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/*
* Copyright 2013 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 "sdk/media_constraints.h"
#include "absl/types/optional.h"
#include "api/peer_connection_interface.h"
namespace webrtc {
namespace {
// Find the highest-priority instance of the T-valued constraint named by
// `key` and return its value as `value`. `constraints` can be null.
// If `mandatory_constraints` is non-null, it is incremented if the key appears
// among the mandatory constraints.
// Returns true if the key was found and has a valid value for type T.
// If the key appears multiple times as an optional constraint, appearances
// after the first are ignored.
// Note: Because this uses FindFirst, repeated optional constraints whose
// first instance has an unrecognized value are not handled precisely in
// accordance with the specification.
template <typename T>
bool FindConstraint(const MediaConstraints* constraints,
const std::string& key,
T* value,
size_t* mandatory_constraints) {
std::string string_value;
if (!FindConstraint(constraints, key, &string_value, mandatory_constraints)) {
return false;
}
return rtc::FromString(string_value, value);
}
// Specialization for std::string, since a string doesn't need conversion.
template <>
bool FindConstraint(const MediaConstraints* constraints,
const std::string& key,
std::string* value,
size_t* mandatory_constraints) {
if (!constraints) {
return false;
}
if (constraints->GetMandatory().FindFirst(key, value)) {
if (mandatory_constraints) {
++*mandatory_constraints;
}
return true;
}
if (constraints->GetOptional().FindFirst(key, value)) {
return true;
}
return false;
}
bool FindConstraint(const MediaConstraints* constraints,
const std::string& key,
bool* value,
size_t* mandatory_constraints) {
return FindConstraint<bool>(constraints, key, value, mandatory_constraints);
}
bool FindConstraint(const MediaConstraints* constraints,
const std::string& key,
int* value,
size_t* mandatory_constraints) {
return FindConstraint<int>(constraints, key, value, mandatory_constraints);
}
// Converts a constraint (mandatory takes precedence over optional) to an
// absl::optional.
template <typename T>
void ConstraintToOptional(const MediaConstraints* constraints,
const std::string& key,
absl::optional<T>* value_out) {
T value;
bool present = FindConstraint<T>(constraints, key, &value, nullptr);
if (present) {
*value_out = value;
}
}
} // namespace
const char MediaConstraints::kValueTrue[] = "true";
const char MediaConstraints::kValueFalse[] = "false";
// Constraints declared as static members in mediastreaminterface.h
// Audio constraints.
const char MediaConstraints::kGoogEchoCancellation[] = "googEchoCancellation";
const char MediaConstraints::kAutoGainControl[] = "googAutoGainControl";
const char MediaConstraints::kNoiseSuppression[] = "googNoiseSuppression";
const char MediaConstraints::kHighpassFilter[] = "googHighpassFilter";
const char MediaConstraints::kAudioMirroring[] = "googAudioMirroring";
const char MediaConstraints::kAudioNetworkAdaptorConfig[] =
"googAudioNetworkAdaptorConfig";
const char MediaConstraints::kInitAudioRecordingOnSend[] =
"InitAudioRecordingOnSend";
// Constraint keys for CreateOffer / CreateAnswer defined in W3C specification.
const char MediaConstraints::kOfferToReceiveAudio[] = "OfferToReceiveAudio";
const char MediaConstraints::kOfferToReceiveVideo[] = "OfferToReceiveVideo";
const char MediaConstraints::kVoiceActivityDetection[] =
"VoiceActivityDetection";
const char MediaConstraints::kIceRestart[] = "IceRestart";
// Google specific constraint for BUNDLE enable/disable.
const char MediaConstraints::kUseRtpMux[] = "googUseRtpMUX";
// Below constraints should be used during PeerConnection construction.
// Google-specific constraint keys.
const char MediaConstraints::kEnableDscp[] = "googDscp";
const char MediaConstraints::kEnableVideoSuspendBelowMinBitrate[] =
"googSuspendBelowMinBitrate";
const char MediaConstraints::kScreencastMinBitrate[] =
"googScreencastMinBitrate";
// TODO(ronghuawu): Remove once cpu overuse detection is stable.
const char MediaConstraints::kCpuOveruseDetection[] = "googCpuOveruseDetection";
const char MediaConstraints::kRawPacketizationForVideoEnabled[] =
"googRawPacketizationForVideoEnabled";
const char MediaConstraints::kNumSimulcastLayers[] = "googNumSimulcastLayers";
// Set `value` to the value associated with the first appearance of `key`, or
// return false if `key` is not found.
