Support key rotation when generating MP4 fragments

Change-Id: I472e03a2d41ee450c12c0fe3012904628d6893e7
This commit is contained in:
Kongqun Yang 2014-04-18 11:49:49 -07:00
parent 9076411044
commit 50ed026751
15 changed files with 424 additions and 128 deletions

View File

@ -219,8 +219,10 @@ bool RunPackager(const std::string& input) {
LOG(ERROR) << "FLAGS_track_type should be either 'SD' or 'HD'";
return false;
}
muxer->SetEncryptionKeySource(
encryption_key_source.get(), track_type, FLAGS_clear_lead);
muxer->SetEncryptionKeySource(encryption_key_source.get(),
track_type,
FLAGS_clear_lead,
FLAGS_crypto_period_duration);
// Start remuxing process.
status = demuxer.Run();

View File

@ -33,6 +33,10 @@ DEFINE_string(rsa_signing_key_path,
"",
"Stores PKCS#1 RSA private key for request signing. Exclusive "
"with --aes_signing_key.");
DEFINE_int32(crypto_period_duration,
0,
"Crypto period duration in seconds. If it is non-zero, key "
"rotation is enabled.");
static bool IsNotEmptyWithWidevineEncryption(const char* flag_name,
const std::string& flag_value) {

View File

@ -30,6 +30,13 @@ Status EncryptionKeySource::GetKey(TrackType track_type, EncryptionKey* key) {
return Status::OK;
}
Status EncryptionKeySource::GetCryptoPeriodKey(size_t crypto_period_index,
TrackType track_type,
EncryptionKey* key) {
NOTIMPLEMENTED();
return Status(error::UNIMPLEMENTED, "");
}
scoped_ptr<EncryptionKeySource> EncryptionKeySource::CreateFromHexStrings(
const std::string& key_id_hex,
const std::string& key_hex,

View File

@ -41,6 +41,12 @@ class EncryptionKeySource {
/// @return OK on success, an error status otherwise.
virtual Status GetKey(TrackType track_type, EncryptionKey* key);
/// Get encryption key of the specified track type at the specified index.
/// @return OK on success, an error status otherwise.
virtual Status GetCryptoPeriodKey(size_t crypto_period_index,
TrackType track_type,
EncryptionKey* key);
/// Create EncryptionKeySource object from hex strings.
/// @param key_id_hex is the key id in hex string.
/// @param key_hex is the key in hex string.

View File

@ -14,10 +14,11 @@ namespace media {
Muxer::Muxer(const MuxerOptions& options)
: options_(options),
encryption_key_source_(NULL),
initialized_(false),
encryption_key_source_(NULL),
track_type_(EncryptionKeySource::TRACK_TYPE_SD),
clear_lead_in_seconds_(0),
crypto_period_duration_in_seconds_(0),
muxer_listener_(NULL),
clock_(NULL) {}
@ -25,10 +26,13 @@ Muxer::~Muxer() {}
void Muxer::SetEncryptionKeySource(EncryptionKeySource* encryption_key_source,
EncryptionKeySource::TrackType track_type,
double clear_lead_in_seconds) {
double clear_lead_in_seconds,
double crypto_period_duration_in_seconds) {
DCHECK(encryption_key_source);
encryption_key_source_ = encryption_key_source;
track_type_ = track_type;
clear_lead_in_seconds_ = clear_lead_in_seconds;
crypto_period_duration_in_seconds_ = crypto_period_duration_in_seconds;
}
void Muxer::AddStream(MediaStream* stream) {

View File

@ -45,9 +45,13 @@ class Muxer {
/// @param track_type should be either SD or HD. It affects whether SD key or
/// HD key is used to encrypt the video content.
/// @param clear_lead_in_seconds specifies clear lead duration in seconds.
/// @param crypto_period_duration_in_seconds specifies crypto period duration
/// in seconds. A positive value means key rotation is enabled, the
/// key source must support key rotation in this case.
void SetEncryptionKeySource(EncryptionKeySource* encryption_key_source,
EncryptionKeySource::TrackType track_type,
double clear_lead_in_seconds);
double clear_lead_in_seconds,
double crypto_period_duration_in_seconds);
/// Add video/audio stream.
void AddStream(MediaStream* stream);
@ -78,6 +82,9 @@ class Muxer {
}
EncryptionKeySource::TrackType track_type() const { return track_type_; }
double clear_lead_in_seconds() const { return clear_lead_in_seconds_; }
double crypto_period_duration_in_seconds() const {
return crypto_period_duration_in_seconds_;
}
event::MuxerListener* muxer_listener() { return muxer_listener_; }
base::Clock* clock() { return clock_; }
@ -99,11 +106,12 @@ class Muxer {
scoped_refptr<MediaSample> sample) = 0;
MuxerOptions options_;
bool initialized_;
std::vector<MediaStream*> streams_;
EncryptionKeySource* encryption_key_source_;
bool initialized_;
EncryptionKeySource::TrackType track_type_;
double clear_lead_in_seconds_;
double crypto_period_duration_in_seconds_;
event::MuxerListener* muxer_listener_;
// An external injected clock, can be NULL.

View File

@ -9,11 +9,17 @@
#include "media/base/aes_encryptor.h"
#include "media/base/buffer_reader.h"
#include "media/base/buffer_writer.h"
#include "media/base/encryption_key_source.h"
#include "media/base/media_sample.h"
#include "media/formats/mp4/box_definitions.h"
#include "media/formats/mp4/cenc.h"
namespace media {
namespace mp4 {
namespace {
// Generate 64bit IV by default.
const size_t kDefaultIvSize = 8u;
const int64 kInvalidTime = kint64max;
// Optimize sample entries table. If all values in |entries| are identical,
@ -36,33 +42,48 @@ bool OptimizeSampleEntries(std::vector<T>* entries, T* default_value) {
*default_value = value;
return true;
}
} // namespace
namespace media {
namespace mp4 {
Fragmenter::Fragmenter(TrackFragment* traf,
scoped_ptr<AesCtrEncryptor> encryptor,
int64 clear_time,
uint8 nalu_length_size,
bool normalize_presentation_timestamp)
: encryptor_(encryptor.Pass()),
nalu_length_size_(nalu_length_size),
traf_(traf),
: traf_(traf),
nalu_length_size_(0),
clear_time_(0),
fragment_finalized_(false),
fragment_duration_(0),
normalize_presentation_timestamp_(normalize_presentation_timestamp),
presentation_start_time_(kInvalidTime),
earliest_presentation_time_(kInvalidTime),
first_sap_time_(kInvalidTime),
clear_time_(clear_time) {}
first_sap_time_(kInvalidTime) {
DCHECK(traf);
}
Fragmenter::Fragmenter(TrackFragment* traf,
bool normalize_presentation_timestamp,
scoped_ptr<EncryptionKey> encryption_key,
int64 clear_time,
uint8 nalu_length_size)
: traf_(traf),
encryption_key_(encryption_key.Pass()),
nalu_length_size_(nalu_length_size),
clear_time_(clear_time),
fragment_finalized_(false),
fragment_duration_(0),
normalize_presentation_timestamp_(normalize_presentation_timestamp),
presentation_start_time_(kInvalidTime),
earliest_presentation_time_(kInvalidTime),
first_sap_time_(kInvalidTime) {
DCHECK(traf);
DCHECK(encryption_key_);
}
Fragmenter::~Fragmenter() {}
Status Fragmenter::AddSample(scoped_refptr<MediaSample> sample) {
CHECK_GT(sample->duration(), 0);
if (ShouldEncryptFragment()) {
if (encryptor_) {
Status status = EncryptSample(sample);
if (!status.ok())
return status;
@ -112,11 +133,9 @@ Status Fragmenter::AddSample(scoped_refptr<MediaSample> sample) {
return Status::OK;
}
void Fragmenter::InitializeFragment() {
Status Fragmenter::InitializeFragment() {
fragment_finalized_ = false;
traf_->decode_time.decode_time += fragment_duration_;
traf_->auxiliary_size.sample_info_sizes.clear();
traf_->auxiliary_offset.offsets.clear();
traf_->runs.clear();
traf_->runs.resize(1);
traf_->runs[0].flags = TrackFragmentRun::kDataOffsetPresentMask;
@ -127,41 +146,28 @@ void Fragmenter::InitializeFragment() {
data_.reset(new BufferWriter());
aux_data_.reset(new BufferWriter());
if (ShouldEncryptFragment()) {
if (!IsSubsampleEncryptionRequired()) {
DCHECK(encryptor_);
traf_->auxiliary_size.default_sample_info_size = encryptor_->iv().size();
}
}
if (!encryption_key_)
return Status::OK;
// Enable encryption for this fragment if decode time passes clear lead.
if (static_cast<int64>(traf_->decode_time.decode_time) >= clear_time_)
return PrepareFragmentForEncryption();
// Otherwise, this fragment should be in clear text.
// We generate at most two sample description entries, encrypted entry and
// clear entry. The 1-based clear entry index is always 2.
const uint32 kClearSampleDescriptionIndex = 2;
traf_->header.flags |=
TrackFragmentHeader::kSampleDescriptionIndexPresentMask;
traf_->header.sample_description_index = kClearSampleDescriptionIndex;
return Status::OK;
}
void Fragmenter::FinalizeFragment() {
if (ShouldEncryptFragment()) {
DCHECK(encryptor_);
// The offset will be adjusted in Segmenter when we know moof size.
traf_->auxiliary_offset.offsets.push_back(0);
// Optimize saiz box.
SampleAuxiliaryInformationSize& saiz = traf_->auxiliary_size;
saiz.sample_count = traf_->runs[0].sample_sizes.size();
if (!saiz.sample_info_sizes.empty()) {
if (!OptimizeSampleEntries(&saiz.sample_info_sizes,
&saiz.default_sample_info_size)) {
saiz.default_sample_info_size = 0;
}
}
} else if (encryptor_ && clear_time_ > 0) {
// This fragment should be in clear.
// We generate at most two sample description entries, encrypted entry and
// clear entry. The 1-based clear entry index is always 2.
const uint32 kClearSampleDescriptionIndex = 2;
traf_->header.flags |=
TrackFragmentHeader::kSampleDescriptionIndexPresentMask;
traf_->header.sample_description_index = kClearSampleDescriptionIndex;
clear_time_ -= fragment_duration_;
}
if (encryptor_)
FinalizeFragmentForEncryption();
// Optimize trun box.
traf_->runs[0].sample_count = traf_->runs[0].sample_sizes.size();
@ -203,6 +209,47 @@ void Fragmenter::GenerateSegmentReference(SegmentReference* reference) {
reference->earliest_presentation_time = earliest_presentation_time_;
}
Status Fragmenter::PrepareFragmentForEncryption() {
traf_->auxiliary_size.sample_info_sizes.clear();
traf_->auxiliary_offset.offsets.clear();
return encryptor_ ? Status::OK : CreateEncryptor();
}
void Fragmenter::FinalizeFragmentForEncryption() {
// The offset will be adjusted in Segmenter when we know moof size.
traf_->auxiliary_offset.offsets.push_back(0);
// Optimize saiz box.
SampleAuxiliaryInformationSize& saiz = traf_->auxiliary_size;
saiz.sample_count = traf_->runs[0].sample_sizes.size();
if (!saiz.sample_info_sizes.empty()) {
if (!OptimizeSampleEntries(&saiz.sample_info_sizes,
&saiz.default_sample_info_size)) {
saiz.default_sample_info_size = 0;
}
} else {
// |sample_info_sizes| table is filled in only for subsample encryption,
// otherwise |sample_info_size| is just the IV size.
DCHECK(!IsSubsampleEncryptionRequired());
saiz.default_sample_info_size = encryptor_->iv().size();
}
}
Status Fragmenter::CreateEncryptor() {
DCHECK(encryption_key_);
scoped_ptr<AesCtrEncryptor> encryptor(new AesCtrEncryptor());
const bool initialized = encryption_key_->iv.empty()
? encryptor->InitializeWithRandomIv(
encryption_key_->key, kDefaultIvSize)
: encryptor->InitializeWithIv(
encryption_key_->key, encryption_key_->iv);
if (!initialized)
return Status(error::MUXER_FAILURE, "Failed to create the encryptor.");
encryptor_ = encryptor.Pass();
return Status::OK;
}
void Fragmenter::EncryptBytes(uint8* data, uint32 size) {
DCHECK(encryptor_);
CHECK(encryptor_->Encrypt(data, size, data));

View File

@ -19,8 +19,11 @@ class AesCtrEncryptor;
class BufferWriter;
class MediaSample;
struct EncryptionKey;
namespace mp4 {
struct MovieFragment;
struct SegmentReference;
struct TrackFragment;
@ -30,26 +33,33 @@ struct TrackFragment;
class Fragmenter {
public:
/// @param traf points to a TrackFragment box.
/// @param encryptor handles encryption of the samples. It can be NULL, which
/// indicates no encryption is required.
/// @param normalize_presentation_timestamp defines whether PTS should be
/// normalized to start from zero.
Fragmenter(TrackFragment* traf,
bool normalize_presentation_timestamp);
/// @param traf points to a TrackFragment box.
/// @param normalize_presentation_timestamp defines whether PTS should be
/// normalized to start from zero.
/// @param encryption_key contains the encryption parameters.
/// @param clear_time specifies clear lead duration in units of the current
/// track's timescale.
/// @param nalu_length_size NAL unit length size, in bytes, for subsample
/// encryption.
/// @param normalize_presentation_timestamp defines whether PTS should be
/// normalized to start from zero.
Fragmenter(TrackFragment* traf,
scoped_ptr<AesCtrEncryptor> encryptor,
bool normalize_presentation_timestamp,
scoped_ptr<EncryptionKey> encryption_key,
int64 clear_time,
uint8 nalu_length_size,
bool normalize_presentation_timestamp);
~Fragmenter();
uint8 nalu_length_size);
virtual ~Fragmenter();
/// Add a sample to the fragmenter.
Status AddSample(scoped_refptr<MediaSample> sample);
/// Initialize the fragment with default data.
void InitializeFragment();
/// @return OK on success, an error status otherwise.
Status InitializeFragment();
/// Finalize and optimize the fragment.
void FinalizeFragment();
@ -66,34 +76,52 @@ class Fragmenter {
BufferWriter* data() { return data_.get(); }
BufferWriter* aux_data() { return aux_data_.get(); }
protected:
/// Prepare current fragment for encryption.
/// @return OK on success, an error status otherwise.
virtual Status PrepareFragmentForEncryption();
/// Finalize current fragment for encryption.
virtual void FinalizeFragmentForEncryption();
/// Create the encryptor for the internal encryption key. The existing
/// encryptor will be reset if it is not NULL.
/// @return OK on success, an error status otherwise.
Status CreateEncryptor();
TrackFragment* traf() { return traf_; }
EncryptionKey* encryption_key() { return encryption_key_.get(); }
AesCtrEncryptor* encryptor() { return encryptor_.get(); }
void set_encryption_key(scoped_ptr<EncryptionKey> encryption_key) {
encryption_key_ = encryption_key.Pass();
}
private:
void EncryptBytes(uint8* data, uint32 size);
Status EncryptSample(scoped_refptr<MediaSample> sample);
// Should we enable encrytion for the current fragment?
bool ShouldEncryptFragment() {
return (encryptor_ != NULL && clear_time_ <= 0);
}
// Should we enable subsample encryption?
bool IsSubsampleEncryptionRequired() { return nalu_length_size_ != 0; }
// Check if the current fragment starts with SAP.
bool StartsWithSAP();
TrackFragment* traf_;
scoped_ptr<EncryptionKey> encryption_key_;
scoped_ptr<AesCtrEncryptor> encryptor_;
// If this stream contains AVC, subsample encryption specifies that the size
// and type of NAL units remain unencrypted. This field specifies the size of
// the size field. Can be 1, 2 or 4 bytes.
uint8 nalu_length_size_;
TrackFragment* traf_;
const uint8 nalu_length_size_;
const int64 clear_time_;
bool fragment_finalized_;
uint64 fragment_duration_;
bool normalize_presentation_timestamp_;
int64 presentation_start_time_;
int64 earliest_presentation_time_;
int64 first_sap_time_;
int64 clear_time_;
scoped_ptr<BufferWriter> data_;
scoped_ptr<BufferWriter> aux_data_;

View File

@ -0,0 +1,100 @@
// Copyright 2014 Google Inc. All rights reserved.
//
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file or at
// https://developers.google.com/open-source/licenses/bsd
#include "media/formats/mp4/key_rotation_fragmenter.h"
#include "media/base/aes_encryptor.h"
#include "media/formats/mp4/box_definitions.h"
namespace media {
namespace mp4 {
KeyRotationFragmenter::KeyRotationFragmenter(
MovieFragment* moof,
TrackFragment* traf,
bool normalize_presentation_timestamp,
EncryptionKeySource* encryption_key_source,
EncryptionKeySource::TrackType track_type,
int64 crypto_period_duration,
int64 clear_time,
uint8 nalu_length_size)
: Fragmenter(traf,
normalize_presentation_timestamp,
scoped_ptr<EncryptionKey>(new EncryptionKey()),
clear_time,
nalu_length_size),
moof_(moof),
encryption_key_source_(encryption_key_source),
track_type_(track_type),
crypto_period_duration_(crypto_period_duration),
prev_crypto_period_index_(-1) {
DCHECK(moof);
DCHECK(encryption_key_source);
}
KeyRotationFragmenter::~KeyRotationFragmenter() {}
Status KeyRotationFragmenter::PrepareFragmentForEncryption() {
traf()->auxiliary_size.sample_info_sizes.clear();
traf()->auxiliary_offset.offsets.clear();
size_t current_crypto_period_index =
traf()->decode_time.decode_time / crypto_period_duration_;
if (current_crypto_period_index != prev_crypto_period_index_) {
scoped_ptr<EncryptionKey> encryption_key(new EncryptionKey());
Status status = encryption_key_source_->GetCryptoPeriodKey(
current_crypto_period_index, track_type_, encryption_key.get());
if (!status.ok())
return status;
set_encryption_key(encryption_key.Pass());
status = CreateEncryptor();
if (!status.ok())
return status;
prev_crypto_period_index_ = current_crypto_period_index;
}
EncryptionKey* encryption_key = Fragmenter::encryption_key();
DCHECK(encryption_key);
AesCtrEncryptor* encryptor = Fragmenter::encryptor();
DCHECK(encryptor);
// We support key rotation in fragment boundary only, i.e. there is at most
// one key for a single fragment. So we should have only one entry in
// Sample Group Description box and one entry in Sample to Group box.
// Fill in Sample Group Description box information.
traf()->sample_group_description.grouping_type = FOURCC_SEIG;
traf()->sample_group_description.entries.resize(1);
traf()->sample_group_description.entries[0].is_encrypted = true;
traf()->sample_group_description.entries[0].iv_size = encryptor->iv().size();
traf()->sample_group_description.entries[0].key_id = encryption_key->key_id;
// Fill in Sample to Group box information.
traf()->sample_to_group.grouping_type = FOURCC_SEIG;
traf()->sample_to_group.entries.resize(1);
// sample_count is adjusted in |FinalizeFragment| later.
traf()->sample_to_group.entries[0].group_description_index =
SampleToGroupEntry::kTrackFragmentGroupDescriptionIndexBase + 1;
// We need one and only one pssh box.
if (moof_->pssh.empty())
moof_->pssh.resize(1);
moof_->pssh[0].raw_box = encryption_key->pssh;
return Status::OK;
}
void KeyRotationFragmenter::FinalizeFragmentForEncryption() {
Fragmenter::FinalizeFragmentForEncryption();
DCHECK_EQ(1u, traf()->sample_to_group.entries.size());
traf()->sample_to_group.entries[0].sample_count =
traf()->auxiliary_size.sample_count;
}
} // namespace media
} // namespace mp4

View File

@ -0,0 +1,63 @@
// Copyright 2014 Google Inc. All rights reserved.
//
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file or at
// https://developers.google.com/open-source/licenses/bsd
#ifndef MEDIA_FORMATS_MP4_KEY_ROTATION_FRAGMENTER_H_
#define MEDIA_FORMATS_MP4_KEY_ROTATION_FRAGMENTER_H_
#include "media/base/encryption_key_source.h"
#include "media/formats/mp4/fragmenter.h"
namespace media {
namespace mp4 {
class KeyRotationFragmenter : public Fragmenter {
public:
/// @param moof points to a MovieFragment box.
/// @param traf points to a TrackFragment box.
/// @param normalize_presentation_timestamp defines whether PTS should be
/// normalized to start from zero.
/// @param encryption_key_source points to the source which generates
/// encryption keys.
/// @param track_type indicates whether SD key or HD key should be used to
/// encrypt the video content.
/// @param crypto_period_duration specifies crypto period duration in units
/// of the current track's timescale.
/// @param clear_time specifies clear lead duration in units of the current
/// track's timescale.
/// @param nalu_length_size NAL unit length size, in bytes, for subsample
/// encryption.
KeyRotationFragmenter(MovieFragment* moof,
TrackFragment* traf,
bool normalize_presentation_timestamp,
EncryptionKeySource* encryption_key_source,
EncryptionKeySource::TrackType track_type,
int64 crypto_period_duration,
int64 clear_time,
uint8 nalu_length_size);
virtual ~KeyRotationFragmenter();
protected:
/// @name Fragmenter implementation overrides.
/// @{
virtual Status PrepareFragmentForEncryption() OVERRIDE;
virtual void FinalizeFragmentForEncryption() OVERRIDE;
/// @}
private:
MovieFragment* moof_;
EncryptionKeySource* encryption_key_source_;
EncryptionKeySource::TrackType track_type_;
const int64 crypto_period_duration_;
size_t prev_crypto_period_index_;
DISALLOW_COPY_AND_ASSIGN(KeyRotationFragmenter);
};
} // namespace mp4
} // namespace media
#endif // MEDIA_FORMATS_MP4_KEY_ROTATION_FRAGMENTER_H_

View File

@ -42,6 +42,8 @@
'fourccs.h',
'fragmenter.cc',
'fragmenter.h',
'key_rotation_fragmenter.cc',
'key_rotation_fragmenter.h',
'mp4_media_parser.cc',
'mp4_media_parser.h',
'mp4_muxer.cc',

View File

@ -102,7 +102,8 @@ Status MP4Muxer::Initialize() {
segmenter_->Initialize(streams(),
encryption_key_source(),
track_type(),
clear_lead_in_seconds());
clear_lead_in_seconds(),
crypto_period_duration_in_seconds());
if (!segmenter_initialized.ok())
return segmenter_initialized;

View File

@ -9,7 +9,6 @@
#include <algorithm>
#include "base/stl_util.h"
#include "media/base/aes_encryptor.h"
#include "media/base/buffer_writer.h"
#include "media/base/encryption_key_source.h"
#include "media/base/media_sample.h"
@ -17,7 +16,7 @@
#include "media/base/muxer_options.h"
#include "media/base/video_stream_info.h"
#include "media/formats/mp4/box_definitions.h"
#include "media/formats/mp4/fragmenter.h"
#include "media/formats/mp4/key_rotation_fragmenter.h"
namespace media {
namespace mp4 {
@ -26,6 +25,7 @@ namespace {
// Generate 64bit IV by default.
const size_t kDefaultIvSize = 8u;
const size_t kCencKeyIdSize = 16u;
// The version of cenc implemented here. CENC 4.
const int kCencSchemeVersion = 0x00010000;
@ -34,21 +34,6 @@ uint64 Rescale(uint64 time_in_old_scale, uint32 old_scale, uint32 new_scale) {
return static_cast<double>(time_in_old_scale) / old_scale * new_scale;
}
scoped_ptr<AesCtrEncryptor> CreateEncryptor(
const EncryptionKey& encryption_key) {
scoped_ptr<AesCtrEncryptor> encryptor(new AesCtrEncryptor());
const bool initialized =
encryption_key.iv.empty()
? encryptor->InitializeWithRandomIv(encryption_key.key,
kDefaultIvSize)
: encryptor->InitializeWithIv(encryption_key.key, encryption_key.iv);
if (!initialized) {
LOG(ERROR) << "Failed to the initialize encryptor.";
return scoped_ptr<AesCtrEncryptor>();
}
return encryptor.Pass();
}
void GenerateSinf(const EncryptionKey& encryption_key,
FourCC old_type,
ProtectionSchemeInfo* sinf) {
@ -91,6 +76,16 @@ void GenerateEncryptedSampleEntry(const EncryptionKey& encryption_key,
}
}
void GenerateEncryptedSampleEntryForKeyRotation(
double clear_lead_in_seconds,
SampleDescription* description) {
// Fill encrypted sample entry with default key.
EncryptionKey encryption_key;
encryption_key.key_id.assign(kCencKeyIdSize, 0);
GenerateEncryptedSampleEntry(
encryption_key, clear_lead_in_seconds, description);
}
} // namespace
Segmenter::Segmenter(const MuxerOptions& options,
@ -110,7 +105,8 @@ Segmenter::~Segmenter() { STLDeleteElements(&fragmenters_); }
Status Segmenter::Initialize(const std::vector<MediaStream*>& streams,
EncryptionKeySource* encryption_key_source,
EncryptionKeySource::TrackType track_type,
double clear_lead_in_seconds) {
double clear_lead_in_seconds,
double crypto_period_duration_in_seconds) {
DCHECK_LT(0u, streams.size());
moof_->header.sequence_number = 0;
@ -129,41 +125,59 @@ Status Segmenter::Initialize(const std::vector<MediaStream*>& streams,
if (sidx_->reference_id == 0)
sidx_->reference_id = i + 1;
}
scoped_ptr<AesCtrEncryptor> encryptor;
if (encryption_key_source) {
SampleDescription& description =
moov_->tracks[i].media.information.sample_table.description;
DCHECK(track_type == EncryptionKeySource::TRACK_TYPE_SD ||
track_type == EncryptionKeySource::TRACK_TYPE_HD);
EncryptionKey encryption_key;
Status status = encryption_key_source->GetKey(
description.type == kAudio ? EncryptionKeySource::TRACK_TYPE_AUDIO
: track_type,
&encryption_key);
if (!status.ok())
return status;
GenerateEncryptedSampleEntry(
encryption_key, clear_lead_in_seconds, &description);
// We need one and only one pssh box.
if (moov_->pssh.empty()) {
moov_->pssh.resize(1);
moov_->pssh[0].raw_box = encryption_key.pssh;
}
encryptor = CreateEncryptor(encryption_key);
if (!encryptor)
return Status(error::MUXER_FAILURE, "Failed to create the encryptor.");
if (!encryption_key_source) {
fragmenters_[i] = new Fragmenter(
&moof_->tracks[i], options_.normalize_presentation_timestamp);
continue;
}
fragmenters_[i] = new Fragmenter(
&moof_->tracks[i],
encryptor.Pass(),
clear_lead_in_seconds * streams[i]->info()->time_scale(),
nalu_length_size,
options_.normalize_presentation_timestamp);
DCHECK(track_type == EncryptionKeySource::TRACK_TYPE_SD ||
track_type == EncryptionKeySource::TRACK_TYPE_HD);
SampleDescription& description =
moov_->tracks[i].media.information.sample_table.description;
EncryptionKeySource::TrackType cur_track_type =
description.type == kAudio ? EncryptionKeySource::TRACK_TYPE_AUDIO
: track_type;
const bool key_rotation_enabled = crypto_period_duration_in_seconds != 0;
if (key_rotation_enabled) {
GenerateEncryptedSampleEntryForKeyRotation(clear_lead_in_seconds,
&description);
fragmenters_[i] = new KeyRotationFragmenter(
moof_.get(),
&moof_->tracks[i],
options_.normalize_presentation_timestamp,
encryption_key_source,
cur_track_type,
crypto_period_duration_in_seconds * streams[i]->info()->time_scale(),
clear_lead_in_seconds * streams[i]->info()->time_scale(),
nalu_length_size);
continue;
}
scoped_ptr<EncryptionKey> encryption_key(new EncryptionKey());
Status status =
encryption_key_source->GetKey(cur_track_type, encryption_key.get());
if (!status.ok())
return status;
GenerateEncryptedSampleEntry(
*encryption_key, clear_lead_in_seconds, &description);
// We need one and only one pssh box.
if (moov_->pssh.empty()) {
moov_->pssh.resize(1);
moov_->pssh[0].raw_box = encryption_key->pssh;
}
fragmenters_[i] =
new Fragmenter(&moof_->tracks[i],
options_.normalize_presentation_timestamp,
encryption_key.Pass(),
clear_lead_in_seconds * streams[i]->info()->time_scale(),
nalu_length_size);
}
// Choose the first stream if there is no VIDEO.
@ -289,13 +303,17 @@ uint32 Segmenter::GetReferenceStreamId() {
return sidx_->reference_id - 1;
}
void Segmenter::InitializeFragments() {
Status Segmenter::InitializeFragments() {
++moof_->header.sequence_number;
Status status;
for (std::vector<Fragmenter*>::iterator it = fragmenters_.begin();
it != fragmenters_.end();
++it) {
(*it)->InitializeFragment();
status = (*it)->InitializeFragment();
if (!status.ok())
return status;
}
return Status::OK;
}
Status Segmenter::FinalizeFragment(Fragmenter* fragmenter) {

View File

@ -49,17 +49,20 @@ class Segmenter {
/// Initialize the segmenter.
/// Calling other public methods of this class without this method returning
/// Status::OK results in an undefined behavior.
/// @param streams contains the vector of MediaStreams to be segmented.
/// @param encryption_key_source points to the key source which contains
/// the encryption keys. It can be NULL to indicate that no encryption
/// is required.
/// @param track_type indicates whether SD key or HD key should be used to
/// encrypt the video content.
/// @param clear_time specifies clear lead duration in seconds.
/// @param crypto_period_duration specifies crypto period duration in seconds.
/// @return OK on success, an error status otherwise.
Status Initialize(const std::vector<MediaStream*>& streams,
EncryptionKeySource* encryption_key_source,
EncryptionKeySource::TrackType track_type,
double clear_lead_in_seconds);
double clear_lead_in_seconds,
double crypto_period_duration_in_seconds);
/// Finalize the segmenter.
/// @return OK on success, an error status otherwise.
@ -102,7 +105,7 @@ class Segmenter {
Status FinalizeSegment();
uint32 GetReferenceStreamId();
void InitializeFragments();
Status InitializeFragments();
Status FinalizeFragment(Fragmenter* fragment);
const MuxerOptions& options_;

View File

@ -54,6 +54,7 @@ const char kPsshHex[] =
"758382cd1a0d7769646576696e655f746573742211544553545f"
"434f4e54454e545f49445f312a025344";
const double kClearLeadInSeconds = 1.5;
const double kCryptoDurationInSeconds = 0; // Key rotation is disabled.
MediaStream* FindFirstStreamOfType(const std::vector<MediaStream*>& streams,
StreamType stream_type) {
@ -164,7 +165,8 @@ void PackagerTestBasic::Remux(const std::string& input,
if (enable_encryption) {
muxer_video->SetEncryptionKeySource(encryption_key_source.get(),
EncryptionKeySource::TRACK_TYPE_SD,
kClearLeadInSeconds);
kClearLeadInSeconds,
kCryptoDurationInSeconds);
}
}
@ -179,7 +181,8 @@ void PackagerTestBasic::Remux(const std::string& input,
if (enable_encryption) {
muxer_audio->SetEncryptionKeySource(encryption_key_source