| /* |
| * 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_NDEBUG 0 |
| #define LOG_TAG "AACWriter" |
| #include <utils/Log.h> |
| |
| #include <media/stagefright/AACWriter.h> |
| #include <media/stagefright/MediaBuffer.h> |
| #include <media/stagefright/foundation/ADebug.h> |
| #include <media/stagefright/MediaDefs.h> |
| #include <media/stagefright/MediaErrors.h> |
| #include <media/stagefright/MediaSource.h> |
| #include <media/stagefright/MetaData.h> |
| #include <media/mediarecorder.h> |
| #include <sys/prctl.h> |
| #include <fcntl.h> |
| |
| namespace android { |
| |
| AACWriter::AACWriter(const char *filename) |
| : mFd(-1), |
| mInitCheck(NO_INIT), |
| mStarted(false), |
| mPaused(false), |
| mResumed(false), |
| mChannelCount(-1), |
| mSampleRate(-1) { |
| |
| ALOGV("AACWriter Constructor"); |
| |
| mFd = open(filename, O_CREAT | O_LARGEFILE | O_TRUNC | O_RDWR); |
| if (mFd >= 0) { |
| mInitCheck = OK; |
| } |
| } |
| |
| AACWriter::AACWriter(int fd) |
| : mFd(dup(fd)), |
| mInitCheck(mFd < 0? NO_INIT: OK), |
| mStarted(false), |
| mPaused(false), |
| mResumed(false), |
| mChannelCount(-1), |
| mSampleRate(-1) { |
| } |
| |
| AACWriter::~AACWriter() { |
| if (mStarted) { |
| stop(); |
| } |
| |
| if (mFd != -1) { |
| close(mFd); |
| mFd = -1; |
| } |
| } |
| |
| status_t AACWriter::initCheck() const { |
| return mInitCheck; |
| } |
| |
| static int writeInt8(int fd, uint8_t x) { |
| return ::write(fd, &x, 1); |
| } |
| |
| |
| status_t AACWriter::addSource(const sp<MediaSource> &source) { |
| if (mInitCheck != OK) { |
| return mInitCheck; |
| } |
| |
| if (mSource != NULL) { |
| LOGE("AAC files only support a single track of audio."); |
| return UNKNOWN_ERROR; |
| } |
| |
| sp<MetaData> meta = source->getFormat(); |
| |
| const char *mime; |
| CHECK(meta->findCString(kKeyMIMEType, &mime)); |
| |
| CHECK(!strcasecmp(mime, MEDIA_MIMETYPE_AUDIO_AAC)); |
| CHECK(meta->findInt32(kKeyChannelCount, &mChannelCount)); |
| CHECK(meta->findInt32(kKeySampleRate, &mSampleRate)); |
| CHECK(mChannelCount >= 1 && mChannelCount <= 2); |
| |
| mSource = source; |
| return OK; |
| } |
| |
| status_t AACWriter::start(MetaData *params) { |
| if (mInitCheck != OK) { |
| return mInitCheck; |
| } |
| |
| if (mSource == NULL) { |
| return UNKNOWN_ERROR; |
| } |
| |
| if (mStarted && mPaused) { |
| mPaused = false; |
| mResumed = true; |
| return OK; |
| } else if (mStarted) { |
| // Already started, does nothing |
| return OK; |
| } |
| |
| mFrameDurationUs = (kSamplesPerFrame * 1000000LL + (mSampleRate >> 1)) |
| / mSampleRate; |
| |
| status_t err = mSource->start(); |
| |
| if (err != OK) { |
| return err; |
| } |
| |
| pthread_attr_t attr; |
| pthread_attr_init(&attr); |
| pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE); |
| |
| mReachedEOS = false; |
| mDone = false; |
| |
| pthread_create(&mThread, &attr, ThreadWrapper, this); |
| pthread_attr_destroy(&attr); |
| |
| mStarted = true; |
| |
| return OK; |
| } |
| |
| status_t AACWriter::pause() { |
| if (!mStarted) { |
| return OK; |
| } |
| mPaused = true; |
| return OK; |
| } |
| |
| status_t AACWriter::stop() { |
| if (!mStarted) { |
| return OK; |
| } |
| |
| mDone = true; |
| |
| void *dummy; |
