1 files changed, 61 insertions, 0 deletions
diff --git a/third_party/libwebrtc/modules/video_coding/timing/decode_time_percentile_filter.cc b/third_party/libwebrtc/modules/video_coding/timing/decode_time_percentile_filter.cc
new file mode 100644
index 0000000000..e40ab5c6ce
--- /dev/null
+++ b/third_party/libwebrtc/modules/video_coding/timing/decode_time_percentile_filter.cc
@@ -0,0 +1,61 @@
+/*
+ *  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.
+ */
+
+#include "modules/video_coding/timing/decode_time_percentile_filter.h"
+
+#include <cstdint>
+
+namespace webrtc {
+
+namespace {
+
+// The first kIgnoredSampleCount samples will be ignored.
+const int kIgnoredSampleCount = 5;
+// Return the `kPercentile` value in RequiredDecodeTimeMs().
+const float kPercentile = 0.95f;
+// The window size in ms.
+const int64_t kTimeLimitMs = 10000;
+
+}  // anonymous namespace
+
+DecodeTimePercentileFilter::DecodeTimePercentileFilter()
+    : ignored_sample_count_(0), filter_(kPercentile) {}
+DecodeTimePercentileFilter::~DecodeTimePercentileFilter() = default;
+
+void DecodeTimePercentileFilter::AddTiming(int64_t decode_time_ms,
+                                           int64_t now_ms) {
+  // Ignore the first `kIgnoredSampleCount` samples.
+  if (ignored_sample_count_ < kIgnoredSampleCount) {
+    ++ignored_sample_count_;
+    return;
+  }
+
+  // Insert new decode time value.
+  filter_.Insert(decode_time_ms);
+  history_.emplace(decode_time_ms, now_ms);
+
+  // Pop old decode time values.
+  while (!history_.empty() &&
+         now_ms - history_.front().sample_time_ms > kTimeLimitMs) {
+    filter_.Erase(history_.front().decode_time_ms);
+    history_.pop();
+  }
+}
+
+// Get the 95th percentile observed decode time within a time window.
+int64_t DecodeTimePercentileFilter::RequiredDecodeTimeMs() const {
+  return filter_.GetPercentileValue();
+}
+
+DecodeTimePercentileFilter::Sample::Sample(int64_t decode_time_ms,
+                                           int64_t sample_time_ms)
+    : decode_time_ms(decode_time_ms), sample_time_ms(sample_time_ms) {}
+
+}  // namespace webrtc