diff options
Diffstat (limited to 'media/libstagefright/httplive/PlaylistFetcher.cpp')
| -rw-r--r-- | media/libstagefright/httplive/PlaylistFetcher.cpp | 976 |
1 files changed, 976 insertions, 0 deletions
diff --git a/media/libstagefright/httplive/PlaylistFetcher.cpp b/media/libstagefright/httplive/PlaylistFetcher.cpp new file mode 100644 index 0000000..973b779 --- /dev/null +++ b/media/libstagefright/httplive/PlaylistFetcher.cpp @@ -0,0 +1,976 @@ +/* + * Copyright (C) 2012 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_NDEBUG 0 +#define LOG_TAG "PlaylistFetcher" +#include <utils/Log.h> + +#include "PlaylistFetcher.h" + +#include "LiveDataSource.h" +#include "LiveSession.h" +#include "M3UParser.h" + +#include "include/avc_utils.h" +#include "include/HTTPBase.h" +#include "include/ID3.h" +#include "mpeg2ts/AnotherPacketSource.h" + +#include <media/IStreamSource.h> +#include <media/stagefright/foundation/ABitReader.h> +#include <media/stagefright/foundation/ABuffer.h> +#include <media/stagefright/foundation/ADebug.h> +#include <media/stagefright/foundation/hexdump.h> +#include <media/stagefright/FileSource.h> +#include <media/stagefright/MediaDefs.h> +#include <media/stagefright/MetaData.h> +#include <media/stagefright/Utils.h> + +#include <ctype.h> +#include <openssl/aes.h> +#include <openssl/md5.h> + +namespace android { + +// static +const int64_t PlaylistFetcher::kMinBufferedDurationUs = 10000000ll; + +PlaylistFetcher::PlaylistFetcher( + const sp<AMessage> ¬ify, + const sp<LiveSession> &session, + const char *uri) + : mNotify(notify), + mSession(session), + mURI(uri), + mStreamTypeMask(0), + mStartTimeUs(-1ll), + mLastPlaylistFetchTimeUs(-1ll), + mSeqNumber(-1), + mNumRetries(0), + mStartup(true), + mNextPTSTimeUs(-1ll), + mMonitorQueueGeneration(0), + mRefreshState(INITIAL_MINIMUM_RELOAD_DELAY), + mFirstPTSValid(false), + mAbsoluteTimeAnchorUs(0ll) { + memset(mPlaylistHash, 0, sizeof(mPlaylistHash)); +} + +PlaylistFetcher::~PlaylistFetcher() { +} + +int64_t PlaylistFetcher::getSegmentStartTimeUs(int32_t seqNumber) const { + CHECK(mPlaylist != NULL); + + int32_t firstSeqNumberInPlaylist; + if (mPlaylist->meta() == NULL || !mPlaylist->meta()->findInt32( + "media-sequence", &firstSeqNumberInPlaylist)) { + firstSeqNumberInPlaylist = 0; + } + + int32_t lastSeqNumberInPlaylist = + firstSeqNumberInPlaylist + (int32_t)mPlaylist->size() - 1; + + CHECK_GE(seqNumber, firstSeqNumberInPlaylist); + CHECK_LE(seqNumber, lastSeqNumberInPlaylist); + + int64_t segmentStartUs = 0ll; + for (int32_t index = 0; + index < seqNumber - firstSeqNumberInPlaylist; ++index) { + sp<AMessage> itemMeta; + CHECK(mPlaylist->itemAt( + index, NULL /* uri */, &itemMeta)); + + int64_t itemDurationUs; + CHECK(itemMeta->findInt64("durationUs", &itemDurationUs)); + + segmentStartUs += itemDurationUs; + } + + return segmentStartUs; +} + +bool PlaylistFetcher::timeToRefreshPlaylist(int64_t nowUs) const { + if (mPlaylist == NULL) { + CHECK_EQ((int)mRefreshState, (int)INITIAL_MINIMUM_RELOAD_DELAY); + return true; + } + + int32_t targetDurationSecs; + CHECK(mPlaylist->meta()->findInt32("target-duration", &targetDurationSecs)); + + int64_t targetDurationUs = targetDurationSecs * 1000000ll; + + int64_t minPlaylistAgeUs; + + switch (mRefreshState) { + case INITIAL_MINIMUM_RELOAD_DELAY: + { + size_t n = mPlaylist->size(); + if (n > 0) { + sp<AMessage> itemMeta; + CHECK(mPlaylist->itemAt(n - 