| pthread_join(mThread, &dummy); |
| |
| status_t err = (status_t) dummy; |
| { |
| status_t status = mSource->stop(); |
| if (err == OK && |
| (status != OK && status != ERROR_END_OF_STREAM)) { |
| err = status; |
| } |
| } |
| |
| mStarted = false; |
| return err; |
| } |
| |
| bool AACWriter::exceedsFileSizeLimit() { |
| if (mMaxFileSizeLimitBytes == 0) { |
| return false; |
| } |
| return mEstimatedSizeBytes >= mMaxFileSizeLimitBytes; |
| } |
| |
| bool AACWriter::exceedsFileDurationLimit() { |
| if (mMaxFileDurationLimitUs == 0) { |
| return false; |
| } |
| return mEstimatedDurationUs >= mMaxFileDurationLimitUs; |
| } |
| |
| // static |
| void *AACWriter::ThreadWrapper(void *me) { |
| return (void *) static_cast<AACWriter *>(me)->threadFunc(); |
| } |
| |
| /* |
| * Returns an index into the sample rate table if the |
| * given sample rate is found; otherwise, returns -1. |
| */ |
| static bool getSampleRateTableIndex(int sampleRate, uint8_t* tableIndex) { |
| static const int kSampleRateTable[] = { |
| 96000, 88200, 64000, 48000, 44100, 32000, |
| 24000, 22050, 16000, 12000, 11025, 8000 |
| }; |
| const int tableSize = |
| sizeof(kSampleRateTable) / sizeof(kSampleRateTable[0]); |
| |
| *tableIndex = 0; |
| for (int index = 0; index < tableSize; ++index) { |
| if (sampleRate == kSampleRateTable[index]) { |
| ALOGV("Sample rate: %d and index: %d", |
| sampleRate, index); |
| *tableIndex = index; |
| return true; |
| } |
| } |
| |
| LOGE("Sampling rate %d bps is not supported", sampleRate); |
| return false; |
| } |
| |
| /* |
| * ADTS (Audio data transport stream) header structure. |
| * It consists of 7 or 9 bytes (with or without CRC): |
| * 12 bits of syncword 0xFFF, all bits must be 1 |
| * 1 bit of field ID. 0 for MPEG-4, and 1 for MPEG-2 |
| * 2 bits of MPEG layer. If in MPEG-TS, set to 0 |
| * 1 bit of protection absense. Set to 1 if no CRC. |
| * 2 bits of profile code. Set to 1 (The MPEG-4 Audio |
| * object type minus 1. We are using AAC-LC = 2) |
| * 4 bits of sampling frequency index code (15 is not allowed) |
| * 1 bit of private stream. Set to 0. |
| * 3 bits of channel configuration code. 0 resevered for inband PCM |
| * 1 bit of originality. Set to 0. |
| * 1 bit of home. Set to 0. |
| * 1 bit of copyrighted steam. Set to 0. |
| * 1 bit of copyright start. Set to 0. |
| * 13 bits of frame length. It included 7 ot 9 bytes header length. |
| * it is set to (protection absense? 7: 9) + size(AAC frame) |
| * 11 bits of buffer fullness. 0x7FF for VBR. |
| * 2 bits of frames count in one packet. Set to 0. |
| */ |
| status_t AACWriter::writeAdtsHeader(uint32_t frameLength) { |
| uint8_t data = 0xFF; |
| write(mFd, &data, 1); |
| |
| const uint8_t kFieldId = 0; |
| const uint8_t kMpegLayer = 0; |
| const uint8_t kProtectionAbsense = 1; // 1: kAdtsHeaderLength = 7 |
| data = 0xF0; |
| data |= (kFieldId << 3); |
| data |= (kMpegLayer << 1); |
| data |= kProtectionAbsense; |
| write(mFd, &data, 1); |
| |
| const uint8_t kProfileCode = 1; // AAC-LC |
| uint8_t kSampleFreqIndex; |
| CHECK(getSampleRateTableIndex(mSampleRate, &kSampleFreqIndex)); |
| const uint8_t kPrivateStream = 0; |
| const uint8_t kChannelConfigCode = mChannelCount; |
| data = (kProfileCode << 6); |
