blob: 03dcbf90ff43c12463d6f6c16467c336f49acd4c [file] [log] [blame]
/*
* Copyright (C) 2009 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 "AMRExtractor"
#include <utils/Log.h>
#include "include/AMRExtractor.h"
#include <media/stagefright/foundation/ADebug.h>
#include <media/stagefright/DataSource.h>
#include <media/stagefright/MediaBufferGroup.h>
#include <media/stagefright/MediaDefs.h>
#include <media/stagefright/MediaErrors.h>
#include <media/stagefright/MediaSource.h>
#include <media/stagefright/MetaData.h>
#include <utils/String8.h>
namespace android {
class AMRSource : public MediaSource {
public:
AMRSource(const sp<DataSource> &source,
const sp<MetaData> &meta,
bool isWide,
const off64_t *offset_table,
size_t offset_table_length);
virtual status_t start(MetaData *params = NULL);
virtual status_t stop();
virtual sp<MetaData> getFormat();
virtual status_t read(
MediaBuffer **buffer, const ReadOptions *options = NULL);
protected:
virtual ~AMRSource();
private:
sp<DataSource> mDataSource;
sp<MetaData> mMeta;
bool mIsWide;
off64_t mOffset;
int64_t mCurrentTimeUs;
bool mStarted;
MediaBufferGroup *mGroup;
off64_t mOffsetTable[OFFSET_TABLE_LEN];
size_t mOffsetTableLength;
AMRSource(const AMRSource &);
AMRSource &operator=(const AMRSource &);
};
////////////////////////////////////////////////////////////////////////////////
static size_t getFrameSize(bool isWide, unsigned FT) {
static const size_t kFrameSizeNB[16] = {
95, 103, 118, 134, 148, 159, 204, 244,
39, 43, 38, 37, // SID
0, 0, 0, // future use
0 // no data
};
static const size_t kFrameSizeWB[16] = {
132, 177, 253, 285, 317, 365, 397, 461, 477,
40, // SID
0, 0, 0, 0, // future use
0, // speech lost
0 // no data
};
if (FT > 15 || (isWide && FT > 9 && FT < 14) || (!isWide && FT > 11 && FT < 15)) {
ALOGE("illegal AMR frame type %d", FT);
return 0;
}
size_t frameSize = isWide ? kFrameSizeWB[FT] : kFrameSizeNB[FT];
// Round up bits to bytes and add 1 for the header byte.
frameSize = (frameSize + 7) / 8 + 1;
return frameSize;
}
static status_t getFrameSizeByOffset(const sp<DataSource> &source,
off64_t offset, bool isWide, size_t *frameSize) {
uint8_t header;
if (source->readAt(offset, &header, 1) < 1) {
return ERROR_IO;
}
unsigned FT = (header >> 3) & 0x0f;
*frameSize = getFrameSize(isWide, FT);
if (*frameSize == 0) {
return ERROR_MALFORMED;
}
return OK;
}
AMRExtractor::AMRExtractor(const sp<DataSource> &source)
: mDataSource(source),
mInitCheck(NO_INIT),
mOffsetTableLength(0) {
String8 mimeType;
float confidence;
if (!SniffAMR(mDataSource, &mimeType, &confidence, NULL)) {
return;
}
mIsWide = (mimeType == MEDIA_MIMETYPE_AUDIO_AMR_WB);
mMeta = new MetaData;
mMeta->setCString(
kKeyMIMEType, mIsWide ? MEDIA_MIMETYPE_AUDIO_AMR_WB
: MEDIA_MIMETYPE_AUDIO_AMR_NB);
mMeta->setInt32(kKeyChannelCount, 1);
mMeta->setInt32(kKeySampleRate, mIsWide ? 16000 : 8000);
off64_t offset = mIsWide ? 9 : 6;
off64_t streamSize;
size_t frameSize, numFrames = 0;
int64_t duration = 0;
if (mDataSource->getSize(&streamSize) == OK) {
while (offset < streamSize) {
if (getFrameSizeByOffset(source, offset, mIsWide, &frameSize) != OK) {
return;
}
if ((numFrames % 50 == 0) && (numFrames / 50 < OFFSET_TABLE_LEN)) {
CHECK_EQ(mOffsetTableLength, numFrames / 50);
mOffsetTable[mOffsetTableLength] = offset - (mIsWide ? 9: 6);
mOffsetTableLength ++;
}
offset += frameSize;
duration += 20000; // Each frame is 20ms
numFrames ++;
}
mMeta->setInt64(kKeyDuration, duration);
}
mInitCheck = OK;
}
AMRExtractor::~AMRExtractor() {
}
sp<MetaData> AMRExtractor::getMetaData() {
sp<MetaData> meta = new MetaData;