1, NULL /* uri */, &itemMeta)); + + int64_t itemDurationUs; + CHECK(itemMeta->findInt64("durationUs", &itemDurationUs)); + + minPlaylistAgeUs = itemDurationUs; + break; + } + + // fall through + } + + case FIRST_UNCHANGED_RELOAD_ATTEMPT: + { + minPlaylistAgeUs = targetDurationUs / 2; + break; + } + + case SECOND_UNCHANGED_RELOAD_ATTEMPT: + { + minPlaylistAgeUs = (targetDurationUs * 3) / 2; + break; + } + + case THIRD_UNCHANGED_RELOAD_ATTEMPT: + { + minPlaylistAgeUs = targetDurationUs * 3; + break; + } + + default: + TRESPASS(); + break; + } + + return mLastPlaylistFetchTimeUs + minPlaylistAgeUs <= nowUs; +} + +status_t PlaylistFetcher::decryptBuffer( + size_t playlistIndex, const sp<ABuffer> &buffer) { + sp<AMessage> itemMeta; + bool found = false; + AString method; + + for (ssize_t i = playlistIndex; i >= 0; --i) { + AString uri; + CHECK(mPlaylist->itemAt(i, &uri, &itemMeta)); + + if (itemMeta->findString("cipher-method", &method)) { + found = true; + break; + } + } + + if (!found) { + method = "NONE"; + } + + if (method == "NONE") { + return OK; + } else if (!(method == "AES-128")) { + ALOGE("Unsupported cipher method '%s'", method.c_str()); + return ERROR_UNSUPPORTED; + } + + AString keyURI; + if (!itemMeta->findString("cipher-uri", &keyURI)) { + ALOGE("Missing key uri"); + return ERROR_MALFORMED; + } + + ssize_t index = mAESKeyForURI.indexOfKey(keyURI); + + sp<ABuffer> key; + if (index >= 0) { + key = mAESKeyForURI.valueAt(index); + } else { + status_t err = mSession->fetchFile(keyURI.c_str(), &key); + + if (err != OK) { + ALOGE("failed to fetch cipher key from '%s'.", keyURI.c_str()); + return ERROR_IO; + } else if (key->size() != 16) { + ALOGE("key file '%s' wasn't 16 bytes in size.", keyURI.c_str()); + return ERROR_MALFORMED; + } + + mAESKeyForURI.add(keyURI, key); + } + + AES_KEY aes_key; + if (AES_set_decrypt_key(key->data(), 128, &aes_key) != 0) { + ALOGE("failed to set AES decryption key."); + return UNKNOWN_ERROR; + } + + unsigned char aes_ivec[16]; + + AString iv; + if (itemMeta->findString("cipher-iv", &iv)) { + if ((!iv.startsWith("0x") && !iv.startsWith("0X")) + || iv.size() != 16 * 2 + 2) { + ALOGE("malformed cipher IV '%s'.", iv.c_str()); + return ERROR_MALFORMED; + } + + memset(aes_ivec, 0, sizeof(aes_ivec)); + for (size_t i = 0; i < 16; ++i) { + char c1 = tolower(iv.c_str()[2 + 2 * i]); + char c2 = tolower(iv.c_str()[3 + 2 * i]); + if (!isxdigit(c1) || !isxdigit(c2)) { + ALOGE("malformed cipher IV '%s'.", iv.c_str()); + return ERROR_MALFORMED; + } + uint8_t nibble1 = isdigit(c1) ? c1 - '0' : c1 - 'a' + 10; + uint8_t nibble2 = isdigit(c2) ? c2 - '0' : c2 - 'a' + 10; + + aes_ivec[i] = nibble1 << 4 | nibble2; + } + } else { + memset(aes_ivec, 0, sizeof(aes_ivec)); + aes_ivec[15] = mSeqNumber & 0xff; + aes_ivec[14] = (mSeqNumber >> 8) & 0xff; + aes_ivec[13] = (mSeqNumber >> 16) & 0xff; + aes_ivec[12] = (mSeqNumber >> 24) & 0xff; + } + + AES_cbc_encrypt( + buffer->data(), buffer->data(), buffer->size(), + &aes_key, aes_ivec, AES_DECRYPT); + + // hexdump(buffer->data(), buffer->size()); + + size_t n = buffer->size(); + CHECK_GT(n, 0u); + + size_t pad = buffer->data()[n - 1]; + + CHECK_GT(pad, 0u); + CHECK_LE(pad, 16u); + CHECK_GE((size_t)n, pad); + for (size_t i = 0; i < pad; ++i) { + CHECK_EQ((unsigned)buffer->data()[n - 1 - i], pad); + } + + n -= pad; + + buffer->setRange(buffer->offset(), n); + + return OK; +} + +void