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-rw-r--r--third_party/libwebrtc/audio/utility/BUILD.gn56
-rw-r--r--third_party/libwebrtc/audio/utility/audio_frame_operations.cc294
-rw-r--r--third_party/libwebrtc/audio/utility/audio_frame_operations.h107
-rw-r--r--third_party/libwebrtc/audio/utility/audio_frame_operations_gn/moz.build238
-rw-r--r--third_party/libwebrtc/audio/utility/audio_frame_operations_unittest.cc622
-rw-r--r--third_party/libwebrtc/audio/utility/channel_mixer.cc99
-rw-r--r--third_party/libwebrtc/audio/utility/channel_mixer.h86
-rw-r--r--third_party/libwebrtc/audio/utility/channel_mixer_unittest.cc393
-rw-r--r--third_party/libwebrtc/audio/utility/channel_mixing_matrix.cc333
-rw-r--r--third_party/libwebrtc/audio/utility/channel_mixing_matrix.h76
-rw-r--r--third_party/libwebrtc/audio/utility/channel_mixing_matrix_unittest.cc476
11 files changed, 2780 insertions, 0 deletions
diff --git a/third_party/libwebrtc/audio/utility/BUILD.gn b/third_party/libwebrtc/audio/utility/BUILD.gn
new file mode 100644
index 0000000000..983b6286e4
--- /dev/null
+++ b/third_party/libwebrtc/audio/utility/BUILD.gn
@@ -0,0 +1,56 @@
+# Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
+#
+# Use of this source code is governed by a BSD-style license
+# that can be found in the LICENSE file in the root of the source
+# tree. An additional intellectual property rights grant can be found
+# in the file PATENTS. All contributing project authors may
+# be found in the AUTHORS file in the root of the source tree.
+import("../../webrtc.gni")
+
+group("utility") {
+ deps = [ ":audio_frame_operations" ]
+}
+
+rtc_library("audio_frame_operations") {
+ visibility = [ "*" ]
+ sources = [
+ "audio_frame_operations.cc",
+ "audio_frame_operations.h",
+ "channel_mixer.cc",
+ "channel_mixer.h",
+ "channel_mixing_matrix.cc",
+ "channel_mixing_matrix.h",
+ ]
+
+ deps = [
+ "../../api/audio:audio_frame_api",
+ "../../common_audio",
+ "../../rtc_base:checks",
+ "../../rtc_base:logging",
+ "../../rtc_base:safe_conversions",
+ "../../system_wrappers:field_trial",
+ ]
+ absl_deps = [ "//third_party/abseil-cpp/absl/base:core_headers" ]
+}
+
+if (rtc_include_tests) {
+ rtc_library("utility_tests") {
+ testonly = true
+ sources = [
+ "audio_frame_operations_unittest.cc",
+ "channel_mixer_unittest.cc",
+ "channel_mixing_matrix_unittest.cc",
+ ]
+ deps = [
+ ":audio_frame_operations",
+ "../../api/audio:audio_frame_api",
+ "../../rtc_base:checks",
+ "../../rtc_base:logging",
+ "../../rtc_base:macromagic",
+ "../../rtc_base:stringutils",
+ "../../test:field_trial",
+ "../../test:test_support",
+ "//testing/gtest",
+ ]
+ }
+}
diff --git a/third_party/libwebrtc/audio/utility/audio_frame_operations.cc b/third_party/libwebrtc/audio/utility/audio_frame_operations.cc
new file mode 100644
index 0000000000..1b936c239b
--- /dev/null
+++ b/third_party/libwebrtc/audio/utility/audio_frame_operations.cc
@@ -0,0 +1,294 @@
+/*
+ * Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "audio/utility/audio_frame_operations.h"
+
+#include <string.h>
+
+#include <algorithm>
+#include <cstdint>
+#include <utility>
+
+#include "common_audio/include/audio_util.h"
+#include "rtc_base/checks.h"
+#include "rtc_base/numerics/safe_conversions.h"
+
+namespace webrtc {
+namespace {
+
+// 2.7ms @ 48kHz, 4ms @ 32kHz, 8ms @ 16kHz.
+const size_t kMuteFadeFrames = 128;
+const float kMuteFadeInc = 1.0f / kMuteFadeFrames;
+
+} // namespace
+
+void AudioFrameOperations::Add(const AudioFrame& frame_to_add,
+ AudioFrame* result_frame) {
+ // Sanity check.
+ RTC_DCHECK(result_frame);
+ RTC_DCHECK_GT(result_frame->num_channels_, 0);
+ RTC_DCHECK_EQ(result_frame->num_channels_, frame_to_add.num_channels_);
+
+ bool no_previous_data = result_frame->muted();
+ if (result_frame->samples_per_channel_ != frame_to_add.samples_per_channel_) {
+ // Special case we have no data to start with.
+ RTC_DCHECK_EQ(result_frame->samples_per_channel_, 0);
+ result_frame->samples_per_channel_ = frame_to_add.samples_per_channel_;
+ no_previous_data = true;
+ }
+
+ if (result_frame->vad_activity_ == AudioFrame::kVadActive ||
+ frame_to_add.vad_activity_ == AudioFrame::kVadActive) {
+ result_frame->vad_activity_ = AudioFrame::kVadActive;
+ } else if (result_frame->vad_activity_ == AudioFrame::kVadUnknown ||
+ frame_to_add.vad_activity_ == AudioFrame::kVadUnknown) {
+ result_frame->vad_activity_ = AudioFrame::kVadUnknown;
+ }
+
+ if (result_frame->speech_type_ != frame_to_add.speech_type_)
+ result_frame->speech_type_ = AudioFrame::kUndefined;
+
+ if (!frame_to_add.muted()) {
+ const int16_t* in_data = frame_to_add.data();
+ int16_t* out_data = result_frame->mutable_data();
+ size_t length =
+ frame_to_add.samples_per_channel_ * frame_to_add.num_channels_;
+ if (no_previous_data) {
+ std::copy(in_data, in_data + length, out_data);
+ } else {
+ for (size_t i = 0; i < length; i++) {
+ const int32_t wrap_guard = static_cast<int32_t>(out_data[i]) +
+ static_cast<int32_t>(in_data[i]);
+ out_data[i] = rtc::saturated_cast<int16_t>(wrap_guard);
+ }
+ }
+ }
+}
+
+int AudioFrameOperations::MonoToStereo(AudioFrame* frame) {
+ if (frame->num_channels_ != 1) {
+ return -1;
+ }
+ UpmixChannels(2, frame);
+ return 0;
+}
+
+int AudioFrameOperations::StereoToMono(AudioFrame* frame) {
+ if (frame->num_channels_ != 2) {
+ return -1;
+ }
+ DownmixChannels(1, frame);
+ return frame->num_channels_ == 1 ? 0 : -1;
+}
+
+void AudioFrameOperations::QuadToStereo(const int16_t* src_audio,
+ size_t samples_per_channel,
+ int16_t* dst_audio) {
+ for (size_t i = 0; i < samples_per_channel; i++) {
+ dst_audio[i * 2] =
+ (static_cast<int32_t>(src_audio[4 * i]) + src_audio[4 * i + 1]) >> 1;
+ dst_audio[i * 2 + 1] =
+ (static_cast<int32_t>(src_audio[4 * i + 2]) + src_audio[4 * i + 3]) >>
+ 1;
+ }
+}
+
+int AudioFrameOperations::QuadToStereo(AudioFrame* frame) {
+ if (frame->num_channels_ != 4) {
+ return -1;
+ }
+
+ RTC_DCHECK_LE(frame->samples_per_channel_ * 4,
+ AudioFrame::kMaxDataSizeSamples);
+
+ if (!frame->muted()) {
+ QuadToStereo(frame->data(), frame->samples_per_channel_,
+ frame->mutable_data());
+ }
+ frame->num_channels_ = 2;
+
+ return 0;
+}
+
+void AudioFrameOperations::DownmixChannels(const int16_t* src_audio,
+ size_t src_channels,
+ size_t samples_per_channel,
+ size_t dst_channels,
+ int16_t* dst_audio) {
+ if (src_channels > 1 && dst_channels == 1) {
+ DownmixInterleavedToMono(src_audio, samples_per_channel, src_channels,
+ dst_audio);
+ return;
+ } else if (src_channels == 4 && dst_channels == 2) {
+ QuadToStereo(src_audio, samples_per_channel, dst_audio);
+ return;
+ }
+
+ RTC_DCHECK_NOTREACHED() << "src_channels: " << src_channels
+ << ", dst_channels: " << dst_channels;
+}
+
+void AudioFrameOperations::DownmixChannels(size_t dst_channels,
+ AudioFrame* frame) {
+ RTC_DCHECK_LE(frame->samples_per_channel_ * frame->num_channels_,
+ AudioFrame::kMaxDataSizeSamples);
+ if (frame->num_channels_ > 1 && dst_channels == 1) {
+ if (!frame->muted()) {
+ DownmixInterleavedToMono(frame->data(), frame->samples_per_channel_,
+ frame->num_channels_, frame->mutable_data());
+ }
+ frame->num_channels_ = 1;
+ } else if (frame->num_channels_ == 4 && dst_channels == 2) {
+ int err = QuadToStereo(frame);
+ RTC_DCHECK_EQ(err, 0);
+ } else {
+ RTC_DCHECK_NOTREACHED() << "src_channels: " << frame->num_channels_
+ << ", dst_channels: " << dst_channels;
+ }
+}
+
+void AudioFrameOperations::UpmixChannels(size_t target_number_of_channels,
+ AudioFrame* frame) {
+ RTC_DCHECK_EQ(frame->num_channels_, 1);
+ RTC_DCHECK_LE(frame->samples_per_channel_ * target_number_of_channels,
+ AudioFrame::kMaxDataSizeSamples);
+
+ if (frame->num_channels_ != 1 ||
+ frame->samples_per_channel_ * target_number_of_channels >
+ AudioFrame::kMaxDataSizeSamples) {
+ return;
+ }
+
+ if (!frame->muted()) {
+ // Up-mixing done in place. Going backwards through the frame ensure nothing
+ // is irrevocably overwritten.
+ int16_t* frame_data = frame->mutable_data();
+ for (int i = frame->samples_per_channel_ - 1; i >= 0; i--) {
+ for (size_t j = 0; j < target_number_of_channels; ++j) {
+ frame_data[target_number_of_channels * i + j] = frame_data[i];
+ }
+ }
+ }
+ frame->num_channels_ = target_number_of_channels;
+}
+
+void AudioFrameOperations::SwapStereoChannels(AudioFrame* frame) {
+ RTC_DCHECK(frame);
+ if (frame->num_channels_ != 2 || frame->muted()) {
+ return;
+ }
+
+ int16_t* frame_data = frame->mutable_data();
+ for (size_t i = 0; i < frame->samples_per_channel_ * 2; i += 2) {
+ std::swap(frame_data[i], frame_data[i + 1]);
+ }
+}
+
+void AudioFrameOperations::Mute(AudioFrame* frame,
+ bool previous_frame_muted,
+ bool current_frame_muted) {
+ RTC_DCHECK(frame);
+ if (!previous_frame_muted && !current_frame_muted) {
+ // Not muted, don't touch.
+ } else if (previous_frame_muted && current_frame_muted) {
+ // Frame fully muted.
+ size_t total_samples = frame->samples_per_channel_ * frame->num_channels_;
+ RTC_DCHECK_GE(AudioFrame::kMaxDataSizeSamples, total_samples);
+ frame->Mute();
+ } else {
+ // Fade is a no-op on a muted frame.
+ if (frame->muted()) {
+ return;
+ }
+
+ // Limit number of samples to fade, if frame isn't long enough.
+ size_t count = kMuteFadeFrames;
+ float inc = kMuteFadeInc;
+ if (frame->samples_per_channel_ < kMuteFadeFrames) {
+ count = frame->samples_per_channel_;
+ if (count > 0) {
+ inc = 1.0f / count;
+ }
+ }
+
+ size_t start = 0;
+ size_t end = count;
+ float start_g = 0.0f;
+ if (current_frame_muted) {
+ // Fade out the last `count` samples of frame.
+ RTC_DCHECK(!previous_frame_muted);
+ start = frame->samples_per_channel_ - count;
+ end = frame->samples_per_channel_;
+ start_g = 1.0f;
+ inc = -inc;
+ } else {
+ // Fade in the first `count` samples of frame.
+ RTC_DCHECK(previous_frame_muted);
+ }
+
+ // Perform fade.
+ int16_t* frame_data = frame->mutable_data();
+ size_t channels = frame->num_channels_;
+ for (size_t j = 0; j < channels; ++j) {
+ float g = start_g;
+ for (size_t i = start * channels; i < end * channels; i += channels) {
+ g += inc;
+ frame_data[i + j] *= g;
+ }
+ }
+ }
+}
+
+void AudioFrameOperations::Mute(AudioFrame* frame) {
+ Mute(frame, true, true);
+}
+
+void AudioFrameOperations::ApplyHalfGain(AudioFrame* frame) {
+ RTC_DCHECK(frame);
+ RTC_DCHECK_GT(frame->num_channels_, 0);
+ if (frame->num_channels_ < 1 || frame->muted()) {
+ return;
+ }
+
+ int16_t* frame_data = frame->mutable_data();
+ for (size_t i = 0; i < frame->samples_per_channel_ * frame->num_channels_;
+ i++) {
+ frame_data[i] = frame_data[i] >> 1;
+ }
+}
+
+int AudioFrameOperations::Scale(float left, float right, AudioFrame* frame) {
+ if (frame->num_channels_ != 2) {
+ return -1;
+ } else if (frame->muted()) {
+ return 0;
+ }
+
+ int16_t* frame_data = frame->mutable_data();
+ for (size_t i = 0; i < frame->samples_per_channel_; i++) {
+ frame_data[2 * i] = static_cast<int16_t>(left * frame_data[2 * i]);
+ frame_data[2 * i + 1] = static_cast<int16_t>(right * frame_data[2 * i + 1]);
+ }
+ return 0;
+}
+
+int AudioFrameOperations::ScaleWithSat(float scale, AudioFrame* frame) {
+ if (frame->muted()) {
+ return 0;
+ }
+
+ int16_t* frame_data = frame->mutable_data();
+ for (size_t i = 0; i < frame->samples_per_channel_ * frame->num_channels_;
+ i++) {
+ frame_data[i] = rtc::saturated_cast<int16_t>(scale * frame_data[i]);
+ }
+ return 0;
+}
+} // namespace webrtc
diff --git a/third_party/libwebrtc/audio/utility/audio_frame_operations.h b/third_party/libwebrtc/audio/utility/audio_frame_operations.h
new file mode 100644
index 0000000000..2a5f29f4f5
--- /dev/null
+++ b/third_party/libwebrtc/audio/utility/audio_frame_operations.h
@@ -0,0 +1,107 @@
+/*
+ * Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef AUDIO_UTILITY_AUDIO_FRAME_OPERATIONS_H_
+#define AUDIO_UTILITY_AUDIO_FRAME_OPERATIONS_H_
+
+#include <stddef.h>
+#include <stdint.h>
+
+#include "absl/base/attributes.h"
+#include "api/audio/audio_frame.h"
+
+namespace webrtc {
+
+// TODO(andrew): consolidate this with utility.h and audio_frame_manipulator.h.
+// Change reference parameters to pointers. Consider using a namespace rather
+// than a class.
+class AudioFrameOperations {
+ public:
+ // Add samples in `frame_to_add` with samples in `result_frame`
+ // putting the results in `results_frame`. The fields
+ // `vad_activity_` and `speech_type_` of the result frame are
+ // updated. If `result_frame` is empty (`samples_per_channel_`==0),
+ // the samples in `frame_to_add` are added to it. The number of
+ // channels and number of samples per channel must match except when
+ // `result_frame` is empty.
+ static void Add(const AudioFrame& frame_to_add, AudioFrame* result_frame);
+
+ // `frame.num_channels_` will be updated. This version checks for sufficient
+ // buffer size and that `num_channels_` is mono. Use UpmixChannels
+ // instead. TODO(bugs.webrtc.org/8649): remove.
+ ABSL_DEPRECATED("bugs.webrtc.org/8649")
+ static int MonoToStereo(AudioFrame* frame);
+
+ // `frame.num_channels_` will be updated. This version checks that
+ // `num_channels_` is stereo. Use DownmixChannels
+ // instead. TODO(bugs.webrtc.org/8649): remove.