| data |= (kSampleFreqIndex << 2); |
| data |= (kPrivateStream << 1); |
| data |= (kChannelConfigCode >> 2); |
| write(mFd, &data, 1); |
| |
| // 4 bits from originality to copyright start |
| const uint8_t kCopyright = 0; |
| const uint32_t kFrameLength = frameLength; |
| data = ((kChannelConfigCode & 3) << 6); |
| data |= (kCopyright << 2); |
| data |= ((kFrameLength & 0x1800) >> 11); |
| write(mFd, &data, 1); |
| |
| data = ((kFrameLength & 0x07F8) >> 3); |
| write(mFd, &data, 1); |
| |
| const uint32_t kBufferFullness = 0x7FF; // VBR |
| data = ((kFrameLength & 0x07) << 5); |
| data |= ((kBufferFullness & 0x07C0) >> 6); |
| write(mFd, &data, 1); |
| |
| const uint8_t kFrameCount = 0; |
| data = ((kBufferFullness & 0x03F) << 2); |
| data |= kFrameCount; |
| write(mFd, &data, 1); |
| |
| return OK; |
| } |
| |
| status_t AACWriter::threadFunc() { |
| mEstimatedDurationUs = 0; |
| mEstimatedSizeBytes = 0; |
| int64_t previousPausedDurationUs = 0; |
| int64_t maxTimestampUs = 0; |
| status_t err = OK; |
| |
| prctl(PR_SET_NAME, (unsigned long)"AACWriterThread", 0, 0, 0); |
| |
| while (!mDone && err == OK) { |
| MediaBuffer *buffer; |
| err = mSource->read(&buffer); |
| |
| if (err != OK) { |
| break; |
| } |
| |
| if (mPaused) { |
| buffer->release(); |
| buffer = NULL; |
| continue; |
| } |
| |
| mEstimatedSizeBytes += kAdtsHeaderLength + buffer->range_length(); |
| if (exceedsFileSizeLimit()) { |
| buffer->release(); |
| buffer = NULL; |
| notify(MEDIA_RECORDER_EVENT_INFO, MEDIA_RECORDER_INFO_MAX_FILESIZE_REACHED, 0); |
| break; |
| } |
| |
| int32_t isCodecSpecific = 0; |
| if (buffer->meta_data()->findInt32(kKeyIsCodecConfig, &isCodecSpecific) && isCodecSpecific) { |
| ALOGV("Drop codec specific info buffer"); |
| buffer->release(); |
| buffer = NULL; |
| continue; |
| } |
| |
| int64_t timestampUs; |
| CHECK(buffer->meta_data()->findInt64(kKeyTime, ×tampUs)); |
| if (timestampUs > mEstimatedDurationUs) { |
| mEstimatedDurationUs = timestampUs; |
| } |
| if (mResumed) { |
| previousPausedDurationUs += (timestampUs - maxTimestampUs - mFrameDurationUs); |
| mResumed = false; |
| } |
| timestampUs -= previousPausedDurationUs; |
| ALOGV("time stamp: %lld, previous paused duration: %lld", |
| timestampUs, previousPausedDurationUs); |
| if (timestampUs > maxTimestampUs) { |
| maxTimestampUs = timestampUs; |
| } |
| |
| if (exceedsFileDurationLimit()) { |
| buffer->release(); |
| buffer = NULL; |
| notify(MEDIA_RECORDER_EVENT_INFO, MEDIA_RECORDER_INFO_MAX_DURATION_REACHED, 0); |
| break; |
| } |
| |
| // Each output AAC audio frame to the file contains |
| // 1. an ADTS header, followed by |
| // 2. the compressed audio data. |
| ssize_t dataLength = buffer->range_length(); |
| uint8_t *data = (uint8_t *)buffer->data() + buffer->range_offset(); |
| if (writeAdtsHeader(kAdtsHeaderLength + dataLength) != OK || |
| dataLength != write(mFd, data, dataLength)) { |
| err = ERROR_IO; |
| } |
| |
| buffer->release(); |
| buffer = NULL; |
| } |
| |
| close(mFd); |
| mFd = -1; |
| mReachedEOS = true; |
| if (err == ERROR_END_OF_STREAM) { |
| return OK; |
| } |
| return err; |
| } |
| |
| bool AACWriter::reachedEOS() { |
| return mReachedEOS; |
| } |
| |
| } // namespace android |