Unify the FillAudioEncoderTimeSeries with existing processing functions.

webrtc/tools/event_log_visualizer/analyzer.cc

Index: webrtc/tools/event_log_visualizer/analyzer.cc
diff --git a/webrtc/tools/event_log_visualizer/analyzer.cc b/webrtc/tools/event_log_visualizer/analyzer.cc
index 15b3e821b843f9647f92e0be053d68025964f4b2..47528f76c85ac9899a74beba1b41ee3b7896a19b 100644
--- a/webrtc/tools/event_log_visualizer/analyzer.cc
+++ b/webrtc/tools/event_log_visualizer/analyzer.cc
@@ -133,128 +133,124 @@ constexpr float kRightMargin = 0.02f;
 constexpr float kBottomMargin = 0.02f;
 constexpr float kTopMargin = 0.05f;
 
-class PacketSizeBytes {
- public:
-  using DataType = LoggedRtpPacket;
-  using ResultType = size_t;
-  size_t operator()(const LoggedRtpPacket& packet) {
-    return packet.total_length;
+rtc::Optional<double> NetworkDelayDiff_AbsSendTime(
+    const LoggedRtpPacket& old_packet,
+    const LoggedRtpPacket& new_packet) {
+  if (old_packet.header.extension.hasAbsoluteSendTime &&
+      new_packet.header.extension.hasAbsoluteSendTime) {
+    int64_t send_time_diff = WrappingDifference(
+        new_packet.header.extension.absoluteSendTime,
+        old_packet.header.extension.absoluteSendTime, 1ul << 24);
+    int64_t recv_time_diff = new_packet.timestamp - old_packet.timestamp;
+    double delay_change_us =
+        recv_time_diff - AbsSendTimeToMicroseconds(send_time_diff);
+    return rtc::Optional<double>(delay_change_us / 1000);
+  } else {
+    return rtc::Optional<double>();
   }
-};
+}
 
-class SequenceNumberDiff {
- public:
-  using DataType = LoggedRtpPacket;
-  using ResultType = int64_t;
-  int64_t operator()(const LoggedRtpPacket& old_packet,
-                     const LoggedRtpPacket& new_packet) {
-    return WrappingDifference(new_packet.header.sequenceNumber,
-                              old_packet.header.sequenceNumber, 1ul << 16);
+rtc::Optional<double> NetworkDelayDiff_CaptureTime(
+    const LoggedRtpPacket& old_packet,
+    const LoggedRtpPacket& new_packet) {
+  int64_t send_time_diff = WrappingDifference(
+      new_packet.header.timestamp, old_packet.header.timestamp, 1ull << 32);
+  int64_t recv_time_diff = new_packet.timestamp - old_packet.timestamp;
+
+  const double kVideoSampleRate = 90000;
+  // TODO(terelius): We treat all streams as video for now, even though
+  // audio might be sampled at e.g. 16kHz, because it is really difficult to
+  // figure out the true sampling rate of a stream. The effect is that the
+  // delay will be scaled incorrectly for non-video streams.
+
+  double delay_change =
+      static_cast<double>(recv_time_diff) / 1000 -
+      static_cast<double>(send_time_diff) / kVideoSampleRate * 1000;
+  if (delay_change < -10000 || 10000 < delay_change) {
+    LOG(LS_WARNING) << "Very large delay change. Timestamps correct?";
+    LOG(LS_WARNING) << "Old capture time " << old_packet.header.timestamp
+                    << ", received time " << old_packet.timestamp;
+    LOG(LS_WARNING) << "New capture time " << new_packet.header.timestamp
+                    << ", received time " << new_packet.timestamp;
+    LOG(LS_WARNING) << "Receive time difference " << recv_time_diff << " = "
+                    << static_cast<double>(recv_time_diff) / 1000000 << "s";
+    LOG(LS_WARNING) << "Send time difference " << send_time_diff << " = "
+                    << static_cast<double>(send_time_diff) / kVideoSampleRate
+                    << "s";
   }
-};
-
-class NetworkDelayDiff {
- public:
-  class AbsSendTime {
-   public:
-    using DataType = LoggedRtpPacket;
-    using ResultType = double;
-    double operator()(const LoggedRtpPacket& old_packet,
-                      const LoggedRtpPacket& new_packet) {
-      if (old_packet.header.extension.hasAbsoluteSendTime &&
-          new_packet.header.extension.hasAbsoluteSendTime) {
-        int64_t send_time_diff = WrappingDifference(
-            new_packet.header.extension.absoluteSendTime,
-            old_packet.header.extension.absoluteSendTime, 1ul << 24);
-        int64_t recv_time_diff = new_packet.timestamp - old_packet.timestamp;
-        return static_cast<double>(recv_time_diff -
-                                   AbsSendTimeToMicroseconds(send_time_diff)) /
-               1000;
-      } else {
-        return 0;
-      }
-    }
-  };
-
-  class CaptureTime {
-   public:
-    using DataType = LoggedRtpPacket;
-    using ResultType = double;
-    double operator()(const LoggedRtpPacket& old_packet,
-                      const LoggedRtpPacket& new_packet) {
-      int64_t send_time_diff = WrappingDifference(
-          new_packet.header.timestamp, old_packet.header.timestamp, 1ull << 32);
-      int64_t recv_time_diff = new_packet.timestamp - old_packet.timestamp;
-
-      const double kVideoSampleRate = 90000;
-      // TODO(terelius): We treat all streams as video for now, even though
-      // audio might be sampled at e.g. 16kHz, because it is really difficult to
-      // figure out the true sampling rate of a stream. The effect is that the
-      // delay will be scaled incorrectly for non-video streams.
-
-      double delay_change =
-          static_cast<double>(recv_time_diff) / 1000 -
-          static_cast<double>(send_time_diff) / kVideoSampleRate * 1000;
-      if (delay_change < -10000 || 10000 < delay_change) {
-        LOG(LS_WARNING) << "Very large delay change. Timestamps correct?";
-        LOG(LS_WARNING) << "Old capture time " << old_packet.header.timestamp
-                        << ", received time " << old_packet.timestamp;
-        LOG(LS_WARNING) << "New capture time " << new_packet.header.timestamp
-                        << ", received time " << new_packet.timestamp;
-        LOG(LS_WARNING) << "Receive time difference " << recv_time_diff << " = "
-                        << static_cast<double>(recv_time_diff) / 1000000 << "s";
-        LOG(LS_WARNING) << "Send time difference " << send_time_diff << " = "
-                        << static_cast<double>(send_time_diff) /
-                               kVideoSampleRate
-                        << "s";
-      }
-      return delay_change;
-    }
-  };
-};
+  return rtc::Optional<double>(delay_change);
+}
 