+ ABSL_DEPRECATED("bugs.webrtc.org/8649")
+ static int StereoToMono(AudioFrame* frame);
+
+ // Downmixes 4 channels `src_audio` to stereo `dst_audio`. This is an in-place
+ // operation, meaning `src_audio` and `dst_audio` may point to the same
+ // buffer.
+ static void QuadToStereo(const int16_t* src_audio,
+ size_t samples_per_channel,
+ int16_t* dst_audio);
+
+ // `frame.num_channels_` will be updated. This version checks that
+ // `num_channels_` is 4 channels.
+ static int QuadToStereo(AudioFrame* frame);
+
+ // Downmixes `src_channels` `src_audio` to `dst_channels` `dst_audio`.
+ // This is an in-place operation, meaning `src_audio` and `dst_audio`
+ // may point to the same buffer. Supported channel combinations are
+ // Stereo to Mono, Quad to Mono, and Quad to Stereo.
+ static void DownmixChannels(const int16_t* src_audio,
+ size_t src_channels,
+ size_t samples_per_channel,
+ size_t dst_channels,
+ int16_t* dst_audio);
+
+ // `frame.num_channels_` will be updated. This version checks that
+ // `num_channels_` and `dst_channels` are valid and performs relevant downmix.
+ // Supported channel combinations are N channels to Mono, and Quad to Stereo.
+ static void DownmixChannels(size_t dst_channels, AudioFrame* frame);
+
+ // `frame.num_channels_` will be updated. This version checks that
+ // `num_channels_` and `dst_channels` are valid and performs relevant
+ // downmix. Supported channel combinations are Mono to N
+ // channels. The single channel is replicated.
+ static void UpmixChannels(size_t target_number_of_channels,
+ AudioFrame* frame);
+
+ // Swap the left and right channels of `frame`. Fails silently if `frame` is
+ // not stereo.
+ static void SwapStereoChannels(AudioFrame* frame);
+
+ // Conditionally zero out contents of `frame` for implementing audio mute:
+ // `previous_frame_muted` && `current_frame_muted` - Zero out whole frame.
+ // `previous_frame_muted` && !`current_frame_muted` - Fade-in at frame start.
+ // !`previous_frame_muted` && `current_frame_muted` - Fade-out at frame end.
+ // !`previous_frame_muted` && !`current_frame_muted` - Leave frame untouched.
+ static void Mute(AudioFrame* frame,
+ bool previous_frame_muted,
+ bool current_frame_muted);
+
+ // Zero out contents of frame.
+ static void Mute(AudioFrame* frame);
+
+ // Halve samples in `frame`.
+ static void ApplyHalfGain(AudioFrame* frame);
+
+ static int Scale(float left, float right, AudioFrame* frame);
+
+ static int ScaleWithSat(float scale, AudioFrame* frame);
+};
+
+} // namespace webrtc
+
+#endif // AUDIO_UTILITY_AUDIO_FRAME_OPERATIONS_H_
diff --git a/third_party/libwebrtc/audio/utility/audio_frame_operations_gn/moz.build b/third_party/libwebrtc/audio/utility/audio_frame_operations_gn/moz.build
new file mode 100644
index 0000000000..e215792f64
--- /dev/null
+++ b/third_party/libwebrtc/audio/utility/audio_frame_operations_gn/moz.build
@@ -0,0 +1,238 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+ ### This moz.build was AUTOMATICALLY GENERATED from a GN config, ###
+ ### DO NOT edit it by hand. ###
+
+COMPILE_FLAGS["OS_INCLUDES"] = []
+AllowCompilerWarnings()
+
+DEFINES["ABSL_ALLOCATOR_NOTHROW"] = "1"
+DEFINES["RTC_DAV1D_IN_INTERNAL_DECODER_FACTORY"] = True
+DEFINES["RTC_ENABLE_VP9"] = True
+DEFINES["WEBRTC_ENABLE_PROTOBUF"] = "0"
+DEFINES["WEBRTC_LIBRARY_IMPL"] = True
+DEFINES["WEBRTC_MOZILLA_BUILD"] = True
+DEFINES["WEBRTC_NON_STATIC_TRACE_EVENT_HANDLERS"] = "0"
+DEFINES["WEBRTC_STRICT_FIELD_TRIALS"] = "0"
+
+FINAL_LIBRARY = "webrtc"
+
+
+LOCAL_INCLUDES += [
+ "!/ipc/ipdl/_ipdlheaders",
+ "!/third_party/libwebrtc/gen",
+ "/ipc/chromium/src",
+ "/third_party/libwebrtc/",
+ "/third_party/libwebrtc/third_party/abseil-cpp/",
+ "/tools/profiler/public"
+]
+
+UNIFIED_SOURCES += [
+ "/third_party/libwebrtc/audio/utility/audio_frame_operations.cc",
+ "/third_party/libwebrtc/audio/utility/channel_mixer.cc",
+ "/third_party/libwebrtc/audio/utility/channel_mixing_matrix.cc"
+]
+
+if not CONFIG["MOZ_DEBUG"]:
+
+ DEFINES["DYNAMIC_ANNOTATIONS_ENABLED"] = "0"
+ DEFINES["NDEBUG"] = True
+ DEFINES["NVALGRIND"] = True
+
+if CONFIG["MOZ_DEBUG"] == "1":
+
+ DEFINES["DYNAMIC_ANNOTATIONS_ENABLED"] = "1"
+
+if CONFIG["OS_TARGET"] == "Android":
+
+ DEFINES["ANDROID"] = True
+ DEFINES["ANDROID_NDK_VERSION_ROLL"] = "r22_1"
+ DEFINES["HAVE_SYS_UIO_H"] = True
+ DEFINES["WEBRTC_ANDROID"] = True
+ DEFINES["WEBRTC_ANDROID_OPENSLES"] = True
+ DEFINES["WEBRTC_ENABLE_LIBEVENT"] = True
+ DEFINES["WEBRTC_LINUX"] = True
+ DEFINES["WEBRTC_POSIX"] = True
+ DEFINES["_GNU_SOURCE"] = True
+ DEFINES["__STDC_CONSTANT_MACROS"] = True
+ DEFINES["__STDC_FORMAT_MACROS"] = True
+
+ OS_LIBS += [
+ "log"
+ ]
+
+if CONFIG["OS_TARGET"] == "Darwin":
+
+ DEFINES["WEBRTC_MAC"] = True
+ DEFINES["WEBRTC_POSIX"] = True
+ DEFINES["_LIBCPP_HAS_NO_ALIGNED_ALLOCATION"] = True
+ DEFINES["__ASSERT_MACROS_DEFINE_VERSIONS_WITHOUT_UNDERSCORES"] = "0"
+ DEFINES["__STDC_CONSTANT_MACROS"] = True
+ DEFINES["__STDC_FORMAT_MACROS"] = True
+
+if CONFIG["OS_TARGET"] == "Linux":
+
+ DEFINES["USE_AURA"] = "1"
+ DEFINES["USE_GLIB"] = "1"
+ DEFINES["USE_NSS_CERTS"] = "1"
+ DEFINES["USE_OZONE"] = "1"
+ DEFINES["USE_UDEV"] = True
+ DEFINES["WEBRTC_ENABLE_LIBEVENT"] = True
+ DEFINES["WEBRTC_LINUX"] = True
+ DEFINES["WEBRTC_POSIX"] = True
+ DEFINES["_FILE_OFFSET_BITS"] = "64"
+ DEFINES["_LARGEFILE64_SOURCE"] = True
+ DEFINES["_LARGEFILE_SOURCE"] = True
+ DEFINES["__STDC_CONSTANT_MACROS"] = True
+ DEFINES["__STDC_FORMAT_MACROS"] = True
+
+ OS_LIBS += [
+ "rt"
+ ]
+
+if CONFIG["OS_TARGET"] == "OpenBSD":
+
+ DEFINES["USE_GLIB"] = "1"
+ DEFINES["USE_OZONE"] = "1"
+ DEFINES["USE_X11"] = "1"
+ DEFINES["WEBRTC_BSD"] = True
+ DEFINES["WEBRTC_ENABLE_LIBEVENT"] = True
+ DEFINES["WEBRTC_POSIX"] = True
+ DEFINES["_FILE_OFFSET_BITS"] = "64"
+ DEFINES["_LARGEFILE64_SOURCE"] = True
+ DEFINES["_LARGEFILE_SOURCE"] = True
+ DEFINES["__STDC_CONSTANT_MACROS"] = True
+ DEFINES["__STDC_FORMAT_MACROS"] = True
+
+if CONFIG["OS_TARGET"] == "WINNT":
+
+ DEFINES["CERT_CHAIN_PARA_HAS_EXTRA_FIELDS"] = True
+ DEFINES["NOMINMAX"] = True
+ DEFINES["NTDDI_VERSION"] = "0x0A000000"
+ DEFINES["PSAPI_VERSION"] = "2"
+ DEFINES["RTC_ENABLE_WIN_WGC"] = True
+ DEFINES["UNICODE"] = True
+ DEFINES["USE_AURA"] = "1"
+ DEFINES["WEBRTC_WIN"] = True
+ DEFINES["WIN32"] = True
+ DEFINES["WIN32_LEAN_AND_MEAN"] = True
+ DEFINES["WINAPI_FAMILY"] = "WINAPI_FAMILY_DESKTOP_APP"
+ DEFINES["WINVER"] = "0x0A00"
+ DEFINES["_ATL_NO_OPENGL"] = True
+ DEFINES["_CRT_RAND_S"] = True
+ DEFINES["_CRT_SECURE_NO_DEPRECATE"] = True
+ DEFINES["_ENABLE_EXTENDED_ALIGNED_STORAGE"] = True
+ DEFINES["_HAS_EXCEPTIONS"] = "0"
+ DEFINES["_HAS_NODISCARD"] = True
+ DEFINES["_SCL_SECURE_NO_DEPRECATE"] = True
+ DEFINES["_SECURE_ATL"] = True
+ DEFINES["_UNICODE"] = True
+ DEFINES["_WIN32_WINNT"] = "0x0A00"
+ DEFINES["_WINDOWS"] = True
+ DEFINES["__STD_C"] = True
+
+ OS_LIBS += [
+ "crypt32",
+ "iphlpapi",
+ "secur32",
+ "winmm"
+ ]
+
+if CONFIG["TARGET_CPU"] == "aarch64":
+
+ DEFINES["WEBRTC_ARCH_ARM64"] = True
+ DEFINES["WEBRTC_HAS_NEON"] = True
+
+if CONFIG["TARGET_CPU"] == "arm":
+
+ CXXFLAGS += [
+ "-mfpu=neon"
+ ]
+
+ DEFINES["WEBRTC_ARCH_ARM"] = True
+ DEFINES["WEBRTC_ARCH_ARM_V7"] = True
+ DEFINES["WEBRTC_HAS_NEON"] = True
+
+if CONFIG["TARGET_CPU"] == "mips32":
+
+ DEFINES["MIPS32_LE"] = True
+ DEFINES["MIPS_FPU_LE"] = True
+ DEFINES["_GNU_SOURCE"] = True
+
+if CONFIG["TARGET_CPU"] == "mips64":
+
+ DEFINES["_GNU_SOURCE"] = True
+
+if CONFIG["TARGET_CPU"] == "x86":
+
+ DEFINES["WEBRTC_ENABLE_AVX2"] = True
+
+if CONFIG["TARGET_CPU"] == "x86_64":
+
+ DEFINES["WEBRTC_ENABLE_AVX2"] = True
+
+if CONFIG["MOZ_DEBUG"] == "1" and CONFIG["OS_TARGET"] == "Android":
+
+ DEFINES["_DEBUG"] = True
+
+if CONFIG["MOZ_DEBUG"] == "1" and CONFIG["OS_TARGET"] == "Darwin":
+
+ DEFINES["_DEBUG"] = True
+
+if CONFIG["MOZ_DEBUG"] == "1" and CONFIG["OS_TARGET"] == "Linux":
+
+ DEFINES["_DEBUG"] = True
+
+if CONFIG["MOZ_DEBUG"] == "1" and CONFIG["OS_TARGET"] == "OpenBSD":
+
+ DEFINES["_DEBUG"] = True
+
+if CONFIG["MOZ_DEBUG"] == "1" and CONFIG["OS_TARGET"] == "WINNT":
+
+ DEFINES["_HAS_ITERATOR_DEBUGGING"] = "0"
+
+if CONFIG["MOZ_X11"] == "1" and CONFIG["OS_TARGET"] == "Linux":
+
+ DEFINES["USE_X11"] = "1"
+
+if CONFIG["OS_TARGET"] == "Android" and CONFIG["TARGET_CPU"] == "arm":
+
+ OS_LIBS += [
+ "android_support",
+ "unwind"
+ ]
+
+if CONFIG["OS_TARGET"] == "Android" and CONFIG["TARGET_CPU"] == "x86":
+
+ CXXFLAGS += [
+ "-msse2"
+ ]
+
+ OS_LIBS += [
+ "android_support"
+ ]
+
+if CONFIG["OS_TARGET"] == "Linux" and CONFIG["TARGET_CPU"] == "aarch64":
+
+ DEFINES["_GNU_SOURCE"] = True
+
+if CONFIG["OS_TARGET"] == "Linux" and CONFIG["TARGET_CPU"] == "arm":
+
+ DEFINES["_GNU_SOURCE"] = True
+
+if CONFIG["OS_TARGET"] == "Linux" and CONFIG["TARGET_CPU"] == "x86":
+
+ CXXFLAGS += [
+ "-msse2"
+ ]
+
+ DEFINES["_GNU_SOURCE"] = True
+
+if CONFIG["OS_TARGET"] == "Linux" and CONFIG["TARGET_CPU"] == "x86_64":
+
+ DEFINES["_GNU_SOURCE"] = True
+
+Library("audio_frame_operations_gn")
diff --git a/third_party/libwebrtc/audio/utility/audio_frame_operations_unittest.cc b/third_party/libwebrtc/audio/utility/audio_frame_operations_unittest.cc
new file mode 100644
index 0000000000..1a2c16e45f
--- /dev/null
+++ b/third_party/libwebrtc/audio/utility/audio_frame_operations_unittest.cc
@@ -0,0 +1,622 @@
+/*
+ * Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "audio/utility/audio_frame_operations.h"
+
+#include "rtc_base/checks.h"
+#include "test/gtest.h"
+
+namespace webrtc {
+namespace {
+
+class AudioFrameOperationsTest : public ::testing::Test {
+ protected:
+ AudioFrameOperationsTest() {
+ // Set typical values.
