136 lines
4.3 KiB
C++
136 lines
4.3 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 "call/rtp_bitrate_configurator.h"
|
|
|
|
#include <algorithm>
|
|
|
|
#include "rtc_base/checks.h"
|
|
|
|
namespace {
|
|
|
|
// Returns its smallest positive argument. If neither argument is positive,
|
|
// returns an arbitrary nonpositive value.
|
|
int MinPositive(int a, int b) {
|
|
if (a <= 0) {
|
|
return b;
|
|
}
|
|
if (b <= 0) {
|
|
return a;
|
|
}
|
|
return std::min(a, b);
|
|
}
|
|
|
|
} // namespace
|
|
|
|
namespace webrtc {
|
|
RtpBitrateConfigurator::RtpBitrateConfigurator(
|
|
const BitrateConstraints& bitrate_config)
|
|
: bitrate_config_(bitrate_config), base_bitrate_config_(bitrate_config) {
|
|
RTC_DCHECK_GE(bitrate_config.min_bitrate_bps, 0);
|
|
RTC_DCHECK_GE(bitrate_config.start_bitrate_bps,
|
|
bitrate_config.min_bitrate_bps);
|
|
if (bitrate_config.max_bitrate_bps != -1) {
|
|
RTC_DCHECK_GE(bitrate_config.max_bitrate_bps,
|
|
bitrate_config.start_bitrate_bps);
|
|
}
|
|
}
|
|
|
|
RtpBitrateConfigurator::~RtpBitrateConfigurator() = default;
|
|
|
|
BitrateConstraints RtpBitrateConfigurator::GetConfig() const {
|
|
return bitrate_config_;
|
|
}
|
|
|
|
absl::optional<BitrateConstraints>
|
|
RtpBitrateConfigurator::UpdateWithSdpParameters(
|
|
const BitrateConstraints& bitrate_config) {
|
|
RTC_DCHECK_GE(bitrate_config.min_bitrate_bps, 0);
|
|
RTC_DCHECK_NE(bitrate_config.start_bitrate_bps, 0);
|
|
if (bitrate_config.max_bitrate_bps != -1) {
|
|
RTC_DCHECK_GT(bitrate_config.max_bitrate_bps, 0);
|
|
}
|
|
|
|
absl::optional<int> new_start;
|
|
// Only update the "start" bitrate if it's set, and different from the old
|
|
// value. In practice, this value comes from the x-google-start-bitrate codec
|
|
// parameter in SDP, and setting the same remote description twice shouldn't
|
|
// restart bandwidth estimation.
|
|
if (bitrate_config.start_bitrate_bps != -1 &&
|
|
bitrate_config.start_bitrate_bps !=
|
|
base_bitrate_config_.start_bitrate_bps) {
|
|
new_start.emplace(bitrate_config.start_bitrate_bps);
|
|
}
|
|
base_bitrate_config_ = bitrate_config;
|
|
return UpdateConstraints(new_start);
|
|
}
|
|
|
|
absl::optional<BitrateConstraints>
|
|
RtpBitrateConfigurator::UpdateWithClientPreferences(
|
|
const BitrateSettings& bitrate_mask) {
|
|
bitrate_config_mask_ = bitrate_mask;
|
|
return UpdateConstraints(bitrate_mask.start_bitrate_bps);
|
|
}
|
|
|
|
// Relay cap can change only max bitrate.
|
|
absl::optional<BitrateConstraints> RtpBitrateConfigurator::UpdateWithRelayCap(
|
|
DataRate cap) {
|
|
if (cap.IsFinite()) {
|
|
RTC_DCHECK(!cap.IsZero());
|
|
}
|
|
max_bitrate_over_relay_ = cap;
|
|
return UpdateConstraints(absl::nullopt);
|
|
}
|
|
|
|
absl::optional<BitrateConstraints> RtpBitrateConfigurator::UpdateConstraints(
|
|
const absl::optional<int>& new_start) {
|
|
BitrateConstraints updated;
|
|
updated.min_bitrate_bps =
|
|
std::max(bitrate_config_mask_.min_bitrate_bps.value_or(0),
|
|
base_bitrate_config_.min_bitrate_bps);
|
|
|
|
updated.max_bitrate_bps =
|
|
MinPositive(bitrate_config_mask_.max_bitrate_bps.value_or(-1),
|
|
base_bitrate_config_.max_bitrate_bps);
|
|
updated.max_bitrate_bps =
|
|
MinPositive(updated.max_bitrate_bps, max_bitrate_over_relay_.bps_or(-1));
|
|
|
|
// If the combined min ends up greater than the combined max, the max takes
|
|
// priority.
|
|
if (updated.max_bitrate_bps != -1 &&
|
|
updated.min_bitrate_bps > updated.max_bitrate_bps) {
|
|
updated.min_bitrate_bps = updated.max_bitrate_bps;
|
|
}
|
|
|
|
// If there is nothing to update (min/max unchanged, no new bandwidth
|
|
// estimation start value), return early.
|
|
if (updated.min_bitrate_bps == bitrate_config_.min_bitrate_bps &&
|
|
updated.max_bitrate_bps == bitrate_config_.max_bitrate_bps &&
|
|
!new_start) {
|
|
return absl::nullopt;
|
|
}
|
|
|
|
if (new_start) {
|
|
// Clamp start by min and max.
|
|
updated.start_bitrate_bps = MinPositive(
|
|
std::max(*new_start, updated.min_bitrate_bps), updated.max_bitrate_bps);
|
|
} else {
|
|
updated.start_bitrate_bps = -1;
|
|
}
|
|
BitrateConstraints config_to_return = updated;
|
|
if (!new_start) {
|
|
updated.start_bitrate_bps = bitrate_config_.start_bitrate_bps;
|
|
}
|
|
bitrate_config_ = updated;
|
|
return config_to_return;
|
|
}
|
|
|
|
} // namespace webrtc
|