-template <typename Extractor>
-class Accumulated {
- public:
-  using DataType = typename Extractor::DataType;
-  using ResultType = typename Extractor::ResultType;
-  ResultType operator()(const DataType& old_packet,
-                        const DataType& new_packet) {
-    sum += extract(old_packet, new_packet);
-    return sum;
+// For each element in data, use |get_y()| to extract a y-coordinate and
+// store the result in a TimeSeries.
+template <typename DataType>
+void ProcessPoints(
+    rtc::FunctionView<rtc::Optional<float>(const DataType&)> get_y,
+    const std::vector<DataType>& data,
+    uint64_t begin_time,
+    TimeSeries* result) {
+  for (size_t i = 0; i < data.size(); i++) {
+    float x = static_cast<float>(data[i].timestamp - begin_time) / 1000000;
+    rtc::Optional<float> y = get_y(data[i]);
+    if (y)
+      result->points.emplace_back(x, *y);
   }
+}
 
- private:
-  Extractor extract;
-  ResultType sum = 0;
-};
+// For each pair of adjacent elements in |data|, use |get_y| to extract a
+// y-coordinate and store the result in a TimeSeries. Note that the x-coordinate
+// will be the time of the second element in the pair.
+template <typename DataType, typename ResultType>
+void ProcessPairs(
+    rtc::FunctionView<rtc::Optional<ResultType>(const DataType&,
+                                                const DataType&)> get_y,
+    const std::vector<DataType>& data,
+    uint64_t begin_time,
+    TimeSeries* result) {
+  for (size_t i = 1; i < data.size(); i++) {
+    float x = static_cast<float>(data[i].timestamp - begin_time) / 1000000;
+    rtc::Optional<ResultType> y = get_y(data[i - 1], data[i]);
+    if (y)
+      result->points.emplace_back(x, static_cast<float>(*y));
+  }
+}
 