+ frame_.samples_per_channel_ = 320;
+ frame_.num_channels_ = 2;
+ }
+
+ AudioFrame frame_;
+};
+
+class AudioFrameOperationsDeathTest : public AudioFrameOperationsTest {};
+
+void SetFrameData(int16_t ch1,
+ int16_t ch2,
+ int16_t ch3,
+ int16_t ch4,
+ AudioFrame* frame) {
+ int16_t* frame_data = frame->mutable_data();
+ for (size_t i = 0; i < frame->samples_per_channel_ * 4; i += 4) {
+ frame_data[i] = ch1;
+ frame_data[i + 1] = ch2;
+ frame_data[i + 2] = ch3;
+ frame_data[i + 3] = ch4;
+ }
+}
+
+void SetFrameData(int16_t left, int16_t right, AudioFrame* frame) {
+ int16_t* frame_data = frame->mutable_data();
+ for (size_t i = 0; i < frame->samples_per_channel_ * 2; i += 2) {
+ frame_data[i] = left;
+ frame_data[i + 1] = right;
+ }
+}
+
+void SetFrameData(int16_t data, AudioFrame* frame) {
+ int16_t* frame_data = frame->mutable_data();
+ for (size_t i = 0; i < frame->samples_per_channel_ * frame->num_channels_;
+ i++) {
+ frame_data[i] = data;
+ }
+}
+
+void VerifyFramesAreEqual(const AudioFrame& frame1, const AudioFrame& frame2) {
+ EXPECT_EQ(frame1.num_channels_, frame2.num_channels_);
+ EXPECT_EQ(frame1.samples_per_channel_, frame2.samples_per_channel_);
+ const int16_t* frame1_data = frame1.data();
+ const int16_t* frame2_data = frame2.data();
+ for (size_t i = 0; i < frame1.samples_per_channel_ * frame1.num_channels_;
+ i++) {
+ EXPECT_EQ(frame1_data[i], frame2_data[i]);
+ }
+ EXPECT_EQ(frame1.muted(), frame2.muted());
+}
+
+void InitFrame(AudioFrame* frame,
+ size_t channels,
+ size_t samples_per_channel,
+ int16_t left_data,
+ int16_t right_data) {
+ RTC_DCHECK(frame);
+ RTC_DCHECK_GE(2, channels);
+ RTC_DCHECK_GE(AudioFrame::kMaxDataSizeSamples,
+ samples_per_channel * channels);
+ frame->samples_per_channel_ = samples_per_channel;
+ frame->num_channels_ = channels;
+ if (channels == 2) {
+ SetFrameData(left_data, right_data, frame);
+ } else if (channels == 1) {
+ SetFrameData(left_data, frame);
+ }
+}
+
+int16_t GetChannelData(const AudioFrame& frame, size_t channel, size_t index) {
+ RTC_DCHECK_LT(channel, frame.num_channels_);
+ RTC_DCHECK_LT(index, frame.samples_per_channel_);
+ return frame.data()[index * frame.num_channels_ + channel];
+}
+
+void VerifyFrameDataBounds(const AudioFrame& frame,
+ size_t channel,
+ int16_t max,
+ int16_t min) {
+ for (size_t i = 0; i < frame.samples_per_channel_; ++i) {
+ int16_t s = GetChannelData(frame, channel, i);
+ EXPECT_LE(min, s);
+ EXPECT_GE(max, s);
+ }
+}
+
+#if RTC_DCHECK_IS_ON && GTEST_HAS_DEATH_TEST && !defined(WEBRTC_ANDROID)
+TEST_F(AudioFrameOperationsDeathTest, MonoToStereoFailsWithBadParameters) {
+ EXPECT_DEATH(AudioFrameOperations::UpmixChannels(2, &frame_), "");
+ frame_.samples_per_channel_ = AudioFrame::kMaxDataSizeSamples;
+ frame_.num_channels_ = 1;
+ EXPECT_DEATH(AudioFrameOperations::UpmixChannels(2, &frame_), "");
+}
+#endif
+
+TEST_F(AudioFrameOperationsTest, MonoToStereoSucceeds) {
+ frame_.num_channels_ = 1;
+ SetFrameData(1, &frame_);
+
+ AudioFrameOperations::UpmixChannels(2, &frame_);
+ EXPECT_EQ(2u, frame_.num_channels_);
+
+ AudioFrame stereo_frame;
+ stereo_frame.samples_per_channel_ = 320;
+ stereo_frame.num_channels_ = 2;
+ SetFrameData(1, 1, &stereo_frame);
+ VerifyFramesAreEqual(stereo_frame, frame_);
+}
+
+TEST_F(AudioFrameOperationsTest, MonoToStereoMuted) {
+ frame_.num_channels_ = 1;
+ ASSERT_TRUE(frame_.muted());
+ AudioFrameOperations::UpmixChannels(2, &frame_);
+ EXPECT_EQ(2u, frame_.num_channels_);
+ EXPECT_TRUE(frame_.muted());
+}
+
+#if RTC_DCHECK_IS_ON && GTEST_HAS_DEATH_TEST && !defined(WEBRTC_ANDROID)
+TEST_F(AudioFrameOperationsDeathTest, StereoToMonoFailsWithBadParameters) {
+ frame_.num_channels_ = 1;
+ EXPECT_DEATH(AudioFrameOperations::DownmixChannels(1, &frame_), "");
+}
+#endif
+
+TEST_F(AudioFrameOperationsTest, StereoToMonoSucceeds) {
+ SetFrameData(4, 2, &frame_);
+ AudioFrameOperations::DownmixChannels(1, &frame_);
+ EXPECT_EQ(1u, frame_.num_channels_);
+
+ AudioFrame mono_frame;
+ mono_frame.samples_per_channel_ = 320;
+ mono_frame.num_channels_ = 1;
+ SetFrameData(3, &mono_frame);
+ VerifyFramesAreEqual(mono_frame, frame_);
+}
+
+TEST_F(AudioFrameOperationsTest, StereoToMonoMuted) {
+ ASSERT_TRUE(frame_.muted());
+ AudioFrameOperations::DownmixChannels(1, &frame_);
+ EXPECT_EQ(1u, frame_.num_channels_);
+ EXPECT_TRUE(frame_.muted());
+}
+
+TEST_F(AudioFrameOperationsTest, StereoToMonoBufferSucceeds) {
+ AudioFrame target_frame;
+ SetFrameData(4, 2, &frame_);
+
+ target_frame.num_channels_ = 1;
+ target_frame.samples_per_channel_ = frame_.samples_per_channel_;
+
+ AudioFrameOperations::DownmixChannels(frame_.data(), 2,
+ frame_.samples_per_channel_, 1,
+ target_frame.mutable_data());
+
+ AudioFrame mono_frame;
+ mono_frame.samples_per_channel_ = 320;
+ mono_frame.num_channels_ = 1;
+ SetFrameData(3, &mono_frame);
+ VerifyFramesAreEqual(mono_frame, target_frame);
+}
+
+TEST_F(AudioFrameOperationsTest, StereoToMonoDoesNotWrapAround) {
+ SetFrameData(-32768, -32768, &frame_);
+ AudioFrameOperations::DownmixChannels(1, &frame_);
+ EXPECT_EQ(1u, frame_.num_channels_);
+ AudioFrame mono_frame;
+ mono_frame.samples_per_channel_ = 320;
+ mono_frame.num_channels_ = 1;
+ SetFrameData(-32768, &mono_frame);
+ VerifyFramesAreEqual(mono_frame, frame_);
+}
+
+TEST_F(AudioFrameOperationsTest, QuadToMonoSucceeds) {
+ frame_.num_channels_ = 4;
+ SetFrameData(4, 2, 6, 8, &frame_);
+
+ AudioFrameOperations::DownmixChannels(1, &frame_);
+ EXPECT_EQ(1u, frame_.num_channels_);
+
+ AudioFrame mono_frame;
+ mono_frame.samples_per_channel_ = 320;
+ mono_frame.num_channels_ = 1;
+ SetFrameData(5, &mono_frame);
+ VerifyFramesAreEqual(mono_frame, frame_);
+}
+
+TEST_F(AudioFrameOperationsTest, QuadToMonoMuted) {
+ frame_.num_channels_ = 4;
+ ASSERT_TRUE(frame_.muted());
+ AudioFrameOperations::DownmixChannels(1, &frame_);
+ EXPECT_EQ(1u, frame_.num_channels_);
+ EXPECT_TRUE(frame_.muted());
+}
+
+TEST_F(AudioFrameOperationsTest, QuadToMonoBufferSucceeds) {
+ AudioFrame target_frame;
+ frame_.num_channels_ = 4;
+ SetFrameData(4, 2, 6, 8, &frame_);
+
+ target_frame.num_channels_ = 1;
+ target_frame.samples_per_channel_ = frame_.samples_per_channel_;
+
+ AudioFrameOperations::DownmixChannels(frame_.data(), 4,
+ frame_.samples_per_channel_, 1,
+ target_frame.mutable_data());
+ AudioFrame mono_frame;
+ mono_frame.samples_per_channel_ = 320;
+ mono_frame.num_channels_ = 1;
+ SetFrameData(5, &mono_frame);
+ VerifyFramesAreEqual(mono_frame, target_frame);
+}
+
+TEST_F(AudioFrameOperationsTest, QuadToMonoDoesNotWrapAround) {
+ frame_.num_channels_ = 4;
+ SetFrameData(-32768, -32768, -32768, -32768, &frame_);
+ AudioFrameOperations::DownmixChannels(1, &frame_);
+ EXPECT_EQ(1u, frame_.num_channels_);
+
+ AudioFrame mono_frame;
+ mono_frame.samples_per_channel_ = 320;
+ mono_frame.num_channels_ = 1;
+ SetFrameData(-32768, &mono_frame);
+ VerifyFramesAreEqual(mono_frame, frame_);
+}
+
+TEST_F(AudioFrameOperationsTest, QuadToStereoFailsWithBadParameters) {
+ frame_.num_channels_ = 1;
+ EXPECT_EQ(-1, AudioFrameOperations::QuadToStereo(&frame_));
+ frame_.num_channels_ = 2;
+ EXPECT_EQ(-1, AudioFrameOperations::QuadToStereo(&frame_));
+}
+
+TEST_F(AudioFrameOperationsTest, QuadToStereoSucceeds) {
+ frame_.num_channels_ = 4;
+ SetFrameData(4, 2, 6, 8, &frame_);
+ EXPECT_EQ(0, AudioFrameOperations::QuadToStereo(&frame_));
+
+ AudioFrame stereo_frame;
+ stereo_frame.samples_per_channel_ = 320;
+ stereo_frame.num_channels_ = 2;
+ SetFrameData(3, 7, &stereo_frame);
+ VerifyFramesAreEqual(stereo_frame, frame_);
+}
+
+TEST_F(AudioFrameOperationsTest, QuadToStereoMuted) {
+ frame_.num_channels_ = 4;
+ ASSERT_TRUE(frame_.muted());
+ EXPECT_EQ(0, AudioFrameOperations::QuadToStereo(&frame_));
+ EXPECT_TRUE(frame_.muted());
+}
+
+TEST_F(AudioFrameOperationsTest, QuadToStereoBufferSucceeds) {
+ AudioFrame target_frame;
+ frame_.num_channels_ = 4;
+ SetFrameData(4, 2, 6, 8, &frame_);
+
+ target_frame.num_channels_ = 2;
+ target_frame.samples_per_channel_ = frame_.samples_per_channel_;
+
+ AudioFrameOperations::QuadToStereo(frame_.data(), frame_.samples_per_channel_,
+ target_frame.mutable_data());
+ AudioFrame stereo_frame;
+ stereo_frame.samples_per_channel_ = 320;
+ stereo_frame.num_channels_ = 2;
+ SetFrameData(3, 7, &stereo_frame);
+ VerifyFramesAreEqual(stereo_frame, target_frame);
+}
+
+TEST_F(AudioFrameOperationsTest, QuadToStereoDoesNotWrapAround) {
+ frame_.num_channels_ = 4;
+ SetFrameData(-32768, -32768, -32768, -32768, &frame_);
+ EXPECT_EQ(0, AudioFrameOperations::QuadToStereo(&frame_));
+
+ AudioFrame stereo_frame;
+ stereo_frame.samples_per_channel_ = 320;
+ stereo_frame.num_channels_ = 2;
+ SetFrameData(-32768, -32768, &stereo_frame);
+ VerifyFramesAreEqual(stereo_frame, frame_);
+}
+
+TEST_F(AudioFrameOperationsTest, SwapStereoChannelsSucceedsOnStereo) {
+ SetFrameData(0, 1, &frame_);
+
+ AudioFrame swapped_frame;
+ swapped_frame.samples_per_channel_ = 320;
+ swapped_frame.num_channels_ = 2;
+ SetFrameData(1, 0, &swapped_frame);
+
+ AudioFrameOperations::SwapStereoChannels(&frame_);
+ VerifyFramesAreEqual(swapped_frame, frame_);
+}
+
+TEST_F(AudioFrameOperationsTest, SwapStereoChannelsMuted) {
+ ASSERT_TRUE(frame_.muted());
+ AudioFrameOperations::SwapStereoChannels(&frame_);
+ EXPECT_TRUE(frame_.muted());
+}
+
+TEST_F(AudioFrameOperationsTest, SwapStereoChannelsFailsOnMono) {
+ frame_.num_channels_ = 1;
+ // Set data to "stereo", despite it being a mono frame.
+ SetFrameData(0, 1, &frame_);
+
+ AudioFrame orig_frame;
+ orig_frame.CopyFrom(frame_);
+ AudioFrameOperations::SwapStereoChannels(&frame_);
+ // Verify that no swap occurred.
+ VerifyFramesAreEqual(orig_frame, frame_);
+}
+
+TEST_F(AudioFrameOperationsTest, MuteDisabled) {
+ SetFrameData(1000, -1000, &frame_);
+ AudioFrameOperations::Mute(&frame_, false, false);
+
+ AudioFrame muted_frame;
+ muted_frame.samples_per_channel_ = 320;
+ muted_frame.num_channels_ = 2;
+ SetFrameData(1000, -1000, &muted_frame);
+ VerifyFramesAreEqual(muted_frame, frame_);
+}
+
+TEST_F(AudioFrameOperationsTest, MuteEnabled) {
+ SetFrameData(1000, -1000, &frame_);
+ AudioFrameOperations::Mute(&frame_, true, true);
+
+ AudioFrame muted_frame;
+ muted_frame.samples_per_channel_ = frame_.samples_per_channel_;
+ muted_frame.num_channels_ = frame_.num_channels_;
+ ASSERT_TRUE(muted_frame.muted());
+ VerifyFramesAreEqual(muted_frame, frame_);
+}
+
+// Verify that *beginning* to mute works for short and long (>128) frames, mono
+// and stereo. Beginning mute should yield a ramp down to zero.
+TEST_F(AudioFrameOperationsTest, MuteBeginMonoLong) {
+ InitFrame(&frame_, 1, 228, 1000, -1000);
+ AudioFrameOperations::Mute(&frame_, false, true);
+ VerifyFrameDataBounds(frame_, 0, 1000, 0);
+ EXPECT_EQ(1000, GetChannelData(frame_, 0, 99));
+ EXPECT_EQ(992, GetChannelData(frame_, 0, 100));
+ EXPECT_EQ(7, GetChannelData(frame_, 0, 226));
+ EXPECT_EQ(0, GetChannelData(frame_, 0, 227));
+}
+
+TEST_F(AudioFrameOperationsTest, MuteBeginMonoShort) {
+ InitFrame(&frame_, 1, 93, 1000, -1000);
+ AudioFrameOperations::Mute(&frame_, false, true);
+ VerifyFrameDataBounds(frame_, 0, 1000, 0);
+ EXPECT_EQ(989, GetChannelData(frame_, 0, 0));
+ EXPECT_EQ(978, GetChannelData(frame_, 0, 1));
+ EXPECT_EQ(10, GetChannelData(frame_, 0, 91));
+ EXPECT_EQ(0, GetChannelData(frame_, 0, 92));
+}
+
+TEST_F(AudioFrameOperationsTest, MuteBeginStereoLong) {
+ InitFrame(&frame_, 2, 228, 1000, -1000);
+ AudioFrameOperations::Mute(&frame_, false, true);
+ VerifyFrameDataBounds(frame_, 0, 1000, 0);
+ VerifyFrameDataBounds(frame_, 1, 0, -1000);
+ EXPECT_EQ(1000, GetChannelData(frame_, 0, 99));
+ EXPECT_EQ(-1000, GetChannelData(frame_, 1, 99));
+ EXPECT_EQ(992, GetChannelData(frame_, 0, 100));
+ EXPECT_EQ(-992, GetChannelData(frame_, 1, 100));
+ EXPECT_EQ(7, GetChannelData(frame_, 0, 226));
+ EXPECT_EQ(-7, GetChannelData(frame_, 1, 226));
+ EXPECT_EQ(0, GetChannelData(frame_, 0, 227));
+ EXPECT_EQ(0, GetChannelData(frame_, 1, 227));
+}
+
+TEST_F(AudioFrameOperationsTest, MuteBeginStereoShort) {
+ InitFrame(&frame_, 2, 93, 1000, -1000);
+ AudioFrameOperations::Mute(&frame_, false, true);
+ VerifyFrameDataBounds(frame_, 0, 1000, 0);
+ VerifyFrameDataBounds(frame_, 1, 0, -1000);
+ EXPECT_EQ(989, GetChannelData(frame_, 0, 0));
+ EXPECT_EQ(-989, GetChannelData(frame_, 1, 0));
+ EXPECT_EQ(978, GetChannelData(frame_, 0, 1));
+ EXPECT_EQ(-978, GetChannelData(frame_, 1, 1));
+ EXPECT_EQ(10, GetChannelData(frame_, 0, 91));
+ EXPECT_EQ(-10, GetChannelData(frame_, 1, 91));
+ EXPECT_EQ(0, GetChannelData(frame_, 0, 92));
+ EXPECT_EQ(0, GetChannelData(frame_, 1, 92));
+}
+
+// Verify that *ending* to mute works for short and long (>128) frames, mono
+// and stereo. Ending mute should yield a ramp up from zero.
