blob: 06695191b316069fa99af3f9789782cf1968849e [file] [log] [blame]
/*
* Copyright (c) 2012 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/rtp_rtcp/source/rtp_receiver_audio.h"
#include <assert.h> // assert
#include <math.h> // pow()
#include <string.h> // memcpy()
#include "common_types.h" // NOLINT(build/include)
#include "rtc_base/logging.h"
#include "rtc_base/trace_event.h"
namespace webrtc {
RTPReceiverStrategy* RTPReceiverStrategy::CreateAudioStrategy(
RtpData* data_callback) {
return new RTPReceiverAudio(data_callback);
}
RTPReceiverAudio::RTPReceiverAudio(RtpData* data_callback)
: RTPReceiverStrategy(data_callback),
TelephoneEventHandler(),
telephone_event_forward_to_decoder_(false),
telephone_event_payload_type_(-1),
cng_nb_payload_type_(-1),
cng_wb_payload_type_(-1),
cng_swb_payload_type_(-1),
cng_fb_payload_type_(-1),
num_energy_(0),
current_remote_energy_() {
memset(current_remote_energy_, 0, sizeof(current_remote_energy_));
}
RTPReceiverAudio::~RTPReceiverAudio() = default;
// Outband TelephoneEvent(DTMF) detection
void RTPReceiverAudio::SetTelephoneEventForwardToDecoder(
bool forward_to_decoder) {
rtc::CritScope lock(&crit_sect_);
telephone_event_forward_to_decoder_ = forward_to_decoder;
}
// Is forwarding of outband telephone events turned on/off?
bool RTPReceiverAudio::TelephoneEventForwardToDecoder() const {
rtc::CritScope lock(&crit_sect_);
return telephone_event_forward_to_decoder_;
}
bool RTPReceiverAudio::TelephoneEventPayloadType(
int8_t payload_type) const {
rtc::CritScope lock(&crit_sect_);
return telephone_event_payload_type_ == payload_type;
}
TelephoneEventHandler* RTPReceiverAudio::GetTelephoneEventHandler() {
return this;
}
bool RTPReceiverAudio::CNGPayloadType(int8_t payload_type) {
rtc::CritScope lock(&crit_sect_);
return payload_type == cng_nb_payload_type_ ||
payload_type == cng_wb_payload_type_ ||
payload_type == cng_swb_payload_type_ ||
payload_type == cng_fb_payload_type_;
}
// - Sample based or frame based codecs based on RFC 3551
// -
// - NOTE! There is one error in the RFC, stating G.722 uses 8 bits/samples.
// - The correct rate is 4 bits/sample.
// -
// - name of sampling default
// - encoding sample/frame bits/sample rate ms/frame ms/packet
// -
// - Sample based audio codecs
// - DVI4 sample 4 var. 20
// - G722 sample 4 16,000 20
// - G726-40 sample 5 8,000 20
// - G726-32 sample 4 8,000 20
// - G726-24 sample 3 8,000 20
// - G726-16 sample 2 8,000 20
// - L8 sample 8 var. 20
// - L16 sample 16 var. 20
// - PCMA sample 8 var. 20
// - PCMU sample 8 var. 20
// -
// - Frame based audio codecs
// - G723 frame N/A 8,000 30 30
// - G728 frame N/A 8,000 2.5 20
// - G729 frame N/A 8,000 10 20
// - G729D frame N/A 8,000 10 20
// - G729E frame N/A 8,000 10 20
// - GSM frame N/A 8,000 20 20
// - GSM-EFR frame N/A 8,000 20 20
// - LPC frame N/A 8,000 20 20
// - MPA frame N/A var. var.
// -
// - G7221 frame N/A
int32_t RTPReceiverAudio::OnNewPayloadTypeCreated(
int payload_type,
const SdpAudioFormat& audio_format) {
rtc::CritScope lock(&crit_sect_);
if (RtpUtility::StringCompare(audio_format.name.c_str(), "telephone-event",
15)) {
telephone_event_payload_type_ = payload_type;
}
if (RtpUtility::StringCompare(audio_format.name.c_str(), "cn", 2)) {
// We support comfort noise at four different frequencies.