-// For each element in data, use |Extractor| to extract a y-coordinate and
+// For each element in data, use |extract()| to extract a y-coordinate and
 // store the result in a TimeSeries.
-template <typename Extractor>
-void Pointwise(const std::vector<typename Extractor::DataType>& data,
-               uint64_t begin_time,
-               TimeSeries* result) {
-  Extractor extract;
+template <typename DataType, typename ResultType>
+void AccumulatePoints(
+    rtc::FunctionView<rtc::Optional<ResultType>(const DataType&)> extract,
+    const std::vector<DataType>& data,
+    uint64_t begin_time,
+    TimeSeries* result) {
+  ResultType sum = 0;
   for (size_t i = 0; i < data.size(); i++) {
     float x = static_cast<float>(data[i].timestamp - begin_time) / 1000000;
-    float y = extract(data[i]);
-    result->points.emplace_back(x, y);
+    rtc::Optional<ResultType> y = extract(data[i]);
+    if (y) {
+      sum += *y;
+      result->points.emplace_back(x, static_cast<float>(sum));
+    }
   }
 }
 
-// For each pair of adjacent elements in |data|, use |Extractor| to extract a
+// For each pair of adjacent elements in |data|, use |extract()| to extract a
 // y-coordinate and store the result in a TimeSeries. Note that the x-coordinate
 // will be the time of the second element in the pair.
-template <typename Extractor>
-void Pairwise(const std::vector<typename Extractor::DataType>& data,
-              uint64_t begin_time,
-              TimeSeries* result) {
-  Extractor extract;
+template <typename DataType, typename ResultType>
+void AccumulatePairs(
+    rtc::FunctionView<rtc::Optional<ResultType>(const DataType&,
+                                                const DataType&)> extract,
+    const std::vector<DataType>& data,
+    uint64_t begin_time,
+    TimeSeries* result) {
+  ResultType sum = 0;
   for (size_t i = 1; i < data.size(); i++) {
     float x = static_cast<float>(data[i].timestamp - begin_time) / 1000000;
-    float y = extract(data[i - 1], data[i]);
-    result->points.emplace_back(x, y);
+    rtc::Optional<ResultType> y = extract(data[i - 1], data[i]);
+    if (y)
+      sum += *y;
+    result->points.emplace_back(x, static_cast<float>(sum));
   }
 }
 
@@ -262,33 +258,37 @@ void Pairwise(const std::vector<typename Extractor::DataType>& data,
 // A data point is generated every |step| microseconds from |begin_time|
 // to |end_time|. The value of each data point is the average of the data
 // during the preceeding |window_duration_us| microseconds.
-template <typename Extractor>
-void MovingAverage(const std::vector<typename Extractor::DataType>& data,
-                   uint64_t begin_time,
-                   uint64_t end_time,
-                   uint64_t window_duration_us,
-                   uint64_t step,
-                   float y_scaling,
-                   webrtc::plotting::TimeSeries* result) {
+template <typename DataType, typename ResultType>
+void MovingAverage(
+    rtc::FunctionView<rtc::Optional<ResultType>(const DataType&)> extract,
+    const std::vector<DataType>& data,
+    uint64_t begin_time,
+    uint64_t end_time,
+    uint64_t window_duration_us,
+    uint64_t step,
+    webrtc::plotting::TimeSeries* result) {
   size_t window_index_begin = 0;
   size_t window_index_end = 0;
-  typename Extractor::ResultType sum_in_window = 0;
-  Extractor extract;
+  ResultType sum_in_window = 0;
 
   for (uint64_t t = begin_time; t < end_time + step; t += step) {
     while (window_index_end < data.size() &&
            data[window_index_end].timestamp < t) {
-      sum_in_window += extract(data[window_index_end]);
+      rtc::Optional<ResultType> value = extract(data[window_index_end]);
+      if (value)
+        sum_in_window += *value;
       ++window_index_end;
     }
     while (window_index_begin < data.size() &&
            data[window_index_begin].timestamp < t - window_duration_us) {
-      sum_in_window -= extract(data[window_index_begin]);
+      rtc::Optional<ResultType> value = extract(data[window_index_begin]);
+      if (value)
+        sum_in_window -= *value;
       ++window_index_begin;
     }
     float window_duration_s = static_cast<float>(window_duration_us) / 1000000;
     float x = static_cast<float>(t - begin_time) / 1000000;
-    float y = sum_in_window / window_duration_s * y_scaling;
+    float y = sum_in_window / window_duration_s;
     result->points.emplace_back(x, y);
   }
 }
@@ -562,21 +562,6 @@ std::string EventLogAnalyzer::GetStreamName(StreamId stream_id) const {
   return name.str();
 }
 