+TEST_F(AudioFrameOperationsTest, MuteEndMonoLong) {
+ InitFrame(&frame_, 1, 228, 1000, -1000);
+ AudioFrameOperations::Mute(&frame_, true, false);
+ VerifyFrameDataBounds(frame_, 0, 1000, 0);
+ EXPECT_EQ(7, GetChannelData(frame_, 0, 0));
+ EXPECT_EQ(15, GetChannelData(frame_, 0, 1));
+ EXPECT_EQ(1000, GetChannelData(frame_, 0, 127));
+ EXPECT_EQ(1000, GetChannelData(frame_, 0, 128));
+}
+
+TEST_F(AudioFrameOperationsTest, MuteEndMonoShort) {
+ InitFrame(&frame_, 1, 93, 1000, -1000);
+ AudioFrameOperations::Mute(&frame_, true, false);
+ VerifyFrameDataBounds(frame_, 0, 1000, 0);
+ EXPECT_EQ(10, GetChannelData(frame_, 0, 0));
+ EXPECT_EQ(21, GetChannelData(frame_, 0, 1));
+ EXPECT_EQ(989, GetChannelData(frame_, 0, 91));
+ EXPECT_EQ(999, GetChannelData(frame_, 0, 92));
+}
+
+TEST_F(AudioFrameOperationsTest, MuteEndStereoLong) {
+ InitFrame(&frame_, 2, 228, 1000, -1000);
+ AudioFrameOperations::Mute(&frame_, true, false);
+ VerifyFrameDataBounds(frame_, 0, 1000, 0);
+ VerifyFrameDataBounds(frame_, 1, 0, -1000);
+ EXPECT_EQ(7, GetChannelData(frame_, 0, 0));
+ EXPECT_EQ(-7, GetChannelData(frame_, 1, 0));
+ EXPECT_EQ(15, GetChannelData(frame_, 0, 1));
+ EXPECT_EQ(-15, GetChannelData(frame_, 1, 1));
+ EXPECT_EQ(1000, GetChannelData(frame_, 0, 127));
+ EXPECT_EQ(-1000, GetChannelData(frame_, 1, 127));
+ EXPECT_EQ(1000, GetChannelData(frame_, 0, 128));
+ EXPECT_EQ(-1000, GetChannelData(frame_, 1, 128));
+}
+
+TEST_F(AudioFrameOperationsTest, MuteEndStereoShort) {
+ InitFrame(&frame_, 2, 93, 1000, -1000);
+ AudioFrameOperations::Mute(&frame_, true, false);
+ VerifyFrameDataBounds(frame_, 0, 1000, 0);
+ VerifyFrameDataBounds(frame_, 1, 0, -1000);
+ EXPECT_EQ(10, GetChannelData(frame_, 0, 0));
+ EXPECT_EQ(-10, GetChannelData(frame_, 1, 0));
+ EXPECT_EQ(21, GetChannelData(frame_, 0, 1));
+ EXPECT_EQ(-21, GetChannelData(frame_, 1, 1));
+ EXPECT_EQ(989, GetChannelData(frame_, 0, 91));
+ EXPECT_EQ(-989, GetChannelData(frame_, 1, 91));
+ EXPECT_EQ(999, GetChannelData(frame_, 0, 92));
+ EXPECT_EQ(-999, GetChannelData(frame_, 1, 92));
+}
+
+TEST_F(AudioFrameOperationsTest, MuteBeginAlreadyMuted) {
+ ASSERT_TRUE(frame_.muted());
+ AudioFrameOperations::Mute(&frame_, false, true);
+ EXPECT_TRUE(frame_.muted());
+}
+
+TEST_F(AudioFrameOperationsTest, MuteEndAlreadyMuted) {
+ ASSERT_TRUE(frame_.muted());
+ AudioFrameOperations::Mute(&frame_, true, false);
+ EXPECT_TRUE(frame_.muted());
+}
+
+TEST_F(AudioFrameOperationsTest, ApplyHalfGainSucceeds) {
+ SetFrameData(2, &frame_);
+
+ AudioFrame half_gain_frame;
+ half_gain_frame.num_channels_ = frame_.num_channels_;
+ half_gain_frame.samples_per_channel_ = frame_.samples_per_channel_;
+ SetFrameData(1, &half_gain_frame);
+
+ AudioFrameOperations::ApplyHalfGain(&frame_);
+ VerifyFramesAreEqual(half_gain_frame, frame_);
+}
+
+TEST_F(AudioFrameOperationsTest, ApplyHalfGainMuted) {
+ ASSERT_TRUE(frame_.muted());
+ AudioFrameOperations::ApplyHalfGain(&frame_);
+ EXPECT_TRUE(frame_.muted());
+}
+
+// TODO(andrew): should not allow negative scales.
+TEST_F(AudioFrameOperationsTest, DISABLED_ScaleFailsWithBadParameters) {
+ frame_.num_channels_ = 1;
+ EXPECT_EQ(-1, AudioFrameOperations::Scale(1.0, 1.0, &frame_));
+
+ frame_.num_channels_ = 3;
+ EXPECT_EQ(-1, AudioFrameOperations::Scale(1.0, 1.0, &frame_));
+
+ frame_.num_channels_ = 2;
+ EXPECT_EQ(-1, AudioFrameOperations::Scale(-1.0, 1.0, &frame_));
+ EXPECT_EQ(-1, AudioFrameOperations::Scale(1.0, -1.0, &frame_));
+}
+
+// TODO(andrew): fix the wraparound bug. We should always saturate.
+TEST_F(AudioFrameOperationsTest, DISABLED_ScaleDoesNotWrapAround) {
+ SetFrameData(4000, -4000, &frame_);
+ EXPECT_EQ(0, AudioFrameOperations::Scale(10.0, 10.0, &frame_));
+
+ AudioFrame clipped_frame;
+ clipped_frame.samples_per_channel_ = 320;
+ clipped_frame.num_channels_ = 2;
+ SetFrameData(32767, -32768, &clipped_frame);
+ VerifyFramesAreEqual(clipped_frame, frame_);
+}
+
+TEST_F(AudioFrameOperationsTest, ScaleSucceeds) {
+ SetFrameData(1, -1, &frame_);
+ EXPECT_EQ(0, AudioFrameOperations::Scale(2.0, 3.0, &frame_));
+
+ AudioFrame scaled_frame;
+ scaled_frame.samples_per_channel_ = 320;
+ scaled_frame.num_channels_ = 2;
+ SetFrameData(2, -3, &scaled_frame);
+ VerifyFramesAreEqual(scaled_frame, frame_);
+}
+
+TEST_F(AudioFrameOperationsTest, ScaleMuted) {
+ ASSERT_TRUE(frame_.muted());
+ EXPECT_EQ(0, AudioFrameOperations::Scale(2.0, 3.0, &frame_));
+ EXPECT_TRUE(frame_.muted());
+}
+
+// TODO(andrew): should fail with a negative scale.
+TEST_F(AudioFrameOperationsTest, DISABLED_ScaleWithSatFailsWithBadParameters) {
+ EXPECT_EQ(-1, AudioFrameOperations::ScaleWithSat(-1.0, &frame_));
+}
+
+TEST_F(AudioFrameOperationsTest, ScaleWithSatDoesNotWrapAround) {
+ frame_.num_channels_ = 1;
+ SetFrameData(4000, &frame_);
+ EXPECT_EQ(0, AudioFrameOperations::ScaleWithSat(10.0, &frame_));
+
+ AudioFrame clipped_frame;
+ clipped_frame.samples_per_channel_ = 320;
+ clipped_frame.num_channels_ = 1;
+ SetFrameData(32767, &clipped_frame);
+ VerifyFramesAreEqual(clipped_frame, frame_);
+
+ SetFrameData(-4000, &frame_);
+ EXPECT_EQ(0, AudioFrameOperations::ScaleWithSat(10.0, &frame_));
+ SetFrameData(-32768, &clipped_frame);
+ VerifyFramesAreEqual(clipped_frame, frame_);
+}
+
+TEST_F(AudioFrameOperationsTest, ScaleWithSatSucceeds) {
+ frame_.num_channels_ = 1;
+ SetFrameData(1, &frame_);
+ EXPECT_EQ(0, AudioFrameOperations::ScaleWithSat(2.0, &frame_));
+
+ AudioFrame scaled_frame;
+ scaled_frame.samples_per_channel_ = 320;
+ scaled_frame.num_channels_ = 1;
+ SetFrameData(2, &scaled_frame);
+ VerifyFramesAreEqual(scaled_frame, frame_);
+}
+
+TEST_F(AudioFrameOperationsTest, ScaleWithSatMuted) {
+ ASSERT_TRUE(frame_.muted());
+ EXPECT_EQ(0, AudioFrameOperations::ScaleWithSat(2.0, &frame_));
+ EXPECT_TRUE(frame_.muted());
+}
+
+TEST_F(AudioFrameOperationsTest, AddingXToEmptyGivesX) {
+ // When samples_per_channel_ is 0, the frame counts as empty and zero.
+ AudioFrame frame_to_add_to;
+ frame_to_add_to.mutable_data(); // Unmute the frame.
+ ASSERT_FALSE(frame_to_add_to.muted());
+ frame_to_add_to.samples_per_channel_ = 0;
+ frame_to_add_to.num_channels_ = frame_.num_channels_;
+
+ SetFrameData(1000, &frame_);
+ AudioFrameOperations::Add(frame_, &frame_to_add_to);
+ VerifyFramesAreEqual(frame_, frame_to_add_to);
+}
+
+TEST_F(AudioFrameOperationsTest, AddingXToMutedGivesX) {
+ AudioFrame frame_to_add_to;
+ ASSERT_TRUE(frame_to_add_to.muted());
+ frame_to_add_to.samples_per_channel_ = frame_.samples_per_channel_;
+ frame_to_add_to.num_channels_ = frame_.num_channels_;
+
+ SetFrameData(1000, &frame_);
+ AudioFrameOperations::Add(frame_, &frame_to_add_to);
+ VerifyFramesAreEqual(frame_, frame_to_add_to);
+}
+
+TEST_F(AudioFrameOperationsTest, AddingMutedToXGivesX) {
+ AudioFrame frame_to_add_to;
+ frame_to_add_to.samples_per_channel_ = frame_.samples_per_channel_;
+ frame_to_add_to.num_channels_ = frame_.num_channels_;
+ SetFrameData(1000, &frame_to_add_to);
+
+ AudioFrame frame_copy;
+ frame_copy.CopyFrom(frame_to_add_to);
+
+ ASSERT_TRUE(frame_.muted());
+ AudioFrameOperations::Add(frame_, &frame_to_add_to);
+ VerifyFramesAreEqual(frame_copy, frame_to_add_to);
+}
+
+TEST_F(AudioFrameOperationsTest, AddingTwoFramesProducesTheirSum) {
+ AudioFrame frame_to_add_to;
+ frame_to_add_to.samples_per_channel_ = frame_.samples_per_channel_;
+ frame_to_add_to.num_channels_ = frame_.num_channels_;
+ SetFrameData(1000, &frame_to_add_to);
+ SetFrameData(2000, &frame_);
+
+ AudioFrameOperations::Add(frame_, &frame_to_add_to);
+ SetFrameData(frame_.data()[0] + 1000, &frame_);
+ VerifyFramesAreEqual(frame_, frame_to_add_to);
+}
+
+} // namespace
+} // namespace webrtc
diff --git a/third_party/libwebrtc/audio/utility/channel_mixer.cc b/third_party/libwebrtc/audio/utility/channel_mixer.cc
new file mode 100644
index 0000000000..0f1e663873
--- /dev/null
+++ b/third_party/libwebrtc/audio/utility/channel_mixer.cc
@@ -0,0 +1,99 @@
+/*
+ * Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "audio/utility/channel_mixer.h"
+
+#include "audio/utility/channel_mixing_matrix.h"
+#include "rtc_base/checks.h"
+#include "rtc_base/logging.h"
+#include "rtc_base/numerics/safe_conversions.h"
+
+namespace webrtc {
+
+ChannelMixer::ChannelMixer(ChannelLayout input_layout,
+ ChannelLayout output_layout)
+ : input_layout_(input_layout),
+ output_layout_(output_layout),
+ input_channels_(ChannelLayoutToChannelCount(input_layout)),
+ output_channels_(ChannelLayoutToChannelCount(output_layout)) {
+ // Create the transformation matrix.
+ ChannelMixingMatrix matrix_builder(input_layout_, input_channels_,
+ output_layout_, output_channels_);
+ remapping_ = matrix_builder.CreateTransformationMatrix(&matrix_);
+}
+
+ChannelMixer::~ChannelMixer() = default;
+
+void ChannelMixer::Transform(AudioFrame* frame) {
+ RTC_DCHECK(frame);
+ RTC_DCHECK_EQ(matrix_[0].size(), static_cast<size_t>(input_channels_));
+ RTC_DCHECK_EQ(matrix_.size(), static_cast<size_t>(output_channels_));
+
+ // Leave the audio frame intact if the channel layouts for in and out are
+ // identical.
+ if (input_layout_ == output_layout_) {
+ return;
+ }
+
+ if (IsUpMixing()) {
+ RTC_CHECK_LE(frame->samples_per_channel() * output_channels_,
+ frame->max_16bit_samples());
+ }
+
+ // Only change the number of output channels if the audio frame is muted.
+ if (frame->muted()) {
+ frame->num_channels_ = output_channels_;
+ frame->channel_layout_ = output_layout_;
+ return;
+ }
+
+ const int16_t* in_audio = frame->data();
+
+ // Only allocate fresh memory at first access or if the required size has
+ // increased.
+ // TODO(henrika): we might be able to do downmixing in-place and thereby avoid
+ // extra memory allocation and a memcpy.
+ const size_t num_elements = frame->samples_per_channel() * output_channels_;
+ if (audio_vector_ == nullptr || num_elements > audio_vector_size_) {
+ audio_vector_.reset(new int16_t[num_elements]);
+ audio_vector_size_ = num_elements;
+ }
+ int16_t* out_audio = audio_vector_.get();
+
+ // Modify the number of channels by creating a weighted sum of input samples
+ // where the weights (scale factors) for each output sample are given by the
+ // transformation matrix.
+ for (size_t i = 0; i < frame->samples_per_channel(); i++) {
+ for (size_t output_ch = 0; output_ch < output_channels_; ++output_ch) {
+ float acc_value = 0.0f;
+ for (size_t input_ch = 0; input_ch < input_channels_; ++input_ch) {
+ const float scale = matrix_[output_ch][input_ch];
+ // Scale should always be positive.
+ RTC_DCHECK_GE(scale, 0);
+ // Each output sample is a weighted sum of input samples.
+ acc_value += scale * in_audio[i * input_channels_ + input_ch];
+ }
+ const size_t index = output_channels_ * i + output_ch;
+ RTC_CHECK_LE(index, audio_vector_size_);
+ out_audio[index] = rtc::saturated_cast<int16_t>(acc_value);
+ }
+ }
+
+ // Update channel information.
+ frame->num_channels_ = output_channels_;
+ frame->channel_layout_ = output_layout_;
+
+ // Copy the output result to the audio frame in `frame`.
+ memcpy(
+ frame->mutable_data(), out_audio,
+ sizeof(int16_t) * frame->samples_per_channel() * frame->num_channels());
+}
+
+} // namespace webrtc
diff --git a/third_party/libwebrtc/audio/utility/channel_mixer.h b/third_party/libwebrtc/audio/utility/channel_mixer.h
new file mode 100644
index 0000000000..2dea8eb45b
--- /dev/null
+++ b/third_party/libwebrtc/audio/utility/channel_mixer.h
@@ -0,0 +1,86 @@
+/*
+ * Copyright (c) 2019 The WebRTC project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef AUDIO_UTILITY_CHANNEL_MIXER_H_
+#define AUDIO_UTILITY_CHANNEL_MIXER_H_
+
+#include <stddef.h>
+#include <stdint.h>
+
+#include <memory>
+#include <vector>
+
+#include "api/audio/audio_frame.h"
+#include "api/audio/channel_layout.h"
+
+namespace webrtc {
+
+// ChannelMixer is for converting audio between channel layouts. The conversion
+// matrix is built upon construction and used during each Transform() call. The
+// algorithm works by generating a conversion matrix mapping each output channel
+// to list of input channels. The transform renders all of the output channels,
+// with each output channel rendered according to a weighted sum of the relevant
+// input channels as defined in the matrix.
