Allow more than 2 input channels in AudioProcessing.

webrtc/common_audio/audio_util_unittest.cc

Index: webrtc/common_audio/audio_util_unittest.cc
diff --git a/webrtc/common_audio/audio_util_unittest.cc b/webrtc/common_audio/audio_util_unittest.cc
index 2cdf53813c1bf603c859bd80e6108a6bfee803e5..e449f8ac46f48e6801685006ec9e2501885987b6 100644
--- a/webrtc/common_audio/audio_util_unittest.cc
+++ b/webrtc/common_audio/audio_util_unittest.cc
@@ -8,11 +8,15 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
+#include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "webrtc/common_audio/include/audio_util.h"
 #include "webrtc/typedefs.h"
 
 namespace webrtc {
+namespace {
+
+using ::testing::ElementsAreArray;
 
 void ExpectArraysEq(const int16_t* ref, const int16_t* test, int length) {
   for (int i = 0; i < length; ++i) {
@@ -114,4 +118,128 @@ TEST(AudioUtilTest, InterleavingMonoIsIdentical) {
   ExpectArraysEq(mono, interleaved, kSamplesPerChannel);
 }
 
+TEST(AudioUtilTest, DownmixInterleavedToMonoImpl) {
+  {
+    const int kNumMultichannelFrames = 4;
+    const int kNumChannels = 1;
+    const float interleaved[kNumChannels * kNumMultichannelFrames] = {
+        1.f, 2.f, -1.f, -3.f};
+    float deinterleaved[kNumMultichannelFrames];
+
+    DownmixInterleavedToMonoImpl<float, float>(
+        interleaved, kNumMultichannelFrames, kNumChannels, deinterleaved);
+
+    EXPECT_THAT(deinterleaved, ElementsAreArray(interleaved));
+  }
+  {
+    const int kNumMultichannelFrames = 2;
+    const int kNumChannels = 2;
+    const float interleaved[kNumChannels * kNumMultichannelFrames] = {
+        1.f, 2.f, -1.f, -3.f};
+    float deinterleaved[kNumMultichannelFrames];
+
+    DownmixInterleavedToMonoImpl<float, float>(
+        interleaved, kNumMultichannelFrames, kNumChannels, deinterleaved);
+    const float expected[kNumMultichannelFrames] = {1.5f, -2.f};
+
+    EXPECT_THAT(deinterleaved, ElementsAreArray(expected));
+  }
+  {
+    const int kNumMultichannelFrames = 2;
+    const int kNumChannels = 3;
+    const float interleaved[kNumChannels * kNumMultichannelFrames] = {
+        1.f, 2.f, 3.f, -1.f, -3.f, 7.f};
+    float deinterleaved[kNumMultichannelFrames];
+
+    DownmixInterleavedToMonoImpl<float, float>(
+        interleaved, kNumMultichannelFrames, kNumChannels, deinterleaved);
+    const float expected[kNumMultichannelFrames] = {2.f, 1.f};
+
+    EXPECT_THAT(deinterleaved, ElementsAreArray(expected));
+  }
+  {
+    const int kNumMultichannelFrames = 2;
+    const int kNumChannels = 2;
+    const int16_t interleaved[kNumChannels * kNumMultichannelFrames] = {
+        10, 20, -10, -30};
+    int16_t deinterleaved[kNumMultichannelFrames];
+
+    DownmixInterleavedToMonoImpl<int16_t, int32_t>(
+        interleaved, kNumMultichannelFrames, kNumChannels, deinterleaved);
+    const int16_t expected[kNumMultichannelFrames] = {15, -20};
+
+    EXPECT_THAT(deinterleaved, ElementsAreArray(expected));
+  }
+  {
+    const int kNumMultichannelFrames = 3;
+    const int kNumChannels = 3;
+    const int16_t interleaved[kNumChannels * kNumMultichannelFrames] = {
+        30000, 30000, 24001, -5, -10, -20, -30000, -30999, -30000};
+    int16_t deinterleaved[kNumMultichannelFrames];
+
+    DownmixInterleavedToMonoImpl<int16_t, int32_t>(
+        interleaved, kNumMultichannelFrames, kNumChannels, deinterleaved);
+    const int16_t expected[kNumMultichannelFrames] = {28000, -11, -30333};
+
+    EXPECT_THAT(deinterleaved, ElementsAreArray(expected));
+  }
+}
+
+TEST(AudioUtilTest, DownmixToMonoTest) {
+  {
+    const int kNumMultichannelFrames = 4;
+    const int kNumChannels = 1;
+    const float input_data[kNumChannels][kNumMultichannelFrames] = {
+        {1.f, 2.f, -1.f, -3.f}};
+    const float* input[kNumChannels];
+    for (int i = 0; i < kNumChannels; ++i) {
+      input[i] = input_data[i];
+    }
+
+    float downmixed[kNumMultichannelFrames];
+
+    DownmixToMono<float, float>(input, kNumMultichannelFrames, kNumChannels,
+                                downmixed);
+
+    EXPECT_THAT(downmixed, ElementsAreArray(input_data[0]));
+  }
+  {
+    const int kNumMultichannelFrames = 3;
+    const int kNumChannels = 2;
+    const float input_data[kNumChannels][kNumMultichannelFrames] = {
+        {1.f, 2.f, -1.f}, {3.f, 0.f, 1.f}};
+    const float* input[kNumChannels];
+    for (int i = 0; i < kNumChannels; ++i) {
+      input[i] = input_data[i];
+    }
+
+    float downmixed[kNumMultichannelFrames];
+    const float expected[kNumMultichannelFrames] = {2.f, 1.f, 0.f};
+
+    DownmixToMono<float, float>(input, kNumMultichannelFrames, kNumChannels,
+                                downmixed);
+
+    EXPECT_THAT(downmixed, ElementsAreArray(expected));
+  }
+  {
+    const int kNumMultichannelFrames = 3;
+    const int kNumChannels = 3;
+    const int16_t input_data[kNumChannels][kNumMultichannelFrames] = {
+        {30000, -5, -30000}, {30000, -10, -30999}, {24001, -20, -30000}};
+    const int16_t* input[kNumChannels];
+    for (int i = 0; i < kNumChannels; ++i) {
+      input[i] = input_data[i];
+    }
+
+    int16_t downmixed[kNumMultichannelFrames];
+    const int16_t expected[kNumMultichannelFrames] = {28000, -11, -30333};
+
+    DownmixToMono<int16_t, int32_t>(input, kNumMultichannelFrames, kNumChannels,
+                                downmixed);
+
+    EXPECT_THAT(downmixed, ElementsAreArray(expected));
+  }
+}
+
+}  // namespace
 }  // namespace webrtc