-void EventLogAnalyzer::FillAudioEncoderTimeSeries(
-    Plot* plot,
-    rtc::FunctionView<rtc::Optional<float>(
-        const AudioNetworkAdaptationEvent& ana_event)> get_y) const {
-  plot->series_list_.push_back(TimeSeries());
-  plot->series_list_.back().style = LINE_DOT_GRAPH;
-  for (auto& ana_event : audio_network_adaptation_events_) {
-    rtc::Optional<float> y = get_y(ana_event);
-    if (y) {
-      float x = static_cast<float>(ana_event.timestamp - begin_time_) / 1000000;
-      plot->series_list_.back().points.emplace_back(x, *y);
-    }
-  }
-}
-
 void EventLogAnalyzer::CreatePacketGraph(PacketDirection desired_direction,
                                          Plot* plot) {
   for (auto& kv : rtp_packets_) {
@@ -591,7 +576,11 @@ void EventLogAnalyzer::CreatePacketGraph(PacketDirection desired_direction,
     TimeSeries time_series;
     time_series.label = GetStreamName(stream_id);
     time_series.style = BAR_GRAPH;
-    Pointwise<PacketSizeBytes>(packet_stream, begin_time_, &time_series);
+    ProcessPoints<LoggedRtpPacket>(
+        [](const LoggedRtpPacket& packet) -> rtc::Optional<float> {
+          return rtc::Optional<float>(packet.total_length);
+        },
+        packet_stream, begin_time_, &time_series);
     plot->series_list_.push_back(std::move(time_series));
   }
 
@@ -737,7 +726,15 @@ void EventLogAnalyzer::CreateSequenceNumberGraph(Plot* plot) {
     TimeSeries time_series;
     time_series.label = GetStreamName(stream_id);
     time_series.style = BAR_GRAPH;
-    Pairwise<SequenceNumberDiff>(packet_stream, begin_time_, &time_series);
+    ProcessPairs<LoggedRtpPacket, float>(
+        [](const LoggedRtpPacket& old_packet,
+           const LoggedRtpPacket& new_packet) {
+          int64_t diff =
+              WrappingDifference(new_packet.header.sequenceNumber,
+                                 old_packet.header.sequenceNumber, 1ul << 16);
+          return rtc::Optional<float>(diff);
+        },
+        packet_stream, begin_time_, &time_series);
     plot->series_list_.push_back(std::move(time_series));
   }
 
@@ -821,15 +818,17 @@ void EventLogAnalyzer::CreateDelayChangeGraph(Plot* plot) {
     TimeSeries capture_time_data;
     capture_time_data.label = GetStreamName(stream_id) + " capture-time";
     capture_time_data.style = BAR_GRAPH;
-    Pairwise<NetworkDelayDiff::CaptureTime>(packet_stream, begin_time_,
-                                            &capture_time_data);
+    ProcessPairs<LoggedRtpPacket, double>(NetworkDelayDiff_CaptureTime,
+                                          packet_stream, begin_time_,
+                                          &capture_time_data);
     plot->series_list_.push_back(std::move(capture_time_data));
 
     TimeSeries send_time_data;
     send_time_data.label = GetStreamName(stream_id) + " abs-send-time";
     send_time_data.style = BAR_GRAPH;
-    Pairwise<NetworkDelayDiff::AbsSendTime>(packet_stream, begin_time_,
-                                            &send_time_data);
+    ProcessPairs<LoggedRtpPacket, double>(NetworkDelayDiff_AbsSendTime,
+                                          packet_stream, begin_time_,
+                                          &send_time_data);
     plot->series_list_.push_back(std::move(send_time_data));
   }
 
@@ -854,15 +853,17 @@ void EventLogAnalyzer::CreateAccumulatedDelayChangeGraph(Plot* plot) {
     TimeSeries capture_time_data;
     capture_time_data.label = GetStreamName(stream_id) + " capture-time";
     capture_time_data.style = LINE_GRAPH;
-    Pairwise<Accumulated<NetworkDelayDiff::CaptureTime>>(
-        packet_stream, begin_time_, &capture_time_data);
+    AccumulatePairs<LoggedRtpPacket, double>(NetworkDelayDiff_CaptureTime,
+                                             packet_stream, begin_time_,
+                                             &capture_time_data);
     plot->series_list_.push_back(std::move(capture_time_data));
 