+// This file is derived from Chromium's media/base/channel_mixer.h.
+class ChannelMixer {
+ public:
+ // To mix two channels into one and preserve loudness, we must apply
+ // (1 / sqrt(2)) gain to each.
+ static constexpr float kHalfPower = 0.707106781186547524401f;
+
+ ChannelMixer(ChannelLayout input_layout, ChannelLayout output_layout);
+ ~ChannelMixer();
+
+ // Transforms all input channels corresponding to the selected `input_layout`
+ // to the number of channels in the selected `output_layout`.
+ // Example usage (downmix from stereo to mono):
+ //
+ // ChannelMixer mixer(CHANNEL_LAYOUT_STEREO, CHANNEL_LAYOUT_MONO);
+ // AudioFrame frame;
+ // frame.samples_per_channel_ = 160;
+ // frame.num_channels_ = 2;
+ // EXPECT_EQ(2u, frame.channels());
+ // mixer.Transform(&frame);
+ // EXPECT_EQ(1u, frame.channels());
+ //
+ void Transform(AudioFrame* frame);
+
+ private:
+ bool IsUpMixing() const { return output_channels_ > input_channels_; }
+
+ // Selected channel layouts.
+ const ChannelLayout input_layout_;
+ const ChannelLayout output_layout_;
+
+ // Channel counts for input and output.
+ const size_t input_channels_;
+ const size_t output_channels_;
+
+ // 2D matrix of output channels to input channels.
+ std::vector<std::vector<float> > matrix_;
+
+ // 1D array used as temporary storage during the transformation.
+ std::unique_ptr<int16_t[]> audio_vector_;
+
+ // Number of elements allocated for `audio_vector_`.
+ size_t audio_vector_size_ = 0;
+
+ // Optimization case for when we can simply remap the input channels to output
+ // channels, i.e., when all scaling factors in `matrix_` equals 1.0.
+ bool remapping_;
+
+ // Delete the copy constructor and assignment operator.
+ ChannelMixer(const ChannelMixer& other) = delete;
+ ChannelMixer& operator=(const ChannelMixer& other) = delete;
+};
+
+} // namespace webrtc
+
+#endif // AUDIO_UTILITY_CHANNEL_MIXER_H_
diff --git a/third_party/libwebrtc/audio/utility/channel_mixer_unittest.cc b/third_party/libwebrtc/audio/utility/channel_mixer_unittest.cc
new file mode 100644
index 0000000000..94cb1ac7e3
--- /dev/null
+++ b/third_party/libwebrtc/audio/utility/channel_mixer_unittest.cc
@@ -0,0 +1,393 @@
+/*
+ * Copyright (c) 2019 The WebRTC project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "audio/utility/channel_mixer.h"
+
+#include <memory>
+
+#include "api/audio/audio_frame.h"
+#include "api/audio/channel_layout.h"
+#include "audio/utility/channel_mixing_matrix.h"
+#include "rtc_base/arraysize.h"
+#include "rtc_base/strings/string_builder.h"
+#include "test/gtest.h"
+
+namespace webrtc {
+
+namespace {
+
+constexpr uint32_t kTimestamp = 27;
+constexpr int kSampleRateHz = 16000;
+constexpr size_t kSamplesPerChannel = kSampleRateHz / 100;
+
+class ChannelMixerTest : public ::testing::Test {
+ protected:
+ ChannelMixerTest() {
+ // Use 10ms audio frames by default. Don't set values yet.
+ frame_.samples_per_channel_ = kSamplesPerChannel;
+ frame_.sample_rate_hz_ = kSampleRateHz;
+ EXPECT_TRUE(frame_.muted());
+ }
+
+ virtual ~ChannelMixerTest() {}
+
+ AudioFrame frame_;
+};
+
+void SetFrameData(int16_t data, AudioFrame* frame) {
+ int16_t* frame_data = frame->mutable_data();
+ for (size_t i = 0; i < frame->samples_per_channel() * frame->num_channels();
+ i++) {
+ frame_data[i] = data;
+ }
+}
+
+void SetMonoData(int16_t center, AudioFrame* frame) {
+ frame->num_channels_ = 1;
+ int16_t* frame_data = frame->mutable_data();
+ for (size_t i = 0; i < frame->samples_per_channel(); ++i) {
+ frame_data[i] = center;
+ }
+ EXPECT_FALSE(frame->muted());
+}
+
+void SetStereoData(int16_t left, int16_t right, AudioFrame* frame) {
+ ASSERT_LE(2 * frame->samples_per_channel(), frame->max_16bit_samples());
+ frame->num_channels_ = 2;
+ int16_t* frame_data = frame->mutable_data();
+ for (size_t i = 0; i < frame->samples_per_channel() * 2; i += 2) {
+ frame_data[i] = left;
+ frame_data[i + 1] = right;
+ }
+ EXPECT_FALSE(frame->muted());
+}
+
+void SetFiveOneData(int16_t front_left,
+ int16_t front_right,
+ int16_t center,
+ int16_t lfe,
+ int16_t side_left,
+ int16_t side_right,
+ AudioFrame* frame) {
+ ASSERT_LE(6 * frame->samples_per_channel(), frame->max_16bit_samples());
+ frame->num_channels_ = 6;
+ int16_t* frame_data = frame->mutable_data();
+ for (size_t i = 0; i < frame->samples_per_channel() * 6; i += 6) {
+ frame_data[i] = front_left;
+ frame_data[i + 1] = front_right;
+ frame_data[i + 2] = center;
+ frame_data[i + 3] = lfe;
+ frame_data[i + 4] = side_left;
+ frame_data[i + 5] = side_right;
+ }
+ EXPECT_FALSE(frame->muted());
+}
+
+void SetSevenOneData(int16_t front_left,
+ int16_t front_right,
+ int16_t center,
+ int16_t lfe,
+ int16_t side_left,
+ int16_t side_right,
+ int16_t back_left,
+ int16_t back_right,
+ AudioFrame* frame) {
+ ASSERT_LE(8 * frame->samples_per_channel(), frame->max_16bit_samples());
+ frame->num_channels_ = 8;
+ int16_t* frame_data = frame->mutable_data();
+ for (size_t i = 0; i < frame->samples_per_channel() * 8; i += 8) {
+ frame_data[i] = front_left;
+ frame_data[i + 1] = front_right;
+ frame_data[i + 2] = center;
+ frame_data[i + 3] = lfe;
+ frame_data[i + 4] = side_left;
+ frame_data[i + 5] = side_right;
+ frame_data[i + 6] = back_left;
+ frame_data[i + 7] = back_right;
+ }
+ EXPECT_FALSE(frame->muted());
+}
+
+bool AllSamplesEquals(int16_t sample, const AudioFrame* frame) {
+ const int16_t* frame_data = frame->data();
+ for (size_t i = 0; i < frame->samples_per_channel() * frame->num_channels();
+ i++) {
+ if (frame_data[i] != sample) {
+ return false;
+ }
+ }
+ return true;
+}
+
+void VerifyFramesAreEqual(const AudioFrame& frame1, const AudioFrame& frame2) {
+ EXPECT_EQ(frame1.num_channels(), frame2.num_channels());
+ EXPECT_EQ(frame1.samples_per_channel(), frame2.samples_per_channel());
+ const int16_t* frame1_data = frame1.data();
+ const int16_t* frame2_data = frame2.data();
+ for (size_t i = 0; i < frame1.samples_per_channel() * frame1.num_channels();
+ i++) {
+ EXPECT_EQ(frame1_data[i], frame2_data[i]);
+ }
+ EXPECT_EQ(frame1.muted(), frame2.muted());
+}
+
+} // namespace
+
+// Test all possible layout conversions can be constructed and mixed. Don't
+// care about the actual content, simply run through all mixing combinations
+// and ensure that nothing fails.
+TEST_F(ChannelMixerTest, ConstructAllPossibleLayouts) {
+ for (ChannelLayout input_layout = CHANNEL_LAYOUT_MONO;
+ input_layout <= CHANNEL_LAYOUT_MAX;
+ input_layout = static_cast<ChannelLayout>(input_layout + 1)) {
+ for (ChannelLayout output_layout = CHANNEL_LAYOUT_MONO;
+ output_layout <= CHANNEL_LAYOUT_MAX;
+ output_layout = static_cast<ChannelLayout>(output_layout + 1)) {
+ // DISCRETE, BITSTREAM can't be tested here based on the current approach.
+ // CHANNEL_LAYOUT_STEREO_AND_KEYBOARD_MIC is not mixable.
+ // Stereo down mix should never be the output layout.
+ if (input_layout == CHANNEL_LAYOUT_BITSTREAM ||
+ input_layout == CHANNEL_LAYOUT_DISCRETE ||
+ input_layout == CHANNEL_LAYOUT_STEREO_AND_KEYBOARD_MIC ||
+ output_layout == CHANNEL_LAYOUT_BITSTREAM ||
+ output_layout == CHANNEL_LAYOUT_DISCRETE ||
+ output_layout == CHANNEL_LAYOUT_STEREO_AND_KEYBOARD_MIC ||
+ output_layout == CHANNEL_LAYOUT_STEREO_DOWNMIX) {
+ continue;
+ }
+
+ rtc::StringBuilder ss;
+ ss << "Input Layout: " << input_layout
+ << ", Output Layout: " << output_layout;
+ SCOPED_TRACE(ss.str());
+ ChannelMixer mixer(input_layout, output_layout);
+
+ frame_.UpdateFrame(kTimestamp, nullptr, kSamplesPerChannel, kSampleRateHz,
+ AudioFrame::kNormalSpeech, AudioFrame::kVadActive,
+ ChannelLayoutToChannelCount(input_layout));
+ EXPECT_TRUE(frame_.muted());
+ mixer.Transform(&frame_);
+ }
+ }
+}
+
+// Ensure that the audio frame is untouched when input and output channel
+// layouts are identical, i.e., the transformation should have no effect.
+// Exclude invalid mixing combinations.
+TEST_F(ChannelMixerTest, NoMixingForIdenticalChannelLayouts) {
+ for (ChannelLayout input_layout = CHANNEL_LAYOUT_MONO;
+ input_layout <= CHANNEL_LAYOUT_MAX;
+ input_layout = static_cast<ChannelLayout>(input_layout + 1)) {
+ for (ChannelLayout output_layout = CHANNEL_LAYOUT_MONO;
+ output_layout <= CHANNEL_LAYOUT_MAX;
+ output_layout = static_cast<ChannelLayout>(output_layout + 1)) {
+ if (input_layout != output_layout ||
+ input_layout == CHANNEL_LAYOUT_BITSTREAM ||
+ input_layout == CHANNEL_LAYOUT_DISCRETE ||
+ input_layout == CHANNEL_LAYOUT_STEREO_AND_KEYBOARD_MIC ||
+ output_layout == CHANNEL_LAYOUT_STEREO_DOWNMIX) {
+ continue;
+ }
+ ChannelMixer mixer(input_layout, output_layout);
+ frame_.num_channels_ = ChannelLayoutToChannelCount(input_layout);
+ SetFrameData(99, &frame_);
+ mixer.Transform(&frame_);
+ EXPECT_EQ(ChannelLayoutToChannelCount(input_layout),
+ static_cast<int>(frame_.num_channels()));
+ EXPECT_TRUE(AllSamplesEquals(99, &frame_));
+ }
+ }
+}
+
+TEST_F(ChannelMixerTest, StereoToMono) {
+ ChannelMixer mixer(CHANNEL_LAYOUT_STEREO, CHANNEL_LAYOUT_MONO);
+ //
+ // Input: stereo
+ // LEFT RIGHT
+ // Output: mono CENTER 0.5 0.5
+ //
+ SetStereoData(7, 3, &frame_);
+ EXPECT_EQ(2u, frame_.num_channels());
+ mixer.Transform(&frame_);
+ EXPECT_EQ(1u, frame_.num_channels());
+ EXPECT_EQ(CHANNEL_LAYOUT_MONO, frame_.channel_layout());
+
+ AudioFrame mono_frame;
+ mono_frame.samples_per_channel_ = frame_.samples_per_channel();
+ SetMonoData(5, &mono_frame);
+ VerifyFramesAreEqual(mono_frame, frame_);
+
+ SetStereoData(-32768, -32768, &frame_);
+ EXPECT_EQ(2u, frame_.num_channels());
+ mixer.Transform(&frame_);
+ EXPECT_EQ(1u, frame_.num_channels());
+ EXPECT_EQ(CHANNEL_LAYOUT_MONO, frame_.channel_layout());
+ SetMonoData(-32768, &mono_frame);
+ VerifyFramesAreEqual(mono_frame, frame_);
+}
+
+TEST_F(ChannelMixerTest, StereoToMonoMuted) {
+ ASSERT_TRUE(frame_.muted());
+ ChannelMixer mixer(CHANNEL_LAYOUT_STEREO, CHANNEL_LAYOUT_MONO);
+ mixer.Transform(&frame_);
+ EXPECT_EQ(1u, frame_.num_channels());
+ EXPECT_EQ(CHANNEL_LAYOUT_MONO, frame_.channel_layout());
+ EXPECT_TRUE(frame_.muted());
+}
+
+TEST_F(ChannelMixerTest, FiveOneToSevenOneMuted) {
+ ASSERT_TRUE(frame_.muted());
+ ChannelMixer mixer(CHANNEL_LAYOUT_5_1, CHANNEL_LAYOUT_7_1);
+ mixer.Transform(&frame_);
+ EXPECT_EQ(8u, frame_.num_channels());
+ EXPECT_EQ(CHANNEL_LAYOUT_7_1, frame_.channel_layout());
+ EXPECT_TRUE(frame_.muted());
+}
+
+TEST_F(ChannelMixerTest, FiveOneToMono) {
+ ChannelMixer mixer(CHANNEL_LAYOUT_5_1, CHANNEL_LAYOUT_MONO);
+ //
+ // Input: 5.1
+ // LEFT RIGHT CENTER LFE SIDE_LEFT SIDE_RIGHT
+ // Output: mono CENTER 0.707 0.707 1 0.707 0.707 0.707
+ //
+ // a = [10, 20, 15, 2, 5, 5]
+ // b = [1/sqrt(2), 1/sqrt(2), 1.0, 1/sqrt(2), 1/sqrt(2), 1/sqrt(2)] =>
+ // a * b (dot product) = 44.69848480983499,
+ // which is truncated into 44 using 16 bit representation.
