blob: c9032773a6b6f9577375f248653cb5343ff64175 [file] [log] [blame]
* Copyright (c) 2021 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 <memory>
#include <vector>
#include "absl/types/optional.h"
namespace webrtc {
// A circular buffer to store frame-wise `Level` items for clipping prediction.
// The current implementation is not optimized for large buffer lengths.
class ClippingPredictorLevelBuffer {
struct Level {
float average;
float max;
bool operator==(const Level& level) const;
// Recommended maximum capacity. It is possible to create a buffer with a
// larger capacity, but the implementation is not optimized for large values.
static constexpr int kMaxCapacity = 100;
// Ctor. Sets the buffer capacity to max(1, `capacity`) and logs a warning
// message if the capacity is greater than `kMaxCapacity`.
explicit ClippingPredictorLevelBuffer(int capacity);
~ClippingPredictorLevelBuffer() {}
ClippingPredictorLevelBuffer(const ClippingPredictorLevelBuffer&) = delete;
ClippingPredictorLevelBuffer& operator=(const ClippingPredictorLevelBuffer&) =
void Reset();
// Returns the current number of items stored in the buffer.
int Size() const { return size_; }
// Returns the capacity of the buffer.
int Capacity() const { return data_.size(); }
// Adds a `level` item into the circular buffer `data_`. Stores at most
// `Capacity()` items. If more items are pushed, the new item replaces the
// least recently pushed item.
void Push(Level level);
// If at least `num_items` + `delay` items have been pushed, returns the
// average and maximum value for the `num_items` most recently pushed items
// from `delay` to `delay` - `num_items` (a delay equal to zero corresponds
// to the most recently pushed item). The value of `delay` is limited to
// [0, N] and `num_items` to [1, M] where N + M is the capacity of the buffer.
absl::optional<Level> ComputePartialMetrics(int delay, int num_items) const;
int tail_;
int size_;
std::vector<Level> data_;
} // namespace webrtc