bool MediaConstraints::Constraints::FindFirst(const std::string& key,
std::string* value) const {
for (Constraints::const_iterator iter = begin(); iter != end(); ++iter) {
if (iter->key == key) {
*value = iter->value;
return true;
}
}
return false;
}
void CopyConstraintsIntoRtcConfiguration(
const MediaConstraints* constraints,
PeerConnectionInterface::RTCConfiguration* configuration) {
// Copy info from constraints into configuration, if present.
if (!constraints) {
return;
}
FindConstraint(constraints, MediaConstraints::kEnableDscp,
&configuration->media_config.enable_dscp, nullptr);
FindConstraint(constraints, MediaConstraints::kCpuOveruseDetection,
&configuration->media_config.video.enable_cpu_adaptation,
nullptr);
// Find Suspend Below Min Bitrate constraint.
FindConstraint(
constraints, MediaConstraints::kEnableVideoSuspendBelowMinBitrate,
&configuration->media_config.video.suspend_below_min_bitrate, nullptr);
ConstraintToOptional<int>(constraints,
MediaConstraints::kScreencastMinBitrate,
&configuration->screencast_min_bitrate);
}
void CopyConstraintsIntoAudioOptions(const MediaConstraints* constraints,
cricket::AudioOptions* options) {
if (!constraints) {
return;
}
ConstraintToOptional<bool>(constraints,
MediaConstraints::kGoogEchoCancellation,
&options->echo_cancellation);
ConstraintToOptional<bool>(constraints, MediaConstraints::kAutoGainControl,
&options->auto_gain_control);
ConstraintToOptional<bool>(constraints, MediaConstraints::kNoiseSuppression,
&options->noise_suppression);
ConstraintToOptional<bool>(constraints, MediaConstraints::kHighpassFilter,
&options->highpass_filter);
ConstraintToOptional<bool>(constraints, MediaConstraints::kAudioMirroring,
&options->stereo_swapping);
ConstraintToOptional<std::string>(
constraints, MediaConstraints::kAudioNetworkAdaptorConfig,
&options->audio_network_adaptor_config);
// When `kAudioNetworkAdaptorConfig` is defined, it both means that audio
// network adaptor is desired, and provides the config string.
if (options->audio_network_adaptor_config) {
options->audio_network_adaptor = true;
}
ConstraintToOptional<bool>(constraints,
MediaConstraints::kInitAudioRecordingOnSend,
&options->init_recording_on_send);
}
bool CopyConstraintsIntoOfferAnswerOptions(
const MediaConstraints* constraints,
PeerConnectionInterface::RTCOfferAnswerOptions* offer_answer_options) {
if (!constraints) {
return true;
}
bool value = false;
size_t mandatory_constraints_satisfied = 0;
if (FindConstraint(constraints, MediaConstraints::kOfferToReceiveAudio,
&value, &mandatory_constraints_satisfied)) {
offer_answer_options->offer_to_receive_audio =
value ? PeerConnectionInterface::RTCOfferAnswerOptions::
kOfferToReceiveMediaTrue
: 0;
}
if (FindConstraint(constraints, MediaConstraints::kOfferToReceiveVideo,
&value, &mandatory_constraints_satisfied)) {
offer_answer_options->offer_to_receive_video =
value ? PeerConnectionInterface::RTCOfferAnswerOptions::
kOfferToReceiveMediaTrue
: 0;
}
if (FindConstraint(constraints, MediaConstraints::kVoiceActivityDetection,
&value, &mandatory_constraints_satisfied)) {
offer_answer_options->voice_activity_detection = value;
}
if (FindConstraint(constraints, MediaConstraints::kUseRtpMux, &value,
&mandatory_constraints_satisfied)) {
offer_answer_options->use_rtp_mux = value;
}
if (FindConstraint(constraints, MediaConstraints::kIceRestart, &value,
&mandatory_constraints_satisfied)) {
offer_answer_options->ice_restart = value;
}
if (FindConstraint(constraints,
MediaConstraints::kRawPacketizationForVideoEnabled, &value,
&mandatory_constraints_satisfied)) {
offer_answer_options->raw_packetization_for_video = value;
}
int layers;
if (FindConstraint(constraints, MediaConstraints::kNumSimulcastLayers,
&layers, &mandatory_constraints_satisfied)) {
offer_answer_options->num_simulcast_layers = layers;
}
return mandatory_constraints_satisfied == constraints->GetMandatory().size();
}
} // namespace webrtc