+ //
+ SetFiveOneData(10, 20, 15, 2, 5, 5, &frame_);
+ EXPECT_EQ(6u, frame_.num_channels());
+ mixer.Transform(&frame_);
+ EXPECT_EQ(1u, frame_.num_channels());
+ EXPECT_EQ(CHANNEL_LAYOUT_MONO, frame_.channel_layout());
+
+ AudioFrame mono_frame;
+ mono_frame.samples_per_channel_ = frame_.samples_per_channel();
+ SetMonoData(44, &mono_frame);
+ VerifyFramesAreEqual(mono_frame, frame_);
+
+ SetFiveOneData(-32768, -32768, -32768, -32768, -32768, -32768, &frame_);
+ EXPECT_EQ(6u, frame_.num_channels());
+ mixer.Transform(&frame_);
+ EXPECT_EQ(1u, frame_.num_channels());
+ EXPECT_EQ(CHANNEL_LAYOUT_MONO, frame_.channel_layout());
+ SetMonoData(-32768, &mono_frame);
+ VerifyFramesAreEqual(mono_frame, frame_);
+}
+
+TEST_F(ChannelMixerTest, FiveOneToSevenOne) {
+ ChannelMixer mixer(CHANNEL_LAYOUT_5_1, CHANNEL_LAYOUT_7_1);
+ //
+ // Input: 5.1
+ // LEFT RIGHT CENTER LFE SIDE_LEFT SIDE_RIGHT
+ // Output: 7.1 LEFT 1 0 0 0 0 0
+ // RIGHT 0 1 0 0 0 0
+ // CENTER 0 0 1 0 0 0
+ // LFE 0 0 0 1 0 0
+ // SIDE_LEFT 0 0 0 0 1 0
+ // SIDE_RIGHT 0 0 0 0 0 1
+ // BACK_LEFT 0 0 0 0 0 0
+ // BACK_RIGHT 0 0 0 0 0 0
+ //
+ SetFiveOneData(10, 20, 15, 2, 5, 5, &frame_);
+ EXPECT_EQ(6u, frame_.num_channels());
+ mixer.Transform(&frame_);
+ EXPECT_EQ(8u, frame_.num_channels());
+ EXPECT_EQ(CHANNEL_LAYOUT_7_1, frame_.channel_layout());
+
+ AudioFrame seven_one_frame;
+ seven_one_frame.samples_per_channel_ = frame_.samples_per_channel();
+ SetSevenOneData(10, 20, 15, 2, 5, 5, 0, 0, &seven_one_frame);
+ VerifyFramesAreEqual(seven_one_frame, frame_);
+
+ SetFiveOneData(-32768, 32767, -32768, 32767, -32768, 32767, &frame_);
+ EXPECT_EQ(6u, frame_.num_channels());
+ mixer.Transform(&frame_);
+ EXPECT_EQ(8u, frame_.num_channels());
+ EXPECT_EQ(CHANNEL_LAYOUT_7_1, frame_.channel_layout());
+ SetSevenOneData(-32768, 32767, -32768, 32767, -32768, 32767, 0, 0,
+ &seven_one_frame);
+ VerifyFramesAreEqual(seven_one_frame, frame_);
+}
+
+TEST_F(ChannelMixerTest, FiveOneBackToStereo) {
+ ChannelMixer mixer(CHANNEL_LAYOUT_5_1_BACK, CHANNEL_LAYOUT_STEREO);
+ //
+ // Input: 5.1
+ // LEFT RIGHT CENTER LFE BACK_LEFT BACK_RIGHT
+ // Output: stereo LEFT 1 0 0.707 0.707 0.707 0
+ // RIGHT 0 1 0.707 0.707 0 0.707
+ //
+ SetFiveOneData(20, 30, 15, 2, 5, 5, &frame_);
+ EXPECT_EQ(6u, frame_.num_channels());
+ mixer.Transform(&frame_);
+ EXPECT_EQ(2u, frame_.num_channels());
+ EXPECT_EQ(CHANNEL_LAYOUT_STEREO, frame_.channel_layout());
+
+ AudioFrame stereo_frame;
+ stereo_frame.samples_per_channel_ = frame_.samples_per_channel();
+ SetStereoData(35, 45, &stereo_frame);
+ VerifyFramesAreEqual(stereo_frame, frame_);
+
+ SetFiveOneData(-32768, -32768, -32768, -32768, -32768, -32768, &frame_);
+ EXPECT_EQ(6u, frame_.num_channels());
+ mixer.Transform(&frame_);
+ EXPECT_EQ(2u, frame_.num_channels());
+ EXPECT_EQ(CHANNEL_LAYOUT_STEREO, frame_.channel_layout());
+ SetStereoData(-32768, -32768, &stereo_frame);
+ VerifyFramesAreEqual(stereo_frame, frame_);
+}
+
+TEST_F(ChannelMixerTest, MonoToStereo) {
+ ChannelMixer mixer(CHANNEL_LAYOUT_MONO, CHANNEL_LAYOUT_STEREO);
+ //
+ // Input: mono
+ // CENTER
+ // Output: stereo LEFT 1
+ // RIGHT 1
+ //
+ SetMonoData(44, &frame_);
+ EXPECT_EQ(1u, frame_.num_channels());
+ mixer.Transform(&frame_);
+ EXPECT_EQ(2u, frame_.num_channels());
+ EXPECT_EQ(CHANNEL_LAYOUT_STEREO, frame_.channel_layout());
+
+ AudioFrame stereo_frame;
+ stereo_frame.samples_per_channel_ = frame_.samples_per_channel();
+ SetStereoData(44, 44, &stereo_frame);
+ VerifyFramesAreEqual(stereo_frame, frame_);
+}
+
+TEST_F(ChannelMixerTest, StereoToFiveOne) {
+ ChannelMixer mixer(CHANNEL_LAYOUT_STEREO, CHANNEL_LAYOUT_5_1);
+ //
+ // Input: Stereo
+ // LEFT RIGHT
+ // Output: 5.1 LEFT 1 0
+ // RIGHT 0 1
+ // CENTER 0 0
+ // LFE 0 0
+ // SIDE_LEFT 0 0
+ // SIDE_RIGHT 0 0
+ //
+ SetStereoData(50, 60, &frame_);
+ EXPECT_EQ(2u, frame_.num_channels());
+ mixer.Transform(&frame_);
+ EXPECT_EQ(6u, frame_.num_channels());
+ EXPECT_EQ(CHANNEL_LAYOUT_5_1, frame_.channel_layout());
+
+ AudioFrame five_one_frame;
+ five_one_frame.samples_per_channel_ = frame_.samples_per_channel();
+ SetFiveOneData(50, 60, 0, 0, 0, 0, &five_one_frame);
+ VerifyFramesAreEqual(five_one_frame, frame_);
+}
+
+} // namespace webrtc
diff --git a/third_party/libwebrtc/audio/utility/channel_mixing_matrix.cc b/third_party/libwebrtc/audio/utility/channel_mixing_matrix.cc
new file mode 100644
index 0000000000..1244653f63
--- /dev/null
+++ b/third_party/libwebrtc/audio/utility/channel_mixing_matrix.cc
@@ -0,0 +1,333 @@
+/*
+ * Copyright (c) 2019 The WebRTC project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "audio/utility/channel_mixing_matrix.h"
+
+#include <stddef.h>
+
+#include <algorithm>
+
+#include "audio/utility/channel_mixer.h"
+#include "rtc_base/checks.h"
+#include "rtc_base/logging.h"
+#include "system_wrappers/include/field_trial.h"
+
+namespace webrtc {
+
+namespace {
+
+// Selects the default usage of VoIP channel mapping adjustments.
+bool UseChannelMappingAdjustmentsByDefault() {
+ return !field_trial::IsEnabled(
+ "WebRTC-VoIPChannelRemixingAdjustmentKillSwitch");
+}
+
+} // namespace
+
+static void ValidateLayout(ChannelLayout layout) {
+ RTC_CHECK_NE(layout, CHANNEL_LAYOUT_NONE);
+ RTC_CHECK_LE(layout, CHANNEL_LAYOUT_MAX);
+ RTC_CHECK_NE(layout, CHANNEL_LAYOUT_UNSUPPORTED);
+ RTC_CHECK_NE(layout, CHANNEL_LAYOUT_DISCRETE);
+ RTC_CHECK_NE(layout, CHANNEL_LAYOUT_STEREO_AND_KEYBOARD_MIC);
+
+ // Verify there's at least one channel. Should always be true here by virtue
+ // of not being one of the invalid layouts, but lets double check to be sure.
+ int channel_count = ChannelLayoutToChannelCount(layout);
+ RTC_DCHECK_GT(channel_count, 0);
+
+ // If we have more than one channel, verify a symmetric layout for sanity.
+ // The unit test will verify all possible layouts, so this can be a DCHECK.
+ // Symmetry allows simplifying the matrix building code by allowing us to
+ // assume that if one channel of a pair exists, the other will too.
+ if (channel_count > 1) {
+ // Assert that LEFT exists if and only if RIGHT exists, and so on.
+ RTC_DCHECK_EQ(ChannelOrder(layout, LEFT) >= 0,
+ ChannelOrder(layout, RIGHT) >= 0);
+ RTC_DCHECK_EQ(ChannelOrder(layout, SIDE_LEFT) >= 0,
+ ChannelOrder(layout, SIDE_RIGHT) >= 0);
+ RTC_DCHECK_EQ(ChannelOrder(layout, BACK_LEFT) >= 0,
+ ChannelOrder(layout, BACK_RIGHT) >= 0);
+ RTC_DCHECK_EQ(ChannelOrder(layout, LEFT_OF_CENTER) >= 0,
+ ChannelOrder(layout, RIGHT_OF_CENTER) >= 0);
+ } else {
+ RTC_DCHECK_EQ(layout, CHANNEL_LAYOUT_MONO);
+ }
+}
+
+ChannelMixingMatrix::ChannelMixingMatrix(ChannelLayout input_layout,
+ int input_channels,
+ ChannelLayout output_layout,
+ int output_channels)
+ : use_voip_channel_mapping_adjustments_(
+ UseChannelMappingAdjustmentsByDefault()),
+ input_layout_(input_layout),
+ input_channels_(input_channels),
+ output_layout_(output_layout),
+ output_channels_(output_channels) {
+ // Stereo down mix should never be the output layout.
+ RTC_CHECK_NE(output_layout, CHANNEL_LAYOUT_STEREO_DOWNMIX);
+
+ // Verify that the layouts are supported
+ if (input_layout != CHANNEL_LAYOUT_DISCRETE)
+ ValidateLayout(input_layout);
+ if (output_layout != CHANNEL_LAYOUT_DISCRETE)
+ ValidateLayout(output_layout);
+
+ // Special case for 5.0, 5.1 with back channels when upmixed to 7.0, 7.1,
+ // which should map the back LR to side LR.
+ if (input_layout_ == CHANNEL_LAYOUT_5_0_BACK &&
+ output_layout_ == CHANNEL_LAYOUT_7_0) {
+ input_layout_ = CHANNEL_LAYOUT_5_0;
+ } else if (input_layout_ == CHANNEL_LAYOUT_5_1_BACK &&
+ output_layout_ == CHANNEL_LAYOUT_7_1) {
+ input_layout_ = CHANNEL_LAYOUT_5_1;
+ }
+}
+
+ChannelMixingMatrix::~ChannelMixingMatrix() = default;
+
+bool ChannelMixingMatrix::CreateTransformationMatrix(
+ std::vector<std::vector<float>>* matrix) {
+ matrix_ = matrix;
+
+ // Size out the initial matrix.
+ matrix_->reserve(output_channels_);
+ for (int output_ch = 0; output_ch < output_channels_; ++output_ch)
+ matrix_->push_back(std::vector<float>(input_channels_, 0));
+
+ // First check for discrete case.
+ if (input_layout_ == CHANNEL_LAYOUT_DISCRETE ||
+ output_layout_ == CHANNEL_LAYOUT_DISCRETE) {
+ // If the number of input channels is more than output channels, then
+ // copy as many as we can then drop the remaining input channels.
+ // If the number of input channels is less than output channels, then
+ // copy them all, then zero out the remaining output channels.
+ int passthrough_channels = std::min(input_channels_, output_channels_);
+ for (int i = 0; i < passthrough_channels; ++i)
+ (*matrix_)[i][i] = 1;
+
+ return true;
+ }
+
+ // If specified, use adjusted channel mapping for the VoIP scenario.
+ if (use_voip_channel_mapping_adjustments_ &&
+ input_layout_ == CHANNEL_LAYOUT_MONO &&
+ ChannelLayoutToChannelCount(output_layout_) >= 2) {
+ // Only place the mono input in the front left and right channels.
+ (*matrix_)[0][0] = 1.f;
+ (*matrix_)[1][0] = 1.f;
+
+ for (size_t output_ch = 2; output_ch < matrix_->size(); ++output_ch) {
+ (*matrix_)[output_ch][0] = 0.f;
+ }
+ return true;
+ }
+
+ // Route matching channels and figure out which ones aren't accounted for.
+ for (Channels ch = LEFT; ch < CHANNELS_MAX + 1;
+ ch = static_cast<Channels>(ch + 1)) {
+ int input_ch_index = ChannelOrder(input_layout_, ch);
+ if (input_ch_index < 0)
+ continue;
+
+ int output_ch_index = ChannelOrder(output_layout_, ch);
+ if (output_ch_index < 0) {
+ unaccounted_inputs_.push_back(ch);
+ continue;
+ }
+
+ RTC_DCHECK_LT(static_cast<size_t>(output_ch_index), matrix_->size());
+ RTC_DCHECK_LT(static_cast<size_t>(input_ch_index),
+ (*matrix_)[output_ch_index].size());
+ (*matrix_)[output_ch_index][input_ch_index] = 1;
+ }
+
+ // If all input channels are accounted for, there's nothing left to do.
+ if (unaccounted_inputs_.empty()) {
+ // Since all output channels map directly to inputs we can optimize.
+ return true;
+ }
+
+ // Mix front LR into center.
+ if (IsUnaccounted(LEFT)) {
+ // When down mixing to mono from stereo, we need to be careful of full scale
+ // stereo mixes. Scaling by 1 / sqrt(2) here will likely lead to clipping
+ // so we use 1 / 2 instead.
+ float scale =
+ (output_layout_ == CHANNEL_LAYOUT_MONO && input_channels_ == 2)
+ ? 0.5
+ : ChannelMixer::kHalfPower;
+ Mix(LEFT, CENTER, scale);
+ Mix(RIGHT, CENTER, scale);
+ }
+
+ // Mix center into front LR.
+ if (IsUnaccounted(CENTER)) {
+ // When up mixing from mono, just do a copy to front LR.
+ float scale =
+ (input_layout_ == CHANNEL_LAYOUT_MONO) ? 1 : ChannelMixer::kHalfPower;
+ MixWithoutAccounting(CENTER, LEFT, scale);
+ Mix(CENTER, RIGHT, scale);
+ }
+
+ // Mix back LR into: side LR || back center || front LR || front center.
+ if (IsUnaccounted(BACK_LEFT)) {
+ if (HasOutputChannel(SIDE_LEFT)) {
+ // If the input has side LR, mix back LR into side LR, but instead if the
+ // input doesn't have side LR (but output does) copy back LR to side LR.
+ float scale = HasInputChannel(SIDE_LEFT) ? ChannelMixer::kHalfPower : 1;
+ Mix(BACK_LEFT, SIDE_LEFT, scale);
+ Mix(BACK_RIGHT, SIDE_RIGHT, scale);
+ } else if (HasOutputChannel(BACK_CENTER)) {
+ // Mix back LR into back center.
+ Mix(BACK_LEFT, BACK_CENTER, ChannelMixer::kHalfPower);
+ Mix(BACK_RIGHT, BACK_CENTER, ChannelMixer::kHalfPower);
+ } else if (output_layout_ > CHANNEL_LAYOUT_MONO) {
+ // Mix back LR into front LR.
+ Mix(BACK_LEFT, LEFT, ChannelMixer::kHalfPower);
+ Mix(BACK_RIGHT, RIGHT, ChannelMixer::kHalfPower);
+ } else {
+ // Mix back LR into front center.
+ Mix(BACK_LEFT, CENTER, ChannelMixer::kHalfPower);
+ Mix(BACK_RIGHT, CENTER, ChannelMixer::kHalfPower);
+ }
+ }
+
+ // Mix side LR into: back LR || back center || front LR || front center.
+ if (IsUnaccounted(SIDE_LEFT)) {
+ if (HasOutputChannel(BACK_LEFT)) {
+ // If the input has back LR, mix side LR into back LR, but instead if the
+ // input doesn't have back LR (but output does) copy side LR to back LR.
+ float scale = HasInputChannel(BACK_LEFT) ? ChannelMixer::kHalfPower : 1;
+ Mix(SIDE_LEFT, BACK_LEFT, scale);
+ Mix(SIDE_RIGHT, BACK_RIGHT, scale);
+ } else if (HasOutputChannel(BACK_CENTER)) {
+ // Mix side LR into back center.
+ Mix(SIDE_LEFT, BACK_CENTER, ChannelMixer::kHalfPower);
+ Mix(SIDE_RIGHT, BACK_CENTER, ChannelMixer::kHalfPower);
+ } else if (output_layout_ > CHANNEL_LAYOUT_MONO) {
+ // Mix side LR into front LR.
+ Mix(SIDE_LEFT, LEFT, ChannelMixer::kHalfPower);
+ Mix(SIDE_RIGHT, RIGHT, ChannelMixer::kHalfPower);
+ } else {
+ // Mix side LR into front center.
