1 files changed, 102 insertions, 0 deletions
diff --git a/third_party/libwebrtc/modules/audio_processing/ns/noise_suppressor_unittest.cc b/third_party/libwebrtc/modules/audio_processing/ns/noise_suppressor_unittest.cc
new file mode 100644
index 0000000000..28ea63ae40
--- /dev/null
+++ b/third_party/libwebrtc/modules/audio_processing/ns/noise_suppressor_unittest.cc
@@ -0,0 +1,102 @@
+/*
+ *  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.
+ */
+
+#include "modules/audio_processing/ns/noise_suppressor.h"
+
+#include <deque>
+#include <memory>
+#include <string>
+#include <utility>
+#include <vector>
+
+#include "rtc_base/strings/string_builder.h"
+#include "test/gmock.h"
+#include "test/gtest.h"
+
+namespace webrtc {
+namespace {
+
+std::string ProduceDebugText(int sample_rate_hz,
+                             size_t num_channels,
+                             NsConfig::SuppressionLevel level) {
+  rtc::StringBuilder ss;
+  ss << "Sample rate: " << sample_rate_hz << ", num_channels: " << num_channels
+     << ", level: " << static_cast<int>(level);
+  return ss.Release();
+}
+
+void PopulateInputFrameWithIdenticalChannels(size_t num_channels,
+                                             size_t num_bands,
+                                             size_t frame_index,
+                                             AudioBuffer* audio) {
+  for (size_t ch = 0; ch < num_channels; ++ch) {
+    for (size_t b = 0; b < num_bands; ++b) {
+      for (size_t i = 0; i < 160; ++i) {
+        float value = static_cast<int>(frame_index * 160 + i);
+        audio->split_bands(ch)[b][i] = (value > 0 ? 5000 * b + value : 0);
+      }
+    }
+  }
+}
+
+void VerifyIdenticalChannels(size_t num_channels,
+                             size_t num_bands,
+                             size_t frame_index,
+                             const AudioBuffer& audio) {
+  EXPECT_GT(num_channels, 1u);
+  for (size_t ch = 1; ch < num_channels; ++ch) {
+    for (size_t b = 0; b < num_bands; ++b) {
+      for (size_t i = 0; i < 160; ++i) {
+        EXPECT_EQ(audio.split_bands_const(ch)[b][i],
+                  audio.split_bands_const(0)[b][i]);
+      }
+    }
+  }
+}
+
+}  // namespace
+
+// Verifies that the same noise reduction effect is applied to all channels.
+TEST(NoiseSuppressor, IdenticalChannelEffects) {
+  for (auto rate : {16000, 32000, 48000}) {
+    for (auto num_channels : {1, 4, 8}) {
+      for (auto level :
+           {NsConfig::SuppressionLevel::k6dB, NsConfig::SuppressionLevel::k12dB,
+            NsConfig::SuppressionLevel::k18dB,
+            NsConfig::SuppressionLevel::k21dB}) {
+        SCOPED_TRACE(ProduceDebugText(rate, num_channels, level));
+
+        const size_t num_bands = rate / 16000;
+        // const int frame_length = rtc::CheckedDivExact(rate, 100);
+        AudioBuffer audio(rate, num_channels, rate, num_channels, rate,
+                          num_channels);
+        NsConfig cfg;
+        NoiseSuppressor ns(cfg, rate, num_channels);
+        for (size_t frame_index = 0; frame_index < 1000; ++frame_index) {
+          if (rate > 16000) {
+            audio.SplitIntoFrequencyBands();
+          }
+
+          PopulateInputFrameWithIdenticalChannels(num_channels, num_bands,
+                                                  frame_index, &audio);
+
+          ns.Analyze(audio);
+          ns.Process(&audio);
+          if (num_channels > 1) {
+            VerifyIdenticalChannels(num_channels, num_bands, frame_index,
+                                    audio);
+          }
+        }
+      }
+    }
+  }
+}
+
+}  // namespace webrtc