if (mInitCheck != OK) {
return meta;
}
meta->setCString(kKeyMIMEType, mIsWide ? "audio/amr-wb" : "audio/amr");
return meta;
}
size_t AMRExtractor::countTracks() {
return mInitCheck == OK ? 1 : 0;
}
sp<MediaSource> AMRExtractor::getTrack(size_t index) {
if (mInitCheck != OK || index != 0) {
return NULL;
}
return new AMRSource(mDataSource, mMeta, mIsWide,
mOffsetTable, mOffsetTableLength);
}
sp<MetaData> AMRExtractor::getTrackMetaData(size_t index, uint32_t flags) {
if (mInitCheck != OK || index != 0) {
return NULL;
}
return mMeta;
}
////////////////////////////////////////////////////////////////////////////////
AMRSource::AMRSource(
const sp<DataSource> &source, const sp<MetaData> &meta,
bool isWide, const off64_t *offset_table, size_t offset_table_length)
: mDataSource(source),
mMeta(meta),
mIsWide(isWide),
mOffset(mIsWide ? 9 : 6),
mCurrentTimeUs(0),
mStarted(false),
mGroup(NULL),
mOffsetTableLength(offset_table_length) {
if (mOffsetTableLength > 0 && mOffsetTableLength <= OFFSET_TABLE_LEN) {
memcpy ((char*)mOffsetTable, (char*)offset_table, sizeof(off64_t) * mOffsetTableLength);
}
}
AMRSource::~AMRSource() {
if (mStarted) {
stop();
}
}
status_t AMRSource::start(MetaData *params) {
CHECK(!mStarted);
mOffset = mIsWide ? 9 : 6;
mCurrentTimeUs = 0;
mGroup = new MediaBufferGroup;
mGroup->add_buffer(new MediaBuffer(128));
mStarted = true;
return OK;
}
status_t AMRSource::stop() {
CHECK(mStarted);
delete mGroup;
mGroup = NULL;
mStarted = false;
return OK;
}
sp<MetaData> AMRSource::getFormat() {
return mMeta;
}
status_t AMRSource::read(
MediaBuffer **out, const ReadOptions *options) {
*out = NULL;
int64_t seekTimeUs;
ReadOptions::SeekMode mode;
if (options && options->getSeekTo(&seekTimeUs, &mode)) {
size_t size;
int64_t seekFrame = seekTimeUs / 20000ll; // 20ms per frame.
mCurrentTimeUs = seekFrame * 20000ll;
int index = seekFrame / 50;
if (index >= mOffsetTableLength) {
index = mOffsetTableLength - 1;
}
mOffset = mOffsetTable[index] + (mIsWide ? 9 : 6);
for (int i = 0; i< seekFrame - index * 50; i++) {
status_t err;
if ((err = getFrameSizeByOffset(mDataSource, mOffset,
mIsWide, &size)) != OK) {
return err;
}
mOffset += size;
}
}
uint8_t header;
ssize_t n = mDataSource->readAt(mOffset, &header, 1);
if (n < 1) {
return ERROR_END_OF_STREAM;
}
if (header & 0x83) {
// Padding bits must be 0.
ALOGE("padding bits must be 0, header is 0x%02x", header);
return ERROR_MALFORMED;
}
unsigned FT = (header >> 3) & 0x0f;
size_t frameSize = getFrameSize(mIsWide, FT);
if (frameSize == 0) {
return ERROR_MALFORMED;
}
MediaBuffer *buffer;
status_t err = mGroup->acquire_buffer(&buffer);
if (err != OK) {
return err;
}
n = mDataSource->readAt(mOffset, buffer->data(), frameSize);
if (n != (ssize_t)frameSize) {
buffer->release();
buffer = NULL;
return ERROR_IO;
}
buffer->set_range(0, frameSize);
buffer->meta_data()->setInt64(kKeyTime, mCurrentTimeUs);
buffer->meta_data()->setInt32(kKeyIsSyncFrame, 1);
mOffset += frameSize;
mCurrentTimeUs += 20000; // Each frame is 20ms
*out = buffer;
return OK;
}
////////////////////////////////////////////////////////////////////////////////
bool SniffAMR(
const sp<DataSource> &source, String8 *mimeType, float *confidence,
sp<AMessage> *) {
char header[9];
if (source->readAt(0, header, sizeof(header)) != sizeof(header)) {
return false;
}
if (!memcmp(header, "#!AMR\n", 6)) {
*mimeType = MEDIA_MIMETYPE_AUDIO_AMR_NB;
*confidence = 0.5;
return true;
} else if (!memcmp(header, "#!AMR-WB\n", 9)) {
*mimeType = MEDIA_MIMETYPE_AUDIO_AMR_WB;
*confidence = 0.5;
return true;
}
return false;
}
} // namespace android