+ Mix(SIDE_LEFT, CENTER, ChannelMixer::kHalfPower);
+ Mix(SIDE_RIGHT, CENTER, ChannelMixer::kHalfPower);
+ }
+ }
+
+ // Mix back center into: back LR || side LR || front LR || front center.
+ if (IsUnaccounted(BACK_CENTER)) {
+ if (HasOutputChannel(BACK_LEFT)) {
+ // Mix back center into back LR.
+ MixWithoutAccounting(BACK_CENTER, BACK_LEFT, ChannelMixer::kHalfPower);
+ Mix(BACK_CENTER, BACK_RIGHT, ChannelMixer::kHalfPower);
+ } else if (HasOutputChannel(SIDE_LEFT)) {
+ // Mix back center into side LR.
+ MixWithoutAccounting(BACK_CENTER, SIDE_LEFT, ChannelMixer::kHalfPower);
+ Mix(BACK_CENTER, SIDE_RIGHT, ChannelMixer::kHalfPower);
+ } else if (output_layout_ > CHANNEL_LAYOUT_MONO) {
+ // Mix back center into front LR.
+ // TODO(dalecurtis): Not sure about these values?
+ MixWithoutAccounting(BACK_CENTER, LEFT, ChannelMixer::kHalfPower);
+ Mix(BACK_CENTER, RIGHT, ChannelMixer::kHalfPower);
+ } else {
+ // Mix back center into front center.
+ // TODO(dalecurtis): Not sure about these values?
+ Mix(BACK_CENTER, CENTER, ChannelMixer::kHalfPower);
+ }
+ }
+
+ // Mix LR of center into: front LR || front center.
+ if (IsUnaccounted(LEFT_OF_CENTER)) {
+ if (HasOutputChannel(LEFT)) {
+ // Mix LR of center into front LR.
+ Mix(LEFT_OF_CENTER, LEFT, ChannelMixer::kHalfPower);
+ Mix(RIGHT_OF_CENTER, RIGHT, ChannelMixer::kHalfPower);
+ } else {
+ // Mix LR of center into front center.
+ Mix(LEFT_OF_CENTER, CENTER, ChannelMixer::kHalfPower);
+ Mix(RIGHT_OF_CENTER, CENTER, ChannelMixer::kHalfPower);
+ }
+ }
+
+ // Mix LFE into: front center || front LR.
+ if (IsUnaccounted(LFE)) {
+ if (!HasOutputChannel(CENTER)) {
+ // Mix LFE into front LR.
+ MixWithoutAccounting(LFE, LEFT, ChannelMixer::kHalfPower);
+ Mix(LFE, RIGHT, ChannelMixer::kHalfPower);
+ } else {
+ // Mix LFE into front center.
+ Mix(LFE, CENTER, ChannelMixer::kHalfPower);
+ }
+ }
+
+ // All channels should now be accounted for.
+ RTC_DCHECK(unaccounted_inputs_.empty());
+
+ // See if the output `matrix_` is simply a remapping matrix. If each input
+ // channel maps to a single output channel we can simply remap. Doing this
+ // programmatically is less fragile than logic checks on channel mappings.
+ for (int output_ch = 0; output_ch < output_channels_; ++output_ch) {
+ int input_mappings = 0;
+ for (int input_ch = 0; input_ch < input_channels_; ++input_ch) {
+ // We can only remap if each row contains a single scale of 1. I.e., each
+ // output channel is mapped from a single unscaled input channel.
+ if ((*matrix_)[output_ch][input_ch] != 1 || ++input_mappings > 1)
+ return false;
+ }
+ }
+
+ // If we've gotten here, `matrix_` is simply a remapping.
+ return true;
+}
+
+void ChannelMixingMatrix::AccountFor(Channels ch) {
+ unaccounted_inputs_.erase(
+ std::find(unaccounted_inputs_.begin(), unaccounted_inputs_.end(), ch));
+}
+
+bool ChannelMixingMatrix::IsUnaccounted(Channels ch) const {
+ return std::find(unaccounted_inputs_.begin(), unaccounted_inputs_.end(),
+ ch) != unaccounted_inputs_.end();
+}
+
+bool ChannelMixingMatrix::HasInputChannel(Channels ch) const {
+ return ChannelOrder(input_layout_, ch) >= 0;
+}
+
+bool ChannelMixingMatrix::HasOutputChannel(Channels ch) const {
+ return ChannelOrder(output_layout_, ch) >= 0;
+}
+
+void ChannelMixingMatrix::Mix(Channels input_ch,
+ Channels output_ch,
+ float scale) {
+ MixWithoutAccounting(input_ch, output_ch, scale);
+ AccountFor(input_ch);
+}
+
+void ChannelMixingMatrix::MixWithoutAccounting(Channels input_ch,
+ Channels output_ch,
+ float scale) {
+ int input_ch_index = ChannelOrder(input_layout_, input_ch);
+ int output_ch_index = ChannelOrder(output_layout_, output_ch);
+
+ RTC_DCHECK(IsUnaccounted(input_ch));
+ RTC_DCHECK_GE(input_ch_index, 0);
+ RTC_DCHECK_GE(output_ch_index, 0);
+
+ RTC_DCHECK_EQ((*matrix_)[output_ch_index][input_ch_index], 0);
+ (*matrix_)[output_ch_index][input_ch_index] = scale;
+}
+
+} // namespace webrtc
diff --git a/third_party/libwebrtc/audio/utility/channel_mixing_matrix.h b/third_party/libwebrtc/audio/utility/channel_mixing_matrix.h
new file mode 100644
index 0000000000..ee00860846
--- /dev/null
+++ b/third_party/libwebrtc/audio/utility/channel_mixing_matrix.h
@@ -0,0 +1,76 @@
+/*
+ * Copyright (c) 2019 The WebRTC project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef AUDIO_UTILITY_CHANNEL_MIXING_MATRIX_H_
+#define AUDIO_UTILITY_CHANNEL_MIXING_MATRIX_H_
+
+#include <vector>
+
+#include "api/audio/channel_layout.h"
+
+namespace webrtc {
+
+class ChannelMixingMatrix {
+ public:
+ ChannelMixingMatrix(ChannelLayout input_layout,
+ int input_channels,
+ ChannelLayout output_layout,
+ int output_channels);
+
+ ~ChannelMixingMatrix();
+
+ // Create the transformation matrix of input channels to output channels.
+ // Updates the empty matrix with the transformation, and returns true
+ // if the transformation is just a remapping of channels (no mixing).
+ // The size of `matrix` is `output_channels` x `input_channels`, i.e., the
+ // number of rows equals the number of output channels and the number of
+ // columns corresponds to the number of input channels.
+ // This file is derived from Chromium's media/base/channel_mixing_matrix.h.
+ bool CreateTransformationMatrix(std::vector<std::vector<float>>* matrix);
+
+ private:
+ const bool use_voip_channel_mapping_adjustments_;
+
+ // Result transformation of input channels to output channels
+ std::vector<std::vector<float>>* matrix_;
+
+ // Input and output channel layout provided during construction.
+ ChannelLayout input_layout_;
+ int input_channels_;
+ ChannelLayout output_layout_;
+ int output_channels_;
+
+ // Helper variable for tracking which inputs are currently unaccounted,
+ // should be empty after construction completes.
+ std::vector<Channels> unaccounted_inputs_;
+
+ // Helper methods for managing unaccounted input channels.
+ void AccountFor(Channels ch);
+ bool IsUnaccounted(Channels ch) const;
+
+ // Helper methods for checking if `ch` exists in either `input_layout_` or
+ // `output_layout_` respectively.
+ bool HasInputChannel(Channels ch) const;
+ bool HasOutputChannel(Channels ch) const;
+
+ // Helper methods for updating `matrix_` with the proper value for
+ // mixing `input_ch` into `output_ch`. MixWithoutAccounting() does not
+ // remove the channel from `unaccounted_inputs_`.
+ void Mix(Channels input_ch, Channels output_ch, float scale);
+ void MixWithoutAccounting(Channels input_ch, Channels output_ch, float scale);
+
+ // Delete the copy constructor and assignment operator.
+ ChannelMixingMatrix(const ChannelMixingMatrix& other) = delete;
+ ChannelMixingMatrix& operator=(const ChannelMixingMatrix& other) = delete;
+};
+
+} // namespace webrtc
+
+#endif // AUDIO_UTILITY_CHANNEL_MIXING_MATRIX_H_
diff --git a/third_party/libwebrtc/audio/utility/channel_mixing_matrix_unittest.cc b/third_party/libwebrtc/audio/utility/channel_mixing_matrix_unittest.cc
new file mode 100644
index 0000000000..a4efb4fd38
--- /dev/null
+++ b/third_party/libwebrtc/audio/utility/channel_mixing_matrix_unittest.cc
@@ -0,0 +1,476 @@
+/*
+ * Copyright (c) 2019 The WebRTC project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "audio/utility/channel_mixing_matrix.h"
+
+#include <stddef.h>
+
+#include "audio/utility/channel_mixer.h"
+#include "rtc_base/arraysize.h"
+#include "rtc_base/logging.h"
+#include "rtc_base/strings/string_builder.h"
+#include "test/field_trial.h"
+#include "test/gtest.h"
+
+namespace webrtc {
+
+// Test all possible layout conversions can be constructed and mixed.
+// Also ensure that the channel matrix fulfill certain conditions when remapping
+// is supported.
+TEST(ChannelMixingMatrixTest, ConstructAllPossibleLayouts) {
+ for (ChannelLayout input_layout = CHANNEL_LAYOUT_MONO;
+ input_layout <= CHANNEL_LAYOUT_MAX;
+ input_layout = static_cast<ChannelLayout>(input_layout + 1)) {
+ for (ChannelLayout output_layout = CHANNEL_LAYOUT_MONO;
+ output_layout <= CHANNEL_LAYOUT_MAX;
+ output_layout = static_cast<ChannelLayout>(output_layout + 1)) {
+ // DISCRETE, BITSTREAM can't be tested here based on the current approach.
+ // CHANNEL_LAYOUT_STEREO_AND_KEYBOARD_MIC is not mixable.
+ // Stereo down mix should never be the output layout.
+ if (input_layout == CHANNEL_LAYOUT_BITSTREAM ||
+ input_layout == CHANNEL_LAYOUT_DISCRETE ||
+ input_layout == CHANNEL_LAYOUT_STEREO_AND_KEYBOARD_MIC ||
+ output_layout == CHANNEL_LAYOUT_BITSTREAM ||
+ output_layout == CHANNEL_LAYOUT_DISCRETE ||
+ output_layout == CHANNEL_LAYOUT_STEREO_AND_KEYBOARD_MIC ||
+ output_layout == CHANNEL_LAYOUT_STEREO_DOWNMIX) {
+ continue;
+ }
+
+ rtc::StringBuilder ss;
+ ss << "Input Layout: " << input_layout
+ << ", Output Layout: " << output_layout;
+ SCOPED_TRACE(ss.str());
+ ChannelMixingMatrix matrix_builder(
+ input_layout, ChannelLayoutToChannelCount(input_layout),
+ output_layout, ChannelLayoutToChannelCount(output_layout));
+ const int input_channels = ChannelLayoutToChannelCount(input_layout);
+ const int output_channels = ChannelLayoutToChannelCount(output_layout);
+ std::vector<std::vector<float>> matrix;
+ bool remapping = matrix_builder.CreateTransformationMatrix(&matrix);
+
+ if (remapping) {
+ // Also ensure that (when remapping can take place), a maximum of one
+ // input channel is included per output. This knowledge will simplify
+ // the channel mixing algorithm since it allows us to find the only
+ // scale factor which equals 1.0 and copy that input to its
+ // corresponding output. If no such factor can be found, the
+ // corresponding output can be set to zero.
+ for (int i = 0; i < output_channels; i++) {
+ EXPECT_EQ(static_cast<size_t>(input_channels), matrix[i].size());
+ int num_input_channels_accounted_for_per_output = 0;
+ for (int j = 0; j < input_channels; j++) {
+ float scale = matrix[i][j];
+ if (scale > 0) {
+ EXPECT_EQ(scale, 1.0f);
+ num_input_channels_accounted_for_per_output++;
+ }
+ }
+ // Each output channel shall contain contribution from one or less
+ // input channels.
+ EXPECT_LE(num_input_channels_accounted_for_per_output, 1);
+ }
+ }
+ }
+ }
+}
+
+// Verify channels are mixed and scaled correctly.
