Update common_audio

Corresponds to upstream commit 524e9b043e7e86fd72353b987c9d5f6a1ebf83e1

Update notes:

 * Moved src/ to webrtc/ to easily diff against the third_party/webrtc
   in the chromium tree

 * ARM/NEON/MIPS support is not yet hooked up

 * Tests have not been copied

webrtc/modules/audio_processing/utility/delay_estimator.h

@@ -0,0 +1,154 @@
+/*
+ *  Copyright (c) 2011 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.
+ */
+
+// Performs delay estimation on a block by block basis
+// The return value is  0 - OK and -1 - Error, unless otherwise stated.
+
+#ifndef WEBRTC_MODULES_AUDIO_PROCESSING_UTILITY_DELAY_ESTIMATOR_H_
+#define WEBRTC_MODULES_AUDIO_PROCESSING_UTILITY_DELAY_ESTIMATOR_H_
+
+#include "typedefs.h"
+
+// Releases the memory allocated by WebRtc_CreateDelayEstimator(...)
+// Input:
+//      - handle        : Pointer to the delay estimation instance
+//
+int WebRtc_FreeDelayEstimator(void* handle);
+
+// Allocates the memory needed by the delay estimation. The memory needs to be
+// initialized separately using the WebRtc_InitDelayEstimator(...)
+// function.
+//
+// Inputs:
+//      - handle            : Instance that should be created
+//      - spectrum_size     : Size of the spectrum used both in far end and
+//                            near end. Used to allocate memory for spectrum
+//                            specific buffers.
+//      - history_size      : Size of the far end history used to estimate the
+//                            delay from. Used to allocate memory for history
+//                            specific buffers.
+//      - enable_alignment  : With this mode set to 1, a far end history is
+//                            created, so that the user can retrieve aligned
+//                            far end spectra using
+//                            WebRtc_AlignedFarend(...). Otherwise, only delay
+//                            values are calculated.
+//
+// Output:
+//      - handle            : Created instance
+//
+int WebRtc_CreateDelayEstimator(void** handle,
+                                int spectrum_size,
+                                int history_size,
+                                int enable_alignment);
+
+// Initializes the delay estimation instance created with
+// WebRtc_CreateDelayEstimator(...)
+// Input:
+//      - handle        : Pointer to the delay estimation instance
+//
+// Output:
+//      - handle        : Initialized instance
+//
+int WebRtc_InitDelayEstimator(void* handle);
+
+// Estimates and returns the delay between the far end and near end blocks.
+// Inputs:
+//      - handle        : Pointer to the delay estimation instance
+//      - far_spectrum  : Pointer to the far end spectrum data
+//      - near_spectrum : Pointer to the near end spectrum data of the current
+//                        block
+//      - spectrum_size : The size of the data arrays (same for both far and
+//                        near end)
+//      - far_q         : The Q-domain of the far end data
+//      - vad_value     : The VAD decision of the current block
+//
+// Output:
+//      - handle        : Updated instance
+//
+// Return value:
+//      - delay         :  >= 0 - Calculated delay value
+//                        -1    - Error
+//
+int WebRtc_DelayEstimatorProcess(void* handle,
+                                 uint16_t* far_spectrum,
+                                 uint16_t* near_spectrum,
+                                 int spectrum_size,
+                                 int far_q,
+                                 int vad_value);
+
+// Returns a pointer to the far end spectrum aligned to current near end
+// spectrum. The function WebRtc_DelayEstimatorProcess(...) should have been
+// called before WebRtc_AlignedFarend(...). Otherwise, you get the pointer to
+// the previous frame. The memory is only valid until the next call of
+// WebRtc_DelayEstimatorProcess(...).
+//
+// Inputs:
+//      - handle            : Pointer to the delay estimation instance
+//      - far_spectrum_size : Size of far_spectrum allocated by the caller
+//
+// Output:
+//      - far_q             : The Q-domain of the aligned far end spectrum
+//
+// Return value:
+//      - far_spectrum      : Pointer to the aligned far end spectrum
+//                            NULL - Error
+//
+const uint16_t* WebRtc_AlignedFarend(void* handle,
+                                     int far_spectrum_size,
+                                     int* far_q);
+
+// Returns the last calculated delay updated by the function
+// WebRtc_DelayEstimatorProcess(...)
+//
+// Input:
+//      - handle        : Pointer to the delay estimation instance
+//
+// Return value:
+//      - delay         :  >= 0 - Last calculated delay value
+//                        -1    - Error
+//
+int WebRtc_last_delay(void* handle);
+
+// Returns the history size used in the far end buffers to calculate the delay
+// over.
+//
+// Input:
+//      - handle        : Pointer to the delay estimation instance
+//
+// Return value:
+//      - history_size  :  > 0  - Far end history size
+//                        -1    - Error
+//
+int WebRtc_history_size(void* handle);
+
+// Returns the fixed spectrum size used in the algorithm.
+//
+// Input:
+//      - handle        : Pointer to the delay estimation instance
+//
+// Return value:
+//      - spectrum_size :  > 0  - Spectrum size
+//                        -1    - Error
+//
+int WebRtc_spectrum_size(void* handle);
+
+// Returns 1 if the far end alignment is enabled and 0 otherwise.
+//
+// Input:
+//      - handle        : Pointer to the delay estimation instance
+//
+// Return value:
+//      - alignment_enabled : 1 - Enabled
+//                            0 - Disabled
+//                           -1 - Error
+//
+int WebRtc_is_alignment_enabled(void* handle);
+
+#endif  // WEBRTC_MODULES_AUDIO_PROCESSING_UTILITY_DELAY_ESTIMATOR_H_