Update to current webrtc library

This is from the upstream library commit id
3326535126e435f1ba647885ce43a8f0f3d317eb, corresponding to Chromium
88.0.4290.1.

webrtc/api/audio/audio_frame.h

@@ -0,0 +1,177 @@
+/*
+ *  Copyright (c) 2018 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 API_AUDIO_AUDIO_FRAME_H_
+#define API_AUDIO_AUDIO_FRAME_H_
+
+#include <stddef.h>
+#include <stdint.h>
+
+#include <utility>
+
+#include "api/audio/channel_layout.h"
+#include "api/rtp_packet_infos.h"
+#include "rtc_base/constructor_magic.h"
+
+namespace webrtc {
+
+/* This class holds up to 120 ms of super-wideband (32 kHz) stereo audio. It
+ * allows for adding and subtracting frames while keeping track of the resulting
+ * states.
+ *
+ * Notes
+ * - This is a de-facto api, not designed for external use. The AudioFrame class
+ *   is in need of overhaul or even replacement, and anyone depending on it
+ *   should be prepared for that.
+ * - The total number of samples is samples_per_channel_ * num_channels_.
+ * - Stereo data is interleaved starting with the left channel.
+ */
+class AudioFrame {
+ public:
+  // Using constexpr here causes linker errors unless the variable also has an
+  // out-of-class definition, which is impractical in this header-only class.
+  // (This makes no sense because it compiles as an enum value, which we most
+  // certainly cannot take the address of, just fine.) C++17 introduces inline
+  // variables which should allow us to switch to constexpr and keep this a
+  // header-only class.
+  enum : size_t {
+    // Stereo, 32 kHz, 120 ms (2 * 32 * 120)
+    // Stereo, 192 kHz, 20 ms (2 * 192 * 20)
+    kMaxDataSizeSamples = 7680,
+    kMaxDataSizeBytes = kMaxDataSizeSamples * sizeof(int16_t),
+  };
+
+  enum VADActivity { kVadActive = 0, kVadPassive = 1, kVadUnknown = 2 };
+  enum SpeechType {
+    kNormalSpeech = 0,
+    kPLC = 1,
+    kCNG = 2,
+    kPLCCNG = 3,
+    kCodecPLC = 5,
+    kUndefined = 4
+  };
+
+  AudioFrame();
+
+  friend void swap(AudioFrame& a, AudioFrame& b);
+
+  // Resets all members to their default state.
+  void Reset();
+  // Same as Reset(), but leaves mute state unchanged. Muting a frame requires
+  // the buffer to be zeroed on the next call to mutable_data(). Callers
+  // intending to write to the buffer immediately after Reset() can instead use
+  // ResetWithoutMuting() to skip this wasteful zeroing.
+  void ResetWithoutMuting();
+
+  void UpdateFrame(uint32_t timestamp,
+                   const int16_t* data,
+                   size_t samples_per_channel,
+                   int sample_rate_hz,
+                   SpeechType speech_type,
+                   VADActivity vad_activity,
+                   size_t num_channels = 1);
+
+  void CopyFrom(const AudioFrame& src);
+
+  // Sets a wall-time clock timestamp in milliseconds to be used for profiling
+  // of time between two points in the audio chain.
+  // Example:
+  //   t0: UpdateProfileTimeStamp()
+  //   t1: ElapsedProfileTimeMs() => t1 - t0 [msec]
+  void UpdateProfileTimeStamp();
+  // Returns the time difference between now and when UpdateProfileTimeStamp()
+  // was last called. Returns -1 if UpdateProfileTimeStamp() has not yet been
+  // called.
+  int64_t ElapsedProfileTimeMs() const;
+
+  // data() returns a zeroed static buffer if the frame is muted.
+  // mutable_frame() always returns a non-static buffer; the first call to
+  // mutable_frame() zeros the non-static buffer and marks the frame unmuted.
+  const int16_t* data() const;
+  int16_t* mutable_data();
+
+  // Prefer to mute frames using AudioFrameOperations::Mute.
+  void Mute();
+  // Frame is muted by default.
+  bool muted() const;
+
+  size_t max_16bit_samples() const { return kMaxDataSizeSamples; }
+  size_t samples_per_channel() const { return samples_per_channel_; }
+  size_t num_channels() const { return num_channels_; }
+  ChannelLayout channel_layout() const { return channel_layout_; }
+  int sample_rate_hz() const { return sample_rate_hz_; }
+
+  void set_absolute_capture_timestamp_ms(
+      int64_t absolute_capture_time_stamp_ms) {
+    absolute_capture_timestamp_ms_ = absolute_capture_time_stamp_ms;
+  }
+
+  absl::optional<int64_t> absolute_capture_timestamp_ms() const {
+    return absolute_capture_timestamp_ms_;
+  }
+
+  // RTP timestamp of the first sample in the AudioFrame.
+  uint32_t timestamp_ = 0;
+  // Time since the first frame in milliseconds.
+  // -1 represents an uninitialized value.
+  int64_t elapsed_time_ms_ = -1;
+  // NTP time of the estimated capture time in local timebase in milliseconds.
+  // -1 represents an uninitialized value.
+  int64_t ntp_time_ms_ = -1;
+  size_t samples_per_channel_ = 0;
+  int sample_rate_hz_ = 0;
+  size_t num_channels_ = 0;
+  ChannelLayout channel_layout_ = CHANNEL_LAYOUT_NONE;
+  SpeechType speech_type_ = kUndefined;
+  VADActivity vad_activity_ = kVadUnknown;
+  // Monotonically increasing timestamp intended for profiling of audio frames.
+  // Typically used for measuring elapsed time between two different points in
+  // the audio path. No lock is used to save resources and we are thread safe
+  // by design.
+  // TODO(nisse@webrtc.org): consider using absl::optional.
+  int64_t profile_timestamp_ms_ = 0;
+
+  // Information about packets used to assemble this audio frame. This is needed
+  // by |SourceTracker| when the frame is delivered to the RTCRtpReceiver's
+  // MediaStreamTrack, in order to implement getContributingSources(). See:
+  // https://w3c.github.io/webrtc-pc/#dom-rtcrtpreceiver-getcontributingsources
+  //
+  // TODO(bugs.webrtc.org/10757):
+  //   Note that this information might not be fully accurate since we currently
+  //   don't have a proper way to track it across the audio sync buffer. The
+  //   sync buffer is the small sample-holding buffer located after the audio
+  //   decoder and before where samples are assembled into output frames.
+  //
+  // |RtpPacketInfos| may also be empty if the audio samples did not come from
+  // RTP packets. E.g. if the audio were locally generated by packet loss
+  // concealment, comfort noise generation, etc.
+  RtpPacketInfos packet_infos_;
+
+ private:
+  // A permanently zeroed out buffer to represent muted frames. This is a
+  // header-only class, so the only way to avoid creating a separate empty
+  // buffer per translation unit is to wrap a static in an inline function.
+  static const int16_t* empty_data();
+
+  int16_t data_[kMaxDataSizeSamples];
+  bool muted_ = true;
+
+  // Absolute capture timestamp when this audio frame was originally captured.
+  // This is only valid for audio frames captured on this machine. The absolute
+  // capture timestamp of a received frame is found in |packet_infos_|.
+  // This timestamp MUST be based on the same clock as rtc::TimeMillis().
+  absl::optional<int64_t> absolute_capture_timestamp_ms_;
+
+  RTC_DISALLOW_COPY_AND_ASSIGN(AudioFrame);
+};
+
+}  // namespace webrtc
+
+#endif  // API_AUDIO_AUDIO_FRAME_H_