+TEST(ChannelMixingMatrixTest, StereoToMono) {
+ ChannelLayout input_layout = CHANNEL_LAYOUT_STEREO;
+ ChannelLayout output_layout = CHANNEL_LAYOUT_MONO;
+ ChannelMixingMatrix matrix_builder(
+ input_layout, ChannelLayoutToChannelCount(input_layout), output_layout,
+ ChannelLayoutToChannelCount(output_layout));
+ std::vector<std::vector<float>> matrix;
+ bool remapping = matrix_builder.CreateTransformationMatrix(&matrix);
+
+ // Input: stereo
+ // LEFT RIGHT
+ // Output: mono CENTER 0.5 0.5
+ //
+ EXPECT_FALSE(remapping);
+ EXPECT_EQ(1u, matrix.size());
+ EXPECT_EQ(2u, matrix[0].size());
+ EXPECT_EQ(0.5f, matrix[0][0]);
+ EXPECT_EQ(0.5f, matrix[0][1]);
+}
+
+TEST(ChannelMixingMatrixTest, MonoToStereo) {
+ ChannelLayout input_layout = CHANNEL_LAYOUT_MONO;
+ ChannelLayout output_layout = CHANNEL_LAYOUT_STEREO;
+ ChannelMixingMatrix matrix_builder(
+ input_layout, ChannelLayoutToChannelCount(input_layout), output_layout,
+ ChannelLayoutToChannelCount(output_layout));
+ std::vector<std::vector<float>> matrix;
+ bool remapping = matrix_builder.CreateTransformationMatrix(&matrix);
+
+ // Input: mono
+ // CENTER
+ // Output: stereo LEFT 1
+ // RIGHT 1
+ //
+ EXPECT_TRUE(remapping);
+ EXPECT_EQ(2u, matrix.size());
+ EXPECT_EQ(1u, matrix[0].size());
+ EXPECT_EQ(1.0f, matrix[0][0]);
+ EXPECT_EQ(1u, matrix[1].size());
+ EXPECT_EQ(1.0f, matrix[1][0]);
+}
+
+TEST(ChannelMixingMatrixTest, MonoToTwoOneWithoutVoIPAdjustments) {
+ test::ScopedFieldTrials field_trials(
+ "WebRTC-VoIPChannelRemixingAdjustmentKillSwitch/Enabled/");
+ ChannelLayout input_layout = CHANNEL_LAYOUT_MONO;
+ ChannelLayout output_layout = CHANNEL_LAYOUT_2_1;
+ ChannelMixingMatrix matrix_builder(
+ input_layout, ChannelLayoutToChannelCount(input_layout), output_layout,
+ ChannelLayoutToChannelCount(output_layout));
+ std::vector<std::vector<float>> matrix;
+ bool remapping = matrix_builder.CreateTransformationMatrix(&matrix);
+
+ // Input: mono
+ // CENTER
+ // Output: 2.1 FRONT_LEFT 1
+ // FRONT_RIGHT 1
+ // BACK_CENTER 0
+ //
+ EXPECT_FALSE(remapping);
+ EXPECT_EQ(3u, matrix.size());
+ EXPECT_EQ(1u, matrix[0].size());
+ EXPECT_EQ(1.0f, matrix[0][0]);
+ EXPECT_EQ(1.0f, matrix[1][0]);
+ EXPECT_EQ(0.0f, matrix[2][0]);
+}
+
+TEST(ChannelMixingMatrixTest, MonoToTwoOneWithVoIPAdjustments) {
+ ChannelLayout input_layout = CHANNEL_LAYOUT_MONO;
+ ChannelLayout output_layout = CHANNEL_LAYOUT_2_1;
+ ChannelMixingMatrix matrix_builder(
+ input_layout, ChannelLayoutToChannelCount(input_layout), output_layout,
+ ChannelLayoutToChannelCount(output_layout));
+ std::vector<std::vector<float>> matrix;
+ bool remapping = matrix_builder.CreateTransformationMatrix(&matrix);
+
+ // Input: mono
+ // CENTER
+ // Output: 2.1 FRONT_LEFT 1
+ // FRONT_RIGHT 1
+ // BACK_CENTER 0
+ //
+ EXPECT_TRUE(remapping);
+ EXPECT_EQ(3u, matrix.size());
+ EXPECT_EQ(1u, matrix[0].size());
+ EXPECT_EQ(1.0f, matrix[0][0]);
+ EXPECT_EQ(1.0f, matrix[1][0]);
+ EXPECT_EQ(0.0f, matrix[2][0]);
+}
+
+TEST(ChannelMixingMatrixTest, MonoToFiveOneWithoutVoIPAdjustments) {
+ test::ScopedFieldTrials field_trials(
+ "WebRTC-VoIPChannelRemixingAdjustmentKillSwitch/Enabled/");
+ ChannelLayout input_layout = CHANNEL_LAYOUT_MONO;
+ ChannelLayout output_layout = CHANNEL_LAYOUT_5_1;
+ const int input_channels = ChannelLayoutToChannelCount(input_layout);
+ const int output_channels = ChannelLayoutToChannelCount(output_layout);
+ ChannelMixingMatrix matrix_builder(input_layout, input_channels,
+ output_layout, output_channels);
+ std::vector<std::vector<float>> matrix;
+ bool remapping = matrix_builder.CreateTransformationMatrix(&matrix);
+ // Input: mono
+ // CENTER
+ // Output: 5.1 LEFT 0
+ // RIGHT 0
+ // CENTER 1
+ // LFE 0
+ // SIDE_LEFT 0
+ // SIDE_RIGHT 0
+ //
+ EXPECT_TRUE(remapping);
+ EXPECT_EQ(static_cast<size_t>(output_channels), matrix.size());
+ for (int n = 0; n < output_channels; n++) {
+ EXPECT_EQ(static_cast<size_t>(input_channels), matrix[n].size());
+ if (n == CENTER) {
+ EXPECT_EQ(1.0f, matrix[CENTER][0]);
+ } else {
+ EXPECT_EQ(0.0f, matrix[n][0]);
+ }
+ }
+}
+
+TEST(ChannelMixingMatrixTest, MonoToFiveOneWithVoIPAdjustments) {
+ ChannelLayout input_layout = CHANNEL_LAYOUT_MONO;
+ ChannelLayout output_layout = CHANNEL_LAYOUT_5_1;
+ const int input_channels = ChannelLayoutToChannelCount(input_layout);
+ const int output_channels = ChannelLayoutToChannelCount(output_layout);
+ ChannelMixingMatrix matrix_builder(input_layout, input_channels,
+ output_layout, output_channels);
+ std::vector<std::vector<float>> matrix;
+ bool remapping = matrix_builder.CreateTransformationMatrix(&matrix);
+ // Input: mono
+ // CENTER
+ // Output: 5.1 LEFT 1
+ // RIGHT 1
+ // CENTER 0
+ // LFE 0
+ // SIDE_LEFT 0
+ // SIDE_RIGHT 0
+ //
+ EXPECT_TRUE(remapping);
+ EXPECT_EQ(static_cast<size_t>(output_channels), matrix.size());
+ for (int n = 0; n < output_channels; n++) {
+ EXPECT_EQ(static_cast<size_t>(input_channels), matrix[n].size());
+ if (n == LEFT || n == RIGHT) {
+ EXPECT_EQ(1.0f, matrix[n][0]);
+ } else {
+ EXPECT_EQ(0.0f, matrix[n][0]);
+ }
+ }
+}
+
+TEST(ChannelMixingMatrixTest, MonoToSevenOneWithoutVoIPAdjustments) {
+ test::ScopedFieldTrials field_trials(
+ "WebRTC-VoIPChannelRemixingAdjustmentKillSwitch/Enabled/");
+ ChannelLayout input_layout = CHANNEL_LAYOUT_MONO;
+ ChannelLayout output_layout = CHANNEL_LAYOUT_7_1;
+ const int input_channels = ChannelLayoutToChannelCount(input_layout);
+ const int output_channels = ChannelLayoutToChannelCount(output_layout);
+ ChannelMixingMatrix matrix_builder(input_layout, input_channels,
+ output_layout, output_channels);
+ std::vector<std::vector<float>> matrix;
+ bool remapping = matrix_builder.CreateTransformationMatrix(&matrix);
+ // Input: mono
+ // CENTER
+ // Output: 7.1 LEFT 0
+ // RIGHT 0
+ // CENTER 1
+ // LFE 0
+ // SIDE_LEFT 0
+ // SIDE_RIGHT 0
+ // BACK_LEFT 0
+ // BACK_RIGHT 0
+ //
+ EXPECT_TRUE(remapping);
+ EXPECT_EQ(static_cast<size_t>(output_channels), matrix.size());
+ for (int n = 0; n < output_channels; n++) {
+ EXPECT_EQ(static_cast<size_t>(input_channels), matrix[n].size());
+ if (n == CENTER) {
+ EXPECT_EQ(1.0f, matrix[CENTER][0]);
+ } else {
+ EXPECT_EQ(0.0f, matrix[n][0]);
+ }
+ }
+}
+
+TEST(ChannelMixingMatrixTest, MonoToSevenOneWithVoIPAdjustments) {
+ ChannelLayout input_layout = CHANNEL_LAYOUT_MONO;
+ ChannelLayout output_layout = CHANNEL_LAYOUT_7_1;
+ const int input_channels = ChannelLayoutToChannelCount(input_layout);
+ const int output_channels = ChannelLayoutToChannelCount(output_layout);
+ ChannelMixingMatrix matrix_builder(input_layout, input_channels,
+ output_layout, output_channels);
+ std::vector<std::vector<float>> matrix;
+ bool remapping = matrix_builder.CreateTransformationMatrix(&matrix);
+ // Input: mono
+ // CENTER
+ // Output: 7.1 LEFT 1
+ // RIGHT 1
+ // CENTER 0
+ // LFE 0
+ // SIDE_LEFT 0
+ // SIDE_RIGHT 0
+ // BACK_LEFT 0
+ // BACK_RIGHT 0
+ //
+ EXPECT_TRUE(remapping);
+ EXPECT_EQ(static_cast<size_t>(output_channels), matrix.size());
+ for (int n = 0; n < output_channels; n++) {
+ EXPECT_EQ(static_cast<size_t>(input_channels), matrix[n].size());
+ if (n == LEFT || n == RIGHT) {
+ EXPECT_EQ(1.0f, matrix[n][0]);
+ } else {
+ EXPECT_EQ(0.0f, matrix[n][0]);
+ }
+ }
+}
+
+TEST(ChannelMixingMatrixTest, FiveOneToMono) {
+ ChannelLayout input_layout = CHANNEL_LAYOUT_5_1;
+ ChannelLayout output_layout = CHANNEL_LAYOUT_MONO;
+ ChannelMixingMatrix matrix_builder(
+ input_layout, ChannelLayoutToChannelCount(input_layout), output_layout,
+ ChannelLayoutToChannelCount(output_layout));
+ std::vector<std::vector<float>> matrix;
+ bool remapping = matrix_builder.CreateTransformationMatrix(&matrix);
+
+ // Note: 1/sqrt(2) is shown as 0.707.
+ //
+ // Input: 5.1
+ // LEFT RIGHT CENTER LFE SIDE_LEFT SIDE_RIGHT
+ // Output: mono CENTER 0.707 0.707 1 0.707 0.707 0.707
+ //
+ EXPECT_FALSE(remapping);
+ EXPECT_EQ(1u, matrix.size());
+ EXPECT_EQ(6u, matrix[0].size());
+ EXPECT_FLOAT_EQ(ChannelMixer::kHalfPower, matrix[0][0]);
+ EXPECT_FLOAT_EQ(ChannelMixer::kHalfPower, matrix[0][1]);
+ // The center channel will be mixed at scale 1.
+ EXPECT_EQ(1.0f, matrix[0][2]);
+ EXPECT_FLOAT_EQ(ChannelMixer::kHalfPower, matrix[0][3]);
+ EXPECT_FLOAT_EQ(ChannelMixer::kHalfPower, matrix[0][4]);
+ EXPECT_FLOAT_EQ(ChannelMixer::kHalfPower, matrix[0][5]);
+}
+
+TEST(ChannelMixingMatrixTest, FiveOneBackToStereo) {
+ // Front L, Front R, Front C, LFE, Back L, Back R
+ ChannelLayout input_layout = CHANNEL_LAYOUT_5_1_BACK;
+ ChannelLayout output_layout = CHANNEL_LAYOUT_STEREO;
+ const int input_channels = ChannelLayoutToChannelCount(input_layout);
+ const int output_channels = ChannelLayoutToChannelCount(output_layout);
+ ChannelMixingMatrix matrix_builder(input_layout, input_channels,
+ output_layout, output_channels);
+ std::vector<std::vector<float>> matrix;
+ bool remapping = matrix_builder.CreateTransformationMatrix(&matrix);
+
+ // Note: 1/sqrt(2) is shown as 0.707.
+ // Note: The Channels enumerator is given by {LEFT = 0, RIGHT, CENTER, LFE,
+ // BACK_LEFT, BACK_RIGHT,...}, hence we can use the enumerator values as
+ // indexes in the matrix when verifying the scaling factors.
+ //
+ // Input: 5.1
+ // LEFT RIGHT CENTER LFE BACK_LEFT BACK_RIGHT
+ // Output: stereo LEFT 1 0 0.707 0.707 0.707 0
+ // RIGHT 0 1 0.707 0.707 0 0.707
+ //
+ EXPECT_FALSE(remapping);
+ EXPECT_EQ(static_cast<size_t>(output_channels), matrix.size());
+ EXPECT_EQ(static_cast<size_t>(input_channels), matrix[LEFT].size());
+ EXPECT_EQ(static_cast<size_t>(input_channels), matrix[RIGHT].size());
+ EXPECT_EQ(1.0f, matrix[LEFT][LEFT]);
+ EXPECT_EQ(1.0f, matrix[RIGHT][RIGHT]);
+ EXPECT_EQ(0.0f, matrix[LEFT][RIGHT]);
+ EXPECT_EQ(0.0f, matrix[RIGHT][LEFT]);
+ EXPECT_EQ(0.0f, matrix[LEFT][BACK_RIGHT]);
+ EXPECT_EQ(0.0f, matrix[RIGHT][BACK_LEFT]);
+ EXPECT_FLOAT_EQ(ChannelMixer::kHalfPower, matrix[LEFT][CENTER]);
+ EXPECT_FLOAT_EQ(ChannelMixer::kHalfPower, matrix[LEFT][LFE]);
+ EXPECT_FLOAT_EQ(ChannelMixer::kHalfPower, matrix[LEFT][BACK_LEFT]);
+ EXPECT_FLOAT_EQ(ChannelMixer::kHalfPower, matrix[RIGHT][CENTER]);
+ EXPECT_FLOAT_EQ(ChannelMixer::kHalfPower, matrix[RIGHT][LFE]);
+ EXPECT_FLOAT_EQ(ChannelMixer::kHalfPower, matrix[RIGHT][BACK_RIGHT]);
+}
+
+TEST(ChannelMixingMatrixTest, FiveOneToSevenOne) {
+ // Front L, Front R, Front C, LFE, Side L, Side R
+ ChannelLayout input_layout = CHANNEL_LAYOUT_5_1;
+ // Front L, Front R, Front C, LFE, Side L, Side R, Back L, Back R
+ ChannelLayout output_layout = CHANNEL_LAYOUT_7_1;
+ const int input_channels = ChannelLayoutToChannelCount(input_layout);
+ const int output_channels = ChannelLayoutToChannelCount(output_layout);
+ ChannelMixingMatrix matrix_builder(input_layout, input_channels,
+ output_layout, output_channels);
+ std::vector<std::vector<float>> matrix;
+ bool remapping = matrix_builder.CreateTransformationMatrix(&matrix);
+
+ // Input: 5.1
+ // LEFT RIGHT CENTER LFE SIDE_LEFT SIDE_RIGHT
+ // Output: 7.1 LEFT 1 0 0 0 0 0
+ // RIGHT 0 1 0 0 0 0
+ // CENTER 0 0 1 0 0 0
+ // LFE 0 0 0 1 0 0
+ // SIDE_LEFT 0 0 0 0 1 0
+ // SIDE_RIGHT 0 0 0 0 0 1
+ // BACK_LEFT 0 0 0 0 0 0
+ // BACK_RIGHT 0 0 0 0 0 0
+ //
+ EXPECT_TRUE(remapping);
+ EXPECT_EQ(static_cast<size_t>(output_channels), matrix.size());
+ for (int i = 0; i < output_channels; i++) {
+ EXPECT_EQ(static_cast<size_t>(input_channels), matrix[i].size());
+ for (int j = 0; j < input_channels; j++) {
+ if (i == j) {
+ EXPECT_EQ(1.0f, matrix[i][j]);
+ } else {
+ EXPECT_EQ(0.0f, matrix[i][j]);
+ }
+ }
+ }
+}
+
+TEST(ChannelMixingMatrixTest, StereoToFiveOne) {
+ ChannelLayout input_layout = CHANNEL_LAYOUT_STEREO;
+ ChannelLayout output_layout = CHANNEL_LAYOUT_5_1;
+ const int input_channels = ChannelLayoutToChannelCount(input_layout);
+ const int output_channels = ChannelLayoutToChannelCount(output_layout);
+ ChannelMixingMatrix matrix_builder(input_layout, input_channels,
+ output_layout, output_channels);
+ std::vector<std::vector<float>> matrix;
+ bool remapping = matrix_builder.CreateTransformationMatrix(&matrix);
+
+ // Input: Stereo
+ // LEFT RIGHT
+ // Output: 5.1 LEFT 1 0
+ // RIGHT 0 1
+ // CENTER 0 0
+ // LFE 0 0
+ // SIDE_LEFT 0 0
+ // SIDE_RIGHT 0 0
+ //
+ EXPECT_TRUE(remapping);
+ EXPECT_EQ(static_cast<size_t>(output_channels), matrix.size());
+ for (int n = 0; n < output_channels; n++) {
+ EXPECT_EQ(static_cast<size_t>(input_channels), matrix[n].size());
+ if (n == LEFT) {
+ EXPECT_EQ(1.0f, matrix[LEFT][LEFT]);
+ EXPECT_EQ(0.0f, matrix[LEFT][RIGHT]);
+ } else if (n == RIGHT) {
+ EXPECT_EQ(0.0f, matrix[RIGHT][LEFT]);
+ EXPECT_EQ(1.0f, matrix[RIGHT][RIGHT]);
+ } else {
+ EXPECT_EQ(0.0f, matrix[n][LEFT]);
+ EXPECT_EQ(0.0f, matrix[n][RIGHT]);
+ }
+ }
+}
+
+TEST(ChannelMixingMatrixTest, DiscreteToDiscrete) {
+ const struct {
+ int input_channels;
+ int output_channels;
+ } test_case[] = {
+ {2, 2},
+ {2, 5},
+ {5, 2},
+ };
+
+ for (size_t n = 0; n < arraysize(test_case); n++) {
+ int input_channels = test_case[n].input_channels;
+ int output_channels = test_case[n].output_channels;
+ ChannelMixingMatrix matrix_builder(CHANNEL_LAYOUT_DISCRETE, input_channels,
+ CHANNEL_LAYOUT_DISCRETE,
+ output_channels);
+ std::vector<std::vector<float>> matrix;
+ bool remapping = matrix_builder.CreateTransformationMatrix(&matrix);
+ EXPECT_TRUE(remapping);
+ EXPECT_EQ(static_cast<size_t>(output_channels), matrix.size());
+ for (int i = 0; i < output_channels; i++) {
+ EXPECT_EQ(static_cast<size_t>(input_channels), matrix[i].size());
+ for (int j = 0; j < input_channels; j++) {
+ if (i == j) {
+ EXPECT_EQ(1.0f, matrix[i][j]);
+ } else {
+ EXPECT_EQ(0.0f, matrix[i][j]);
+ }
+ }
+ }
+ }
+}
+
+} // namespace webrtc