PlaylistFetcher::postMonitorQueue(int64_t delayUs) { + sp<AMessage> msg = new AMessage(kWhatMonitorQueue, id()); + msg->setInt32("generation", mMonitorQueueGeneration); + msg->post(delayUs); +} + +void PlaylistFetcher::cancelMonitorQueue() { + ++mMonitorQueueGeneration; +} + +void PlaylistFetcher::startAsync( + const sp<AnotherPacketSource> &audioSource, + const sp<AnotherPacketSource> &videoSource, + const sp<AnotherPacketSource> &subtitleSource, + int64_t startTimeUs) { + sp<AMessage> msg = new AMessage(kWhatStart, id()); + + uint32_t streamTypeMask = 0ul; + + if (audioSource != NULL) { + msg->setPointer("audioSource", audioSource.get()); + streamTypeMask |= LiveSession::STREAMTYPE_AUDIO; + } + + if (videoSource != NULL) { + msg->setPointer("videoSource", videoSource.get()); + streamTypeMask |= LiveSession::STREAMTYPE_VIDEO; + } + + if (subtitleSource != NULL) { + msg->setPointer("subtitleSource", subtitleSource.get()); + streamTypeMask |= LiveSession::STREAMTYPE_SUBTITLES; + } + + msg->setInt32("streamTypeMask", streamTypeMask); + msg->setInt64("startTimeUs", startTimeUs); + msg->post(); +} + +void PlaylistFetcher::pauseAsync() { + (new AMessage(kWhatPause, id()))->post(); +} + +void PlaylistFetcher::stopAsync() { + (new AMessage(kWhatStop, id()))->post(); +} + +void PlaylistFetcher::onMessageReceived(const sp<AMessage> &msg) { + switch (msg->what()) { + case kWhatStart: + { + status_t err = onStart(msg); + + sp<AMessage> notify = mNotify->dup(); + notify->setInt32("what", kWhatStarted); + notify->setInt32("err", err); + notify->post(); + break; + } + + case kWhatPause: + { + onPause(); + + sp<AMessage> notify = mNotify->dup(); + notify->setInt32("what", kWhatPaused); + notify->post(); + break; + } + + case kWhatStop: + { + onStop(); + + sp<AMessage> notify = mNotify->dup(); + notify->setInt32("what", kWhatStopped); + notify->post(); + break; + } + + case kWhatMonitorQueue: + { + int32_t generation; + CHECK(msg->findInt32("generation", &generation)); + + if (generation != mMonitorQueueGeneration) { + // Stale event + break; + } + + onMonitorQueue(); + break; + } + + default: + TRESPASS(); + } +} + +status_t PlaylistFetcher::onStart(const sp<AMessage> &msg) { + mPacketSources.clear(); + + uint32_t streamTypeMask; + CHECK(msg->findInt32("streamTypeMask", (int32_t *)&streamTypeMask)); + + int64_t startTimeUs; + CHECK(msg->findInt64("startTimeUs", &startTimeUs)); + + if (streamTypeMask & LiveSession::STREAMTYPE_AUDIO) { + void *ptr; + CHECK(msg->findPointer("audioSource", &ptr)); + + mPacketSources.add( + LiveSession::STREAMTYPE_AUDIO, + static_cast<AnotherPacketSource *>(ptr)); + } + + if (streamTypeMask & LiveSession::STREAMTYPE_VIDEO) { + void *ptr; + CHECK(msg->findPointer("videoSource", &ptr)); + + mPacketSources.add( + LiveSession::STREAMTYPE_VIDEO, + static_cast<AnotherPacketSource *>(ptr)); + } + + if (streamTypeMask & LiveSession::STREAMTYPE_SUBTITLES) { + void *ptr; + CHECK(msg->findPointer("subtitleSource", &ptr)); + + mPacketSources.add( + LiveSession::STREAMTYPE_SUBTITLES, + static_cast<AnotherPacketSource *>(ptr)); + } + + mStreamTypeMask = streamTypeMask; + mStartTimeUs = startTimeUs; + + if (mStartTimeUs >= 0ll) { + mSeqNumber = -1; + mStartup = true; + } + + postMonitorQueue(); + + return OK; +} + +void PlaylistFetcher::onPause() { + cancelMonitorQueue(); + + mPacketSources.clear(); + mStreamTypeMask = 0; +} + +void PlaylistFetcher::onStop() { + cancelMonitorQueue(); + + for (size_t i = 0; i < mPacketSources.size(); ++i) { + mPacketSources.valueAt(i)->clear(); + } + + mPacketSources.clear(); + mStreamTypeMask = 0; +} + +void PlaylistFetcher::notifyError(status_t err) { + sp<AMessage> notify = mNotify->dup(); + notify->setInt32("what", kWhatError); + notify->setInt32("err", err); + notify->post(); +} + +void PlaylistFetcher::queueDiscontinuity( + ATSParser::DiscontinuityType type, const sp<AMessage> &extra) { + for (size_t i = 0; i < mPacketSources.size(); ++i) { + mPacketSources.valueAt(i)->queueDiscontinuity(type, extra); + } +} + +void PlaylistFetcher::onMonitorQueue() { + bool downloadMore = false; + + status_t finalResult; + if (mStreamTypeMask == LiveSession::STREAMTYPE_SUBTITLES) { + sp<AnotherPacketSource> packetSource = + mPacketSources.valueFor(LiveSession::STREAMTYPE_SUBTITLES); + + int64_t bufferedDurationUs = + packetSource->getBufferedDurationUs(&finalResult); + + downloadMore = (bufferedDurationUs < kMinBufferedDurationUs); + finalResult = OK; + } else { + bool first = true; + int64_t minBufferedDurationUs = 0ll; + + for (size_t i = 0; i < mPacketSources.size(); ++i) { + if ((mStreamTypeMask & mPacketSources.keyAt(i)) == 0) { + continue; + } + + int64_t bufferedDurationUs = + mPacketSources.valueAt(i)->getBufferedDurationUs(&finalResult); + + if (first || bufferedDurationUs < minBufferedDurationUs) { + minBufferedDurationUs = bufferedDurationUs; + first = false; + } + } + + downloadMore = + !first && (minBufferedDurationUs < kMinBufferedDurationUs); + } + + if (finalResult == OK && downloadMore) { + onDownloadNext(); + } else { + // Nothing to do yet, try again in a second. + + sp<AMessage> msg = mNotify->dup(); + msg->setInt32("what", kWhatTemporarilyDoneFetching); + msg->post(); + + postMonitorQueue(1000000ll); + } +} + +void PlaylistFetcher::onDownloadNext() { + int64_t nowUs = ALooper::GetNowUs(); + + if (mLastPlaylistFetchTimeUs < 0ll + || (!mPlaylist->isComplete() && timeToRefreshPlaylist(nowUs))) { + bool unchanged; + sp<M3UParser> playlist = mSession->fetchPlaylist( + mURI.c_str(), mPlaylistHash, &unchanged); + + if (playlist == NULL) { + if (unchanged) { + // We succeeded in fetching the playlist, but it was + // unchanged from the last time we tried. + + if (mRefreshState != THIRD_UNCHANGED_RELOAD_ATTEMPT) { + mRefreshState = (RefreshState)(mRefreshState + 1); + } + } else { + ALOGE("failed to load playlist at url '%s'", mURI.c_str()); + notifyError(ERROR_IO); + return; + } + } else { + mRefreshState = INITIAL_MINIMUM_RELOAD_DELAY; + mPlaylist = playlist; + + if (mPlaylist->isComplete() || mPlaylist->isEvent()) { + updateDuration(); + } + } + + mLastPlaylistFetchTimeUs = ALooper::GetNowUs(); + } + + int32_t firstSeqNumberInPlaylist; + if (mPlaylist->meta() == NULL || !mPlaylist->meta()->findInt32( + "media-sequence", &firstSeqNumberInPlaylist)) { + firstSeqNumberInPlaylist = 0; + } + + bool seekDiscontinuity = false; + bool explicitDiscontinuity = false; + + const int32_t lastSeqNumberInPlaylist = + firstSeqNumberInPlaylist + (int32_t)mPlaylist->size() - 1; + + if (mSeqNumber < 0) { + CHECK_GE(mStartTimeUs, 0ll); + + if (mPlaylist->isComplete() || mPlaylist->isEvent()) { + mSeqNumber = getSeqNumberForTime(mStartTimeUs); + } else { + // If this is a live session, start 3 segments from the end. + mSeqNumber = lastSeqNumberInPlaylist - 3; + if (mSeqNumber < firstSeqNumberInPlaylist) { + mSeqNumber = firstSeqNumberInPlaylist; + } + } + + mStartTimeUs = -1ll; + } + + if (mSeqNumber < firstSeqNumberInPlaylist + || mSeqNumber > lastSeqNumberInPlaylist) { + if (!mPlaylist->isComplete() && mNumRetries < kMaxNumRetries) { + ++mNumRetries; + + if (mSeqNumber > lastSeqNumberInPlaylist) { + mLastPlaylistFetchTimeUs = -1; + postMonitorQueue(3000000ll); + return; + } + + // we've missed the boat, let's start from the lowest sequence + // number available and signal a discontinuity. + + ALOGI("We've missed the boat, restarting playback."); + mSeqNumber = lastSeqNumberInPlaylist; + explicitDiscontinuity = true; + + // fall through + } else { + ALOGE("Cannot find sequence number %d in playlist " + "(contains %d - %d)", + mSeqNumber, firstSeqNumberInPlaylist, + firstSeqNumberInPlaylist + mPlaylist->size() - 1); + + notifyError(ERROR_END_OF_STREAM); + return; + } + } + + mNumRetries = 0; + + AString uri; + sp<AMessage> itemMeta; + CHECK(mPlaylist->itemAt( + mSeqNumber - firstSeqNumberInPlaylist, + &uri, + &itemMeta)); + + int32_t val; + if (itemMeta->findInt32("discontinuity", &val) && val != 0) { + explicitDiscontinuity = true; + } + + int64_t range_offset, range_length; + if (!itemMeta->findInt64("range-offset", &range_offset) + || !itemMeta->findInt64("range-length", &range_length)) { + range_offset = 0; + range_length = -1; + } + + ALOGV("fetching segment %d from (%d .. %d)", + mSeqNumber, firstSeqNumberInPlaylist, lastSeqNumberInPlaylist); + + ALOGV("fetching '%s'", uri.c_str()); + + sp<ABuffer> buffer; + status_t err = mSession->fetchFile( + uri.c_str(), &buffer, range_offset, range_length); + + if (err != OK) { + ALOGE("failed to fetch .ts segment at url '%s'", uri.c_str()); + notifyError(err); + return; + } + + CHECK(buffer != NULL); + + err = decryptBuffer(mSeqNumber - firstSeqNumberInPlaylist, buffer); + + if (err != OK) { + ALOGE("decryptBuffer failed w/ error %d", err); + + notifyError(err); + return; + } + + if (mStartup || seekDiscontinuity || explicitDiscontinuity) { + // Signal discontinuity. + + if (mPlaylist->isComplete() || mPlaylist->isEvent()) { + // If this was a live event this made no sense since + // we don't have access to all the segment before the current + // one. + mNextPTSTimeUs = getSegmentStartTimeUs(mSeqNumber); + } + + if (seekDiscontinuity || explicitDiscontinuity) { + ALOGI("queueing discontinuity (seek=%d, explicit=%d)", + seekDiscontinuity, explicitDiscontinuity); + + queueDiscontinuity( + explicitDiscontinuity + ? ATSParser::DISCONTINUITY_FORMATCHANGE + : ATSParser::DISCONTINUITY_SEEK, + NULL /* extra */); + } + } + + err = extractAndQueueAccessUnits(buffer, itemMeta); + + if (err != OK) { + notifyError(err); + return; + } + + ++mSeqNumber; + + postMonitorQueue(); + + mStartup = false; +} + +int32_t PlaylistFetcher::getSeqNumberForTime(int64_t timeUs) const { + int32_t firstSeqNumberInPlaylist; + if (mPlaylist->meta() == NULL || !mPlaylist->meta()->findInt32( + "media-sequence", &firstSeqNumberInPlaylist)) { + firstSeqNumberInPlaylist = 0; + } + + size_t index = 0; + int64_t segmentStartUs = 0; + while (index < mPlaylist->size()) { + sp<AMessage> itemMeta; + CHECK(mPlaylist->itemAt( + index, NULL /* uri */, &itemMeta)); + + int64_t itemDurationUs; + CHECK(itemMeta->findInt64("durationUs", &itemDurationUs)); + + if (timeUs < segmentStartUs + itemDurationUs) { + break; + } + + segmentStartUs += itemDurationUs; + ++index; + } + + if (index >= mPlaylist->size()) { + index = mPlaylist->size() - 1; + } + + return firstSeqNumberInPlaylist + index; +} + +status_t PlaylistFetcher::extractAndQueueAccessUnits( + const sp<ABuffer> &buffer, const sp<AMessage> &itemMeta) { + if (buffer->size() > 0 && buffer->data()[0] == 0x47) { + // Let's assume this is an MPEG2 transport stream. + + if ((buffer->size() % 188) != 0) { + ALOGE("MPEG2 transport stream is not an even multiple of 188 " + "bytes in length."); + return ERROR_MALFORMED; + } + + if (mTSParser == NULL) { + mTSParser = new ATSParser; + } + + if (mNextPTSTimeUs >= 0ll) { + sp<AMessage> extra = new AMessage; + extra->setInt64(IStreamListener::kKeyMediaTimeUs, mNextPTSTimeUs); + + mTSParser->signalDiscontinuity( + ATSParser::DISCONTINUITY_SEEK, extra); + + mNextPTSTimeUs = -1ll; + } + + size_t offset = 0; + while (offset < buffer->size()) { + status_t err = mTSParser->feedTSPacket(buffer->data() + offset, 188); + + if (err != OK) { + return err; + } + + offset += 188; + } + + for (size_t i = mPacketSources.size(); i-- > 0;) { + sp<AnotherPacketSource> packetSource = mPacketSources.valueAt(i); + + ATSParser::SourceType type; + switch (mPacketSources.keyAt(i)) { + case LiveSession::STREAMTYPE_VIDEO: + type = ATSParser::VIDEO; + break; + + case LiveSession::STREAMTYPE_AUDIO: + type = ATSParser::AUDIO; + break; + + case LiveSession::STREAMTYPE_SUBTITLES: + { + ALOGE("MPEG2 Transport streams do not contain subtitles."); + return ERROR_MALFORMED; + break; + } + + default: + TRESPASS(); + } + + sp<AnotherPacketSource> source = + static_cast<AnotherPacketSource *>( + mTSParser->getSource(type).get()); + + if (source == NULL) { + ALOGW("MPEG2 Transport stream does not contain %s data.", + type == ATSParser::VIDEO ? "video" : "audio"); + + mStreamTypeMask &= ~mPacketSources.keyAt(i); + mPacketSources.removeItemsAt(i); + continue; + } + + sp<ABuffer> accessUnit; + status_t finalResult; + while (source->hasBufferAvailable(&finalResult) + && source->dequeueAccessUnit(&accessUnit) == OK) { + // Note that we do NOT dequeue any discontinuities. + + packetSource->queueAccessUnit(accessUnit); + } + + if (packetSource->getFormat() == NULL) { + packetSource->setFormat(source->getFormat()); + } + } + + return OK; + } else if (buffer->size() >= 7 && !memcmp("WEBVTT\n", buffer->data(), 7)) { + if (mStreamTypeMask != LiveSession::STREAMTYPE_SUBTITLES) { + ALOGE("This stream only contains subtitles."); + return ERROR_MALFORMED; + } + + const sp<AnotherPacketSource> packetSource = + mPacketSources.valueFor(LiveSession::STREAMTYPE_SUBTITLES); + + int64_t durationUs; + CHECK(itemMeta->findInt64("durationUs", &durationUs)); + buffer->meta()->setInt64("timeUs", getSegmentStartTimeUs(mSeqNumber)); + buffer->meta()->setInt64("durationUs", durationUs); + + packetSource->queueAccessUnit(buffer); + return OK; + } + + if (mNextPTSTimeUs >= 0ll) { + mFirstPTSValid = false; + mAbsoluteTimeAnchorUs = mNextPTSTimeUs; + mNextPTSTimeUs = -1ll; + } + + // This better be an ISO 13818-7 (AAC) or ISO 13818-1 (MPEG) audio + // stream prefixed by an ID3 tag. + + bool firstID3Tag = true; + uint64_t PTS = 0; + + for (;;) { + // Make sure to skip all ID3 tags preceding the audio data. + // At least one must be present to provide the PTS timestamp. + + ID3 id3(buffer->data(), buffer->size(), true /* ignoreV1 */); + if (!id3.isValid()) { + if (firstID3Tag) { + ALOGE("Unable