if (audio_format.clockrate_hz == 8000) {
cng_nb_payload_type_ = payload_type;
} else if (audio_format.clockrate_hz == 16000) {
cng_wb_payload_type_ = payload_type;
} else if (audio_format.clockrate_hz == 32000) {
cng_swb_payload_type_ = payload_type;
} else if (audio_format.clockrate_hz == 48000) {
cng_fb_payload_type_ = payload_type;
} else {
assert(false);
return -1;
}
}
return 0;
}
int32_t RTPReceiverAudio::ParseRtpPacket(WebRtcRTPHeader* rtp_header,
const PayloadUnion& specific_payload,
const uint8_t* payload,
size_t payload_length,
int64_t timestamp_ms) {
rtp_header->type.Audio.numEnergy = rtp_header->header.numCSRCs;
num_energy_ = rtp_header->type.Audio.numEnergy;
if (rtp_header->type.Audio.numEnergy > 0 &&
rtp_header->type.Audio.numEnergy <= kRtpCsrcSize) {
memcpy(current_remote_energy_,
rtp_header->type.Audio.arrOfEnergy,
rtp_header->type.Audio.numEnergy);
}
if (first_packet_received_()) {
RTC_LOG(LS_INFO) << "Received first audio RTP packet";
}
return ParseAudioCodecSpecific(rtp_header, payload, payload_length,
specific_payload.audio_payload());
}
RTPAliveType RTPReceiverAudio::ProcessDeadOrAlive(
uint16_t last_payload_length) const {
// Our CNG is 9 bytes; if it's a likely CNG the receiver needs to check
// kRtpNoRtp against NetEq speech_type kOutputPLCtoCNG.
if (last_payload_length < 10) { // our CNG is 9 bytes
return kRtpNoRtp;
} else {
return kRtpDead;
}
}
void RTPReceiverAudio::CheckPayloadChanged(int8_t payload_type,
PayloadUnion* /* specific_payload */,
bool* should_discard_changes) {
*should_discard_changes =
TelephoneEventPayloadType(payload_type) || CNGPayloadType(payload_type);
}
int RTPReceiverAudio::Energy(uint8_t array_of_energy[kRtpCsrcSize]) const {
rtc::CritScope cs(&crit_sect_);
assert(num_energy_ <= kRtpCsrcSize);
if (num_energy_ > 0) {
memcpy(array_of_energy, current_remote_energy_,
sizeof(uint8_t) * num_energy_);
}
return num_energy_;
}
// We are not allowed to have any critsects when calling data_callback.
int32_t RTPReceiverAudio::ParseAudioCodecSpecific(
WebRtcRTPHeader* rtp_header,
const uint8_t* payload_data,
size_t payload_length,
const AudioPayload& audio_specific) {
RTC_DCHECK_GE(payload_length, rtp_header->header.paddingLength);
const size_t payload_data_length =
payload_length - rtp_header->header.paddingLength;
if (payload_data_length == 0) {
rtp_header->type.Audio.isCNG = false;
rtp_header->frameType = kEmptyFrame;
return data_callback_->OnReceivedPayloadData(nullptr, 0, rtp_header);
}
bool telephone_event_packet =
TelephoneEventPayloadType(rtp_header->header.payloadType);
if (telephone_event_packet) {
rtc::CritScope lock(&crit_sect_);
// RFC 4733 2.3
// 0 1 2 3
// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// | event |E|R| volume | duration |
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
//
if (payload_data_length % 4 != 0) {
return -1;
}
size_t number_of_events = payload_data_length / 4;
// sanity
if (number_of_events >= MAX_NUMBER_OF_PARALLEL_TELEPHONE_EVENTS) {
number_of_events = MAX_NUMBER_OF_PARALLEL_TELEPHONE_EVENTS;
}
for (size_t n = 0; n < number_of_events; ++n) {
RTC_DCHECK_GE(payload_data_length, (4 * n) + 2);
bool end = (payload_data[(4 * n) + 1] & 0x80) ? true : false;
std::set<uint8_t>::iterator event =
telephone_event_reported_.find(payload_data[4 * n]);
if (event != telephone_event_reported_.end()) {
// we have already seen this event
if (end) {
telephone_event_reported_.erase(payload_data[4 * n]);
}
} else {
if (end) {
// don't add if it's a end of a tone
} else {
telephone_event_reported_.insert(payload_data[4 * n]);
}
}
}
// RFC 4733 2.5.1.3 & 2.5.2.3 Long-Duration Events
// should not be a problem since we don't care about the duration
// RFC 4733 See 2.5.1.5. & 2.5.2.4. Multiple Events in a Packet
}
{
rtc::CritScope lock(&crit_sect_);
// Check if this is a CNG packet, receiver might want to know
if (CNGPayloadType(rtp_header->header.payloadType)) {
rtp_header->type.Audio.isCNG = true;
rtp_header->frameType = kAudioFrameCN;
} else {
rtp_header->frameType = kAudioFrameSpeech;
rtp_header->type.Audio.isCNG = false;
}
// check if it's a DTMF event, hence something we can playout
if (telephone_event_packet) {
if (!telephone_event_forward_to_decoder_) {
// don't forward event to decoder
return 0;
}
std::set<uint8_t>::iterator first =
telephone_event_reported_.begin();
if (first != telephone_event_reported_.end() && *first > 15) {
// don't forward non DTMF events
return 0;
}
}
}
rtp_header->type.Audio.channel = audio_specific.format.num_channels;
return data_callback_->OnReceivedPayloadData(payload_data,
payload_data_length, rtp_header);
}
} // namespace webrtc