Implement renderer AudioDevice API for low-latency audio output...

media/audio/audio_util.cc

 // Copyright (c) 2010 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.
 
 // Software adjust volume of samples, allows each audio stream its own
 // volume without impacting master volume for chrome and other applications.
 
 // Implemented as templates to allow 8, 16 and 32 bit implementations.
 // 8 bit is unsigned and biased by 128.
 
@@ skipping 186 matching lines @@
       }
       return true;
     }
 
     default:
      break;
   }
   return false;
 }
 
+void InterleaveFloatToInt16(const std::vector<float*>& source,
+                            int16* destination,
+                            size_t number_of_frames) {
+  const float kScale = 32768.0f;
+  int channels = source.size();
+  for (int i = 0; i < channels; ++i) {
+    float* channel_data = source[i];
+    for (size_t j = 0; j < number_of_frames; ++j) {
+      float sample = kScale * channel_data[j];
+      if (sample < -32768.0)
+        sample = -32768.0;
+      else if (sample > 32767.0)
+        sample = 32767.0;
+
+      destination[j * channels + i] = static_cast<int16>(sample);
+    }
+  }
+}
+
 }  // namespace media