap->Initialize(input_rate,
output_rate,

View File

@ -8,6 +8,7 @@
* be found in the AUTHORS file in the root of the source tree.
*/
#include <math.h>
#include <limits>
#include "webrtc/audio_processing/debug.pb.h"
@ -153,4 +154,26 @@ static inline bool ReadMessageFromFile(FILE* file,
return msg->ParseFromArray(bytes.get(), size);
}
template <typename T>
float ComputeSNR(const T* ref, const T* test, int length, float* variance) {
float mse = 0;
float mean = 0;
*variance = 0;
for (int i = 0; i < length; ++i) {
T error = ref[i] - test[i];
mse += error * error;
*variance += ref[i] * ref[i];
mean += ref[i];
}
mse /= length;
*variance /= length;
mean /= length;
*variance -= mean * mean;
float snr = 100; // We assign 100 dB to the zero-error case.
if (mse > 0)
snr = 10 * log10(*variance / mse);
return snr;
}
} // namespace webrtc