mirror of
https://github.com/mollyim/webrtc.git
synced 2025-05-13 05:40:42 +01:00
3723433d2f
Required logic to query the min value of a SampleCounter along with some additions to the existing test cases Bug: webrtc:15580 Change-Id: I46afb30ad130f17f9e68ebc794b6935187bb2479 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/323900 Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org> Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org> Reviewed-by: Harald Alvestrand <hta@webrtc.org> Cr-Commit-Position: refs/heads/main@{#40956}
118 lines
3.4 KiB
C++
118 lines
3.4 KiB
C++
/*
|
|
* 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.
|
|
*/
|
|
|
|
#include "rtc_base/numerics/sample_counter.h"
|
|
|
|
#include <limits>
|
|
|
|
#include "rtc_base/checks.h"
|
|
#include "rtc_base/numerics/safe_conversions.h"
|
|
|
|
namespace rtc {
|
|
|
|
SampleCounter::SampleCounter() = default;
|
|
SampleCounter::~SampleCounter() = default;
|
|
|
|
void SampleCounter::Add(int sample) {
|
|
if (sum_ > 0) {
|
|
RTC_DCHECK_LE(sample, std::numeric_limits<int64_t>::max() - sum_);
|
|
} else {
|
|
RTC_DCHECK_GE(sample, std::numeric_limits<int64_t>::min() - sum_);
|
|
}
|
|
sum_ += sample;
|
|
++num_samples_;
|
|
if (!max_ || sample > *max_) {
|
|
max_ = sample;
|
|
}
|
|
if (!min_ || sample < *min_) {
|
|
min_ = sample;
|
|
}
|
|
}
|
|
|
|
void SampleCounter::Add(const SampleCounter& other) {
|
|
if (sum_ > 0) {
|
|
RTC_DCHECK_LE(other.sum_, std::numeric_limits<int64_t>::max() - sum_);
|
|
} else {
|
|
RTC_DCHECK_GE(other.sum_, std::numeric_limits<int64_t>::min() - sum_);
|
|
}
|
|
sum_ += other.sum_;
|
|
RTC_DCHECK_LE(other.num_samples_,
|
|
std::numeric_limits<int64_t>::max() - num_samples_);
|
|
num_samples_ += other.num_samples_;
|
|
if (other.max_ && (!max_ || *max_ < *other.max_))
|
|
max_ = other.max_;
|
|
if (other.min_ && (!min_ || *min_ > *other.min_))
|
|
min_ = other.min_;
|
|
}
|
|
|
|
absl::optional<int> SampleCounter::Avg(int64_t min_required_samples) const {
|
|
RTC_DCHECK_GT(min_required_samples, 0);
|
|
if (num_samples_ < min_required_samples)
|
|
return absl::nullopt;
|
|
return rtc::dchecked_cast<int>(sum_ / num_samples_);
|
|
}
|
|
|
|
absl::optional<int> SampleCounter::Max() const {
|
|
return max_;
|
|
}
|
|
|
|
absl::optional<int> SampleCounter::Min() const {
|
|
return min_;
|
|
}
|
|
|
|
absl::optional<int64_t> SampleCounter::Sum(int64_t min_required_samples) const {
|
|
RTC_DCHECK_GT(min_required_samples, 0);
|
|
if (num_samples_ < min_required_samples)
|
|
return absl::nullopt;
|
|
return sum_;
|
|
}
|
|
|
|
int64_t SampleCounter::NumSamples() const {
|
|
return num_samples_;
|
|
}
|
|
|
|
void SampleCounter::Reset() {
|
|
*this = {};
|
|
}
|
|
|
|
SampleCounterWithVariance::SampleCounterWithVariance() = default;
|
|
SampleCounterWithVariance::~SampleCounterWithVariance() = default;
|
|
|
|
absl::optional<int64_t> SampleCounterWithVariance::Variance(
|
|
int64_t min_required_samples) const {
|
|
RTC_DCHECK_GT(min_required_samples, 0);
|
|
if (num_samples_ < min_required_samples)
|
|
return absl::nullopt;
|
|
// E[(x-mean)^2] = E[x^2] - mean^2
|
|
int64_t mean = sum_ / num_samples_;
|
|
return sum_squared_ / num_samples_ - mean * mean;
|
|
}
|
|
|
|
void SampleCounterWithVariance::Add(int sample) {
|
|
SampleCounter::Add(sample);
|
|
// Prevent overflow in squaring.
|
|
RTC_DCHECK_GT(sample, std::numeric_limits<int32_t>::min());
|
|
RTC_DCHECK_LE(int64_t{sample} * sample,
|
|
std::numeric_limits<int64_t>::max() - sum_squared_);
|
|
sum_squared_ += int64_t{sample} * sample;
|
|
}
|
|
|
|
void SampleCounterWithVariance::Add(const SampleCounterWithVariance& other) {
|
|
SampleCounter::Add(other);
|
|
RTC_DCHECK_LE(other.sum_squared_,
|
|
std::numeric_limits<int64_t>::max() - sum_squared_);
|
|
sum_squared_ += other.sum_squared_;
|
|
}
|
|
|
|
void SampleCounterWithVariance::Reset() {
|
|
*this = {};
|
|
}
|
|
|
|
} // namespace rtc
|