     TimeSeries send_time_data;
     send_time_data.label = GetStreamName(stream_id) + " abs-send-time";
     send_time_data.style = LINE_GRAPH;
-    Pairwise<Accumulated<NetworkDelayDiff::AbsSendTime>>(
-        packet_stream, begin_time_, &send_time_data);
+    AccumulatePairs<LoggedRtpPacket, double>(NetworkDelayDiff_AbsSendTime,
+                                             packet_stream, begin_time_,
+                                             &send_time_data);
     plot->series_list_.push_back(std::move(send_time_data));
   }
 
@@ -986,10 +987,12 @@ void EventLogAnalyzer::CreateStreamBitrateGraph(
     TimeSeries time_series;
     time_series.label = GetStreamName(stream_id);
     time_series.style = LINE_GRAPH;
-    double bytes_to_kilobits = 8.0 / 1000;
-    MovingAverage<PacketSizeBytes>(packet_stream, begin_time_, end_time_,
-                                   window_duration_, step_, bytes_to_kilobits,
-                                   &time_series);
+    MovingAverage<LoggedRtpPacket, double>(
+        [](const LoggedRtpPacket& packet) {
+          return rtc::Optional<double>(packet.total_length * 8.0 / 1000.0);
+        },
+        packet_stream, begin_time_, end_time_, window_duration_, step_,
+        &time_series);
     plot->series_list_.push_back(std::move(time_series));
   }
 
@@ -1323,28 +1326,36 @@ void EventLogAnalyzer::CreateTimestampGraph(Plot* plot) {
 }
 
 void EventLogAnalyzer::CreateAudioEncoderTargetBitrateGraph(Plot* plot) {
-  FillAudioEncoderTimeSeries(
-      plot, [](const AudioNetworkAdaptationEvent& ana_event) {
+  plot->series_list_.push_back(TimeSeries());
+  plot->series_list_.back().style = LINE_DOT_GRAPH;
+  plot->series_list_.back().label = "Audio encoder target bitrate";
+  ProcessPoints<AudioNetworkAdaptationEvent>(
+      [](const AudioNetworkAdaptationEvent& ana_event) -> rtc::Optional<float> {
         if (ana_event.config.bitrate_bps)
           return rtc::Optional<float>(
               static_cast<float>(*ana_event.config.bitrate_bps));
         return rtc::Optional<float>();
-      });
-  plot->series_list_.back().label = "Audio encoder target bitrate";
+      },
+      audio_network_adaptation_events_, begin_time_,
+      &plot->series_list_.back());
   plot->SetXAxis(0, call_duration_s_, "Time (s)", kLeftMargin, kRightMargin);
   plot->SetSuggestedYAxis(0, 1, "Bitrate (bps)", kBottomMargin, kTopMargin);
   plot->SetTitle("Reported audio encoder target bitrate");
 }
 
 void EventLogAnalyzer::CreateAudioEncoderFrameLengthGraph(Plot* plot) {
-  FillAudioEncoderTimeSeries(
-      plot, [](const AudioNetworkAdaptationEvent& ana_event) {
+  plot->series_list_.push_back(TimeSeries());
+  plot->series_list_.back().style = LINE_DOT_GRAPH;
+  plot->series_list_.back().label = "Audio encoder frame length";
+  ProcessPoints<AudioNetworkAdaptationEvent>(
+      [](const AudioNetworkAdaptationEvent& ana_event) {
         if (ana_event.config.frame_length_ms)
           return rtc::Optional<float>(
               static_cast<float>(*ana_event.config.frame_length_ms));
         return rtc::Optional<float>();
-      });
-  plot->series_list_.back().label = "Audio encoder frame length";
+      },
+      audio_network_adaptation_events_, begin_time_,
+      &plot->series_list_.back());
   plot->SetXAxis(0, call_duration_s_, "Time (s)", kLeftMargin, kRightMargin);
   plot->SetSuggestedYAxis(0, 1, "Frame length (ms)", kBottomMargin, kTopMargin);
   plot->SetTitle("Reported audio encoder frame length");
@@ -1352,14 +1363,18 @@ void EventLogAnalyzer::CreateAudioEncoderFrameLengthGraph(Plot* plot) {
 
