Add a virtual beamforming audio device on ChromeOS.

content/public/common/media_stream_request.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_PUBLIC_COMMON_MEDIA_STREAM_REQUEST_H_
 #define CONTENT_PUBLIC_COMMON_MEDIA_STREAM_REQUEST_H_
 
 #include <map>
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/callback_forward.h"
 #include "base/memory/scoped_ptr.h"
 #include "content/common/content_export.h"
+#include "media/audio/audio_parameters.h"
 #include "ui/gfx/native_widget_types.h"
 #include "url/gurl.h"
 
 namespace content {
 
 // Types of media streams.
 enum MediaStreamType {
   MEDIA_NO_SERVICE = 0,
 
   // A device provided by the operating system (e.g., webcam input).
@@ skipping 92 matching lines @@
 
   // The device id of a matched output device if any (otherwise empty).
   // Only applicable to audio devices.
   std::string matched_output_device_id;
 
   // The device's "friendly" name. Not guaranteed to be unique.
   std::string name;
 
   // Contains properties that match directly with those with the same name
   // in media::AudioParameters.
   struct AudioDeviceParameters {

[ajm, 2015/09/02 06:47:01]

This should probably _be_ a media::AudioParameters. I added a checkdeps
exception for this to make that clear.

I'll add a TODO on myself here if you agree, but would prefer not to make the
change in this CL.

[tommi (sloooow) - chröme, 2015/09/02 07:43:07]

I agree.  It's basically a poor man's copy of it.  The reason this is here
though is that we got push back for adding AudioParameters here way back when. 
We started out with only needing a couple of parameters, but things have grown
quite a bit since then.

If you'd like to fix this (not in this cl), then that would be great.

[ajm, 2015/09/02 17:00:55]

I'll add the TODO.

-    AudioDeviceParameters()
-        : sample_rate(), channel_layout(), frames_per_buffer(), effects() {
-    }
+    AudioDeviceParameters();
+    AudioDeviceParameters(int sample_rate,
+                          int channel_layout,
+                          int frames_per_buffer);
 
-    AudioDeviceParameters(int sample_rate, int channel_layout,
-        int frames_per_buffer)
-        : sample_rate(sample_rate),
-          channel_layout(channel_layout),
-          frames_per_buffer(frames_per_buffer),
-          effects() {
-    }
+    ~AudioDeviceParameters();
 
     // Preferred sample rate in samples per second for the device.
     int sample_rate;
 
     // Preferred channel configuration for the device.
     // TODO(henrika): ideally, we would like to use media::ChannelLayout here
     // but including media/base/channel_layout.h violates checkdeps rules.
     int channel_layout;
 
     // Preferred number of frames per buffer for the device.  This is filled
     // in on the browser side and can be used by the renderer to match the
     // expected browser side settings and avoid unnecessary buffering.
     // See media::AudioParameters for more.
     int frames_per_buffer;
 
     // See media::AudioParameters::PlatformEffectsMask.
     int effects;
+
+    std::vector<media::Point> mic_positions;
   };
 
   // These below two member variables are valid only when the type of device is
   // audio (i.e. IsAudioInputMediaType returns true).
 
   // Contains the device properties of the capture device.
   AudioDeviceParameters input;
 
   // If the capture device has an associated output device (e.g. headphones),
   // this will contain the properties for the output device.  If no such device
@@ skipping 92 matching lines @@
 
 // Callback used return results of media access requests.
 typedef base::Callback<void(
     const MediaStreamDevices& devices,
     content::MediaStreamRequestResult result,
     scoped_ptr<MediaStreamUI> ui)> MediaResponseCallback;
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_COMMON_MEDIA_STREAM_REQUEST_H_