to parse ID3 tag."); + return ERROR_MALFORMED; + } else { + break; + } + } + + if (firstID3Tag) { + bool found = false; + + ID3::Iterator it(id3, "PRIV"); + while (!it.done()) { + size_t length; + const uint8_t *data = it.getData(&length); + + static const char *kMatchName = + "com.apple.streaming.transportStreamTimestamp"; + static const size_t kMatchNameLen = strlen(kMatchName); + + if (length == kMatchNameLen + 1 + 8 + && !strncmp((const char *)data, kMatchName, kMatchNameLen)) { + found = true; + PTS = U64_AT(&data[kMatchNameLen + 1]); + } + + it.next(); + } + + if (!found) { + ALOGE("Unable to extract transportStreamTimestamp from ID3 tag."); + return ERROR_MALFORMED; + } + } + + // skip the ID3 tag + buffer->setRange( + buffer->offset() + id3.rawSize(), buffer->size() - id3.rawSize()); + + firstID3Tag = false; + } + + if (!mFirstPTSValid) { + mFirstPTSValid = true; + mFirstPTS = PTS; + } + PTS -= mFirstPTS; + + int64_t timeUs = (PTS * 100ll) / 9ll + mAbsoluteTimeAnchorUs; + + if (mStreamTypeMask != LiveSession::STREAMTYPE_AUDIO) { + ALOGW("This stream only contains audio data!"); + + mStreamTypeMask &= LiveSession::STREAMTYPE_AUDIO; + + if (mStreamTypeMask == 0) { + return OK; + } + } + + sp<AnotherPacketSource> packetSource = + mPacketSources.valueFor(LiveSession::STREAMTYPE_AUDIO); + + if (packetSource->getFormat() == NULL && buffer->size() >= 7) { + ABitReader bits(buffer->data(), buffer->size()); + + // adts_fixed_header + + CHECK_EQ(bits.getBits(12), 0xfffu); + bits.skipBits(3); // ID, layer + bool protection_absent = bits.getBits(1) != 0; + + unsigned profile = bits.getBits(2); + CHECK_NE(profile, 3u); + unsigned sampling_freq_index = bits.getBits(4); + bits.getBits(1); // private_bit + unsigned channel_configuration = bits.getBits(3); + CHECK_NE(channel_configuration, 0u); + bits.skipBits(2); // original_copy, home + + sp<MetaData> meta = MakeAACCodecSpecificData( + profile, sampling_freq_index, channel_configuration); + + meta->setInt32(kKeyIsADTS, true); + + packetSource->setFormat(meta); + } + + int64_t numSamples = 0ll; + int32_t sampleRate; + CHECK(packetSource->getFormat()->findInt32(kKeySampleRate, &sampleRate)); + + size_t offset = 0; + while (offset < buffer->size()) { + const uint8_t *adtsHeader = buffer->data() + offset; + CHECK_LT(offset + 5, buffer->size()); + + unsigned aac_frame_length = + ((adtsHeader[3] & 3) << 11) + | (adtsHeader[4] << 3) + | (adtsHeader[5] >> 5); + + CHECK_LE(offset + aac_frame_length, buffer->size()); + + sp<ABuffer> unit = new ABuffer(aac_frame_length); + memcpy(unit->data(), adtsHeader, aac_frame_length); + + int64_t unitTimeUs = timeUs + numSamples * 1000000ll / sampleRate; + unit->meta()->setInt64("timeUs", unitTimeUs); + + // Each AAC frame encodes 1024 samples. + numSamples += 1024; + + packetSource->queueAccessUnit(unit); + + offset += aac_frame_length; + } + + return OK; +} + +void PlaylistFetcher::updateDuration() { + int64_t durationUs = 0ll; + for (size_t index = 0; index < mPlaylist->size(); ++index) { + sp<AMessage> itemMeta; + CHECK(mPlaylist->itemAt( + index, NULL /* uri */, &itemMeta)); + + int64_t itemDurationUs; + CHECK(itemMeta->findInt64("durationUs", &itemDurationUs)); + + durationUs += itemDurationUs; + } + + sp<AMessage> msg = mNotify->dup(); + msg->setInt32("what", kWhatDurationUpdate); + msg->setInt64("durationUs", durationUs); + msg->post(); +} + +} // namespace android |