diff options
Diffstat (limited to 'media/libaah_rtp/aah_tx_packet.cpp')
| -rw-r--r-- | media/libaah_rtp/aah_tx_packet.cpp | 331 |
1 files changed, 331 insertions, 0 deletions
diff --git a/media/libaah_rtp/aah_tx_packet.cpp b/media/libaah_rtp/aah_tx_packet.cpp new file mode 100644 index 0000000..3f6e0e9 --- /dev/null +++ b/media/libaah_rtp/aah_tx_packet.cpp @@ -0,0 +1,331 @@ +/* + * Copyright (C) 2011 The Android Open Source Project + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#define LOG_TAG "LibAAH_RTP" +#include <utils/Log.h> + +#include <arpa/inet.h> +#include <string.h> + +#include <media/stagefright/foundation/ADebug.h> + +#include "aah_tx_packet.h" + +namespace android { + +const int TRTPPacket::kRTPHeaderLen; +const uint32_t TRTPPacket::kTRTPEpochMask; + +TRTPPacket::~TRTPPacket() { + delete mPacket; +} + +/*** TRTP packet properties ***/ + +void TRTPPacket::setSeqNumber(uint16_t val) { + mSeqNumber = val; + + if (mIsPacked) { + const int kTRTPSeqNumberOffset = 2; + uint16_t* buf = reinterpret_cast<uint16_t*>( + mPacket + kTRTPSeqNumberOffset); + *buf = htons(mSeqNumber); + } +} + +uint16_t TRTPPacket::getSeqNumber() const { + return mSeqNumber; +} + +void TRTPPacket::setPTS(int64_t val) { + CHECK(!mIsPacked); + mPTS = val; + mPTSValid = true; +} + +int64_t TRTPPacket::getPTS() const { + return mPTS; +} + +void TRTPPacket::setEpoch(uint32_t val) { + mEpoch = val; + + if (mIsPacked) { + const int kTRTPEpochOffset = 8; + uint32_t* buf = reinterpret_cast<uint32_t*>( + mPacket + kTRTPEpochOffset); + uint32_t val = ntohl(*buf); + val &= ~(kTRTPEpochMask << kTRTPEpochShift); + val |= (mEpoch & kTRTPEpochMask) << kTRTPEpochShift; + *buf = htonl(val); + } +} + +void TRTPPacket::setProgramID(uint16_t val) { + CHECK(!mIsPacked); + mProgramID = val; +} + +void TRTPPacket::setSubstreamID(uint16_t val) { + CHECK(!mIsPacked); + mSubstreamID = val; +} + + +void TRTPPacket::setClockTransform(const LinearTransform& trans) { + CHECK(!mIsPacked); + mClockTranform = trans; + mClockTranformValid = true; +} + +uint8_t* TRTPPacket::getPacket() const { + CHECK(mIsPacked); + return mPacket; +} + +int TRTPPacket::getPacketLen() const { + CHECK(mIsPacked); + return mPacketLen; +} + +void TRTPPacket::setExpireTime(nsecs_t val) { + CHECK(!mIsPacked); + mExpireTime = val; +} + +nsecs_t TRTPPacket::getExpireTime() const { + return mExpireTime; +} + +/*** TRTP audio packet properties ***/ + +void TRTPAudioPacket::setCodecType(TRTPAudioCodecType val) { + CHECK(!mIsPacked); + mCodecType = val; +} + +void TRTPAudioPacket::setRandomAccessPoint(bool val) { + CHECK(!mIsPacked); + mRandomAccessPoint = val; +} + +void TRTPAudioPacket::setDropable(bool val) { + CHECK(!mIsPacked); + mDropable = val; +} + +void TRTPAudioPacket::setDiscontinuity(bool val) { + CHECK(!mIsPacked); + mDiscontinuity = val; +} + +void TRTPAudioPacket::setEndOfStream(bool val) { + CHECK(!mIsPacked); + mEndOfStream = val; +} + +void TRTPAudioPacket::setVolume(uint8_t val) { + CHECK(!mIsPacked); + mVolume = val; +} + +void TRTPAudioPacket::setAccessUnitData(void* data, int len) { + CHECK(!mIsPacked); + mAccessUnitData = data; + mAccessUnitLen = len; +} + +/*** TRTP control packet properties ***/ + +void TRTPControlPacket::setCommandID(TRTPCommandID val) { + CHECK(!mIsPacked); + mCommandID = val; +} + +/*** TRTP packet serializers ***/ + +void TRTPPacket::writeU8(uint8_t*& buf, uint8_t val) { + *buf = val; + buf++; +} + +void TRTPPacket::writeU16(uint8_t*& buf, uint16_t val) { + *reinterpret_cast<uint16_t*>(buf) = htons(val); + buf += 2; +} + +void TRTPPacket::writeU32(uint8_t*& buf, uint32_t val) { + *reinterpret_cast<uint32_t*>(buf) = htonl(val); + buf += 4; +} + +void TRTPPacket::writeU64(uint8_t*& buf, uint64_t val) { + buf[0] = static_cast<uint8_t>(val >> 56); + buf[1] = static_cast<uint8_t>(val >> 48); + buf[2] = static_cast<uint8_t>(val >> 40); + buf[3] = static_cast<uint8_t>(val >> 32); + buf[4] = static_cast<uint8_t>(val >> 24); + buf[5] = static_cast<uint8_t>(val >> 16); + buf[6] = static_cast<uint8_t>(val >> 8); + buf[7] = static_cast<uint8_t>(val); + buf += 8; +} + +void TRTPPacket::writeTRTPHeader(uint8_t*& buf, + bool isFirstFragment, + int totalPacketLen) { + // RTP header + writeU8(buf, + ((mVersion & 0x03) << 6) | + (static_cast<int>(mPadding) << 5) | + (static_cast<int>(mExtension) << 4) | + (mCsrcCount & 0x0F)); + writeU8(buf, + (static_cast<int>(isFirstFragment) << 7) | + (mPayloadType & 0x7F)); + writeU16(buf, mSeqNumber); + if (isFirstFragment && mPTSValid) { + writeU32(buf, mPTS & 0xFFFFFFFF); + } else { + writeU32(buf, 0); + } + writeU32(buf, + ((mEpoch & kTRTPEpochMask) << kTRTPEpochShift) | + ((mProgramID & 0x1F) << 5) | + (mSubstreamID & 0x1F)); + + // TRTP header + writeU8(buf, mTRTPVersion); + writeU8(buf, + ((mTRTPHeaderType & 0x0F) << 4) | + (mClockTranformValid ? 0x02 : 0x00) | + (mPTSValid ? 0x01 : 0x00)); + writeU32(buf, totalPacketLen - kRTPHeaderLen); + if (mPTSValid) { + writeU32(buf, mPTS >> 32); + } + + if (mClockTranformValid) { + writeU64(buf, mClockTranform.a_zero); + writeU32(buf, mClockTranform.a_to_b_numer); + writeU32(buf, mClockTranform.a_to_b_denom); + writeU64(buf, mClockTranform.b_zero); + } +} + +bool TRTPAudioPacket::pack() { + if (mIsPacked) { + return false; + } + + int packetLen = kRTPHeaderLen + + mAccessUnitLen + + TRTPHeaderLen(); + + // TODO : support multiple fragments + const int kMaxUDPPayloadLen = 65507; + if (packetLen > kMaxUDPPayloadLen) { + return false; + } + + mPacket = new uint8_t[packetLen]; + if (!mPacket) { + return false; + } + + mPacketLen = packetLen; + + uint8_t* cur = mPacket; + + writeTRTPHeader(cur, true, packetLen); + writeU8(cur, mCodecType); + writeU8(cur, + (static_cast<int>(mRandomAccessPoint) << 3) | + (static_cast<int>(mDropable) << 2) | + (static_cast<int>(mDiscontinuity) << 1) | + (static_cast<int>(mEndOfStream))); + writeU8(cur, mVolume); + + memcpy(cur, mAccessUnitData, mAccessUnitLen); + + mIsPacked = true; + return true; +} + +int TRTPPacket::TRTPHeaderLen() const { + // 6 bytes for version, payload type, flags and length. An additional 4 if + // there are upper timestamp bits present and another 24 if there is a clock + // transformation present. + return 6 + + (mClockTranformValid ? 24 : 0) + + (mPTSValid ? 4 : 0); +} + +int TRTPAudioPacket::TRTPHeaderLen() const { + // TRTPPacket::TRTPHeaderLen() for the base TRTPHeader. 3 bytes for audio's + // codec type, flags and volume field. Another 5 bytes if the codec type is + // PCM and we are sending sample rate/channel count. as well as however long + // the aux data (if present) is. + + int pcmParamLength; + switch(mCodecType) { + case kCodecPCMBigEndian: + case kCodecPCMLittleEndian: + pcmParamLength = 5; + break; + + default: + pcmParamLength = 0; + break; + } + + + // TODO : properly compute aux data length. Currently, nothing + // uses aux data, so its length is always 0. + int auxDataLength = 0; + return TRTPPacket::TRTPHeaderLen() + + 3 + + auxDataLength + + pcmParamLength; +} + +bool TRTPControlPacket::pack() { + if (mIsPacked) { + return false; + } + + // command packets contain a 2-byte command ID + int packetLen = kRTPHeaderLen + + TRTPHeaderLen() + + 2; + + mPacket = new uint8_t[packetLen]; + if (!mPacket) { + return false; + } + + mPacketLen = packetLen; + + uint8_t* cur = mPacket; + + writeTRTPHeader(cur, true, packetLen); + writeU16(cur, mCommandID); + + mIsPacked = true; + return true; +} + +} // namespace android |