Integrate Intelligibility with APM

webrtc/common_audio/include/audio_util.h

Index: webrtc/common_audio/include/audio_util.h
diff --git a/webrtc/common_audio/include/audio_util.h b/webrtc/common_audio/include/audio_util.h
index 8262649145546180f23b6e82094d324b7f604e7f..b0ecc068198afbbca001409e6003352e9bf83015 100644
--- a/webrtc/common_audio/include/audio_util.h
+++ b/webrtc/common_audio/include/audio_util.h
@@ -97,6 +97,21 @@ void Interleave(const T* const* deinterleaved, int samples_per_channel,
   }
 }
 
+// Copies audio from a single channel buffer pointed to by |mono| to each
+// channel of |interleaved|. There must be sufficient space allocated in
+// |interleaved| (|samples_per_channel| * |num_channels|).
+template <typename T>
+void UpmixMonoToInterleaved(const T* mono, int samples_per_channel,

[Andrew MacDonald, 2015/07/29 03:52:27]

Go with num_frames for new code rather than samples_per_channel.

[ekm, 2015/07/29 23:35:06]

Done.

+                            int num_channels, T* interleaved) {
+  int interleaved_idx = 0;
+  for (int i = 0; i < samples_per_channel; ++i) {
+    for (int j = 0; j < num_channels; ++j) {
+      interleaved[interleaved_idx] = mono[i];

[aluebs-webrtc, 2015/07/29 22:17:10]

How about:

interleaved[i * num_channels + j] = mono[i];

And drop interleaved_idx completely?

[ekm, 2015/07/29 23:35:06]

I'd like to avoid the inner multiplication, though not of the tradeoff in
practice vs declaring the int every call.

[aluebs-webrtc, 2015/07/30 15:28:07]

Agreed.

+      interleaved_idx++;

[Andrew MacDonald, 2015/07/29 03:52:27]

nit: could put the post-increment in the above line.

[ekm, 2015/07/29 23:35:06]

Done.

+    }
+  }
+}
+
 }  // namespace webrtc
 
 #endif  // WEBRTC_COMMON_AUDIO_INCLUDE_AUDIO_UTIL_H_