 void EventLogAnalyzer::CreateAudioEncoderUplinkPacketLossFractionGraph(
     Plot* plot) {
-  FillAudioEncoderTimeSeries(
-      plot, [&](const AudioNetworkAdaptationEvent& ana_event) {
+  plot->series_list_.push_back(TimeSeries());
+  plot->series_list_.back().style = LINE_DOT_GRAPH;
+  plot->series_list_.back().label = "Audio encoder uplink packet loss fraction";
+  ProcessPoints<AudioNetworkAdaptationEvent>(
+      [](const AudioNetworkAdaptationEvent& ana_event) {
         if (ana_event.config.uplink_packet_loss_fraction)
           return rtc::Optional<float>(static_cast<float>(
               *ana_event.config.uplink_packet_loss_fraction));
         return rtc::Optional<float>();
-      });
-  plot->series_list_.back().label = "Audio encoder uplink packet loss fraction";
+      },
+      audio_network_adaptation_events_, begin_time_,
+      &plot->series_list_.back());
   plot->SetXAxis(0, call_duration_s_, "Time (s)", kLeftMargin, kRightMargin);
   plot->SetSuggestedYAxis(0, 10, "Percent lost packets", kBottomMargin,
                           kTopMargin);
@@ -1367,42 +1382,54 @@ void EventLogAnalyzer::CreateAudioEncoderUplinkPacketLossFractionGraph(
 }
 
 void EventLogAnalyzer::CreateAudioEncoderEnableFecGraph(Plot* plot) {
-  FillAudioEncoderTimeSeries(
-      plot, [&](const AudioNetworkAdaptationEvent& ana_event) {
+  plot->series_list_.push_back(TimeSeries());
+  plot->series_list_.back().style = LINE_DOT_GRAPH;
+  plot->series_list_.back().label = "Audio encoder FEC";
+  ProcessPoints<AudioNetworkAdaptationEvent>(
+      [](const AudioNetworkAdaptationEvent& ana_event) {
         if (ana_event.config.enable_fec)
           return rtc::Optional<float>(
               static_cast<float>(*ana_event.config.enable_fec));
         return rtc::Optional<float>();
-      });
-  plot->series_list_.back().label = "Audio encoder FEC";
+      },
+      audio_network_adaptation_events_, begin_time_,
+      &plot->series_list_.back());
   plot->SetXAxis(0, call_duration_s_, "Time (s)", kLeftMargin, kRightMargin);
   plot->SetSuggestedYAxis(0, 1, "FEC (false/true)", kBottomMargin, kTopMargin);
   plot->SetTitle("Reported audio encoder FEC");
 }
 
 void EventLogAnalyzer::CreateAudioEncoderEnableDtxGraph(Plot* plot) {
-  FillAudioEncoderTimeSeries(
-      plot, [&](const AudioNetworkAdaptationEvent& ana_event) {
+  plot->series_list_.push_back(TimeSeries());
+  plot->series_list_.back().style = LINE_DOT_GRAPH;
+  plot->series_list_.back().label = "Audio encoder DTX";
+  ProcessPoints<AudioNetworkAdaptationEvent>(
+      [](const AudioNetworkAdaptationEvent& ana_event) {
         if (ana_event.config.enable_dtx)
           return rtc::Optional<float>(
               static_cast<float>(*ana_event.config.enable_dtx));
         return rtc::Optional<float>();
-      });
-  plot->series_list_.back().label = "Audio encoder DTX";
+      },
+      audio_network_adaptation_events_, begin_time_,
+      &plot->series_list_.back());
   plot->SetXAxis(0, call_duration_s_, "Time (s)", kLeftMargin, kRightMargin);
   plot->SetSuggestedYAxis(0, 1, "DTX (false/true)", kBottomMargin, kTopMargin);
   plot->SetTitle("Reported audio encoder DTX");
 }
 
 void EventLogAnalyzer::CreateAudioEncoderNumChannelsGraph(Plot* plot) {
-  FillAudioEncoderTimeSeries(
-      plot, [&](const AudioNetworkAdaptationEvent& ana_event) {
+  plot->series_list_.push_back(TimeSeries());
+  plot->series_list_.back().style = LINE_DOT_GRAPH;
+  plot->series_list_.back().label = "Audio encoder number of channels";
+  ProcessPoints<AudioNetworkAdaptationEvent>(
+      [](const AudioNetworkAdaptationEvent& ana_event) {
         if (ana_event.config.num_channels)
           return rtc::Optional<float>(
               static_cast<float>(*ana_event.config.num_channels));
         return rtc::Optional<float>();
-      });
-  plot->series_list_.back().label = "Audio encoder number of channels";
+      },
+      audio_network_adaptation_events_, begin_time_,
+      &plot->series_list_.back());
   plot->SetXAxis(0, call_duration_s_, "Time (s)", kLeftMargin, kRightMargin);
   plot->SetSuggestedYAxis(0, 1, "Number of channels (1 (mono)/2 (stereo))",
                           kBottomMargin, kTopMargin);