Moving src/webrtc into src/.

In order to eliminate the WebRTC Subtree mirror in Chromium, 
WebRTC is moving the content of the src/webrtc directory up
to the src/ directory.

NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
TBR=tommi@webrtc.org

Bug: chromium:611808
Change-Id: Iac59c5b51b950f174119565bac87955a7994bc38
Reviewed-on: https://webrtc-review.googlesource.com/1560
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Reviewed-by: Henrik Kjellander <kjellander@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#19845}

modules/audio_coding/neteq/decision_logic.h

@@ -0,0 +1,168 @@
+/*
+ *  Copyright (c) 2013 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.
+ */
+
+#ifndef WEBRTC_MODULES_AUDIO_CODING_NETEQ_DECISION_LOGIC_H_
+#define WEBRTC_MODULES_AUDIO_CODING_NETEQ_DECISION_LOGIC_H_
+
+#include "webrtc/modules/audio_coding/neteq/defines.h"
+#include "webrtc/modules/audio_coding/neteq/include/neteq.h"
+#include "webrtc/modules/audio_coding/neteq/tick_timer.h"
+#include "webrtc/rtc_base/constructormagic.h"
+#include "webrtc/typedefs.h"
+
+namespace webrtc {
+
+// Forward declarations.
+class BufferLevelFilter;
+class DecoderDatabase;
+class DelayManager;
+class Expand;
+class PacketBuffer;
+class SyncBuffer;
+struct Packet;
+
+// This is the base class for the decision tree implementations. Derived classes
+// must implement the method GetDecisionSpecialized().
+class DecisionLogic {
+ public:
+  // Static factory function which creates different types of objects depending
+  // on the |playout_mode|.
+  static DecisionLogic* Create(int fs_hz,
+                               size_t output_size_samples,
+                               NetEqPlayoutMode playout_mode,
+                               DecoderDatabase* decoder_database,
+                               const PacketBuffer& packet_buffer,
+                               DelayManager* delay_manager,
+                               BufferLevelFilter* buffer_level_filter,
+                               const TickTimer* tick_timer);
+
+  // Constructor.
+  DecisionLogic(int fs_hz,
+                size_t output_size_samples,
+                NetEqPlayoutMode playout_mode,
+                DecoderDatabase* decoder_database,
+                const PacketBuffer& packet_buffer,
+                DelayManager* delay_manager,
+                BufferLevelFilter* buffer_level_filter,
+                const TickTimer* tick_timer);
+
+  virtual ~DecisionLogic();
+
+  // Resets object to a clean state.
+  void Reset();
+
+  // Resets parts of the state. Typically done when switching codecs.
+  void SoftReset();
+
+  // Sets the sample rate and the output block size.
+  void SetSampleRate(int fs_hz, size_t output_size_samples);
+
+  // Returns the operation that should be done next. |sync_buffer| and |expand|
+  // are provided for reference. |decoder_frame_length| is the number of samples
+  // obtained from the last decoded frame. If there is a packet available, it
+  // should be supplied in |next_packet|; otherwise it should be NULL. The mode
+  // resulting from the last call to NetEqImpl::GetAudio is supplied in
+  // |prev_mode|. If there is a DTMF event to play, |play_dtmf| should be set to
+  // true. The output variable |reset_decoder| will be set to true if a reset is
+  // required; otherwise it is left unchanged (i.e., it can remain true if it
+  // was true before the call).  This method end with calling
+  // GetDecisionSpecialized to get the actual return value.
+  Operations GetDecision(const SyncBuffer& sync_buffer,
+                         const Expand& expand,
+                         size_t decoder_frame_length,
+                         const Packet* next_packet,
+                         Modes prev_mode,
+                         bool play_dtmf,
+                         size_t generated_noise_samples,
+                         bool* reset_decoder);
+
+  // These methods test the |cng_state_| for different conditions.
+  bool CngRfc3389On() const { return cng_state_ == kCngRfc3389On; }
+  bool CngOff() const { return cng_state_ == kCngOff; }
+
+  // Resets the |cng_state_| to kCngOff.
+  void SetCngOff() { cng_state_ = kCngOff; }
+
+  // Reports back to DecisionLogic whether the decision to do expand remains or
+  // not. Note that this is necessary, since an expand decision can be changed
+  // to kNormal in NetEqImpl::GetDecision if there is still enough data in the
+  // sync buffer.
+  virtual void ExpandDecision(Operations operation);
+
+  // Adds |value| to |sample_memory_|.
+  void AddSampleMemory(int32_t value) {
+    sample_memory_ += value;
+  }
+
+  // Accessors and mutators.
+  void set_sample_memory(int32_t value) { sample_memory_ = value; }
+  size_t noise_fast_forward() const { return noise_fast_forward_; }
+  size_t packet_length_samples() const { return packet_length_samples_; }
+  void set_packet_length_samples(size_t value) {
+    packet_length_samples_ = value;
+  }
+  void set_prev_time_scale(bool value) { prev_time_scale_ = value; }
+  NetEqPlayoutMode playout_mode() const { return playout_mode_; }
+
+ protected:
+  // The value 5 sets maximum time-stretch rate to about 100 ms/s.
+  static const int kMinTimescaleInterval = 5;
+
+  enum CngState {
+    kCngOff,
+    kCngRfc3389On,
+    kCngInternalOn
+  };
+
+  // Returns the operation that should be done next. |sync_buffer| and |expand|
+  // are provided for reference. |decoder_frame_length| is the number of samples
+  // obtained from the last decoded frame. If there is a packet available, it
+  // should be supplied in |next_packet|; otherwise it should be NULL. The mode
+  // resulting from the last call to NetEqImpl::GetAudio is supplied in
+  // |prev_mode|. If there is a DTMF event to play, |play_dtmf| should be set to
+  // true. The output variable |reset_decoder| will be set to true if a reset is
+  // required; otherwise it is left unchanged (i.e., it can remain true if it
+  // was true before the call).  Should be implemented by derived classes.
+  virtual Operations GetDecisionSpecialized(const SyncBuffer& sync_buffer,
+                                            const Expand& expand,
+                                            size_t decoder_frame_length,
+                                            const Packet* next_packet,
+                                            Modes prev_mode,
+                                            bool play_dtmf,
+                                            bool* reset_decoder,
+                                            size_t generated_noise_samples) = 0;
+
+  // Updates the |buffer_level_filter_| with the current buffer level
+  // |buffer_size_packets|.
+  void FilterBufferLevel(size_t buffer_size_packets, Modes prev_mode);
+
+  DecoderDatabase* decoder_database_;
+  const PacketBuffer& packet_buffer_;
+  DelayManager* delay_manager_;
+  BufferLevelFilter* buffer_level_filter_;
+  const TickTimer* tick_timer_;
+  int fs_mult_;
+  size_t output_size_samples_;
+  CngState cng_state_;  // Remember if comfort noise is interrupted by other
+                        // event (e.g., DTMF).
+  size_t noise_fast_forward_ = 0;
+  size_t packet_length_samples_;
+  int sample_memory_;
+  bool prev_time_scale_;
+  std::unique_ptr<TickTimer::Countdown> timescale_countdown_;
+  int num_consecutive_expands_;
+  const NetEqPlayoutMode playout_mode_;
+
+ private:
+  RTC_DISALLOW_COPY_AND_ASSIGN(DecisionLogic);
+};
+
+}  // namespace webrtc
+#endif  // WEBRTC_MODULES_AUDIO_CODING_NETEQ_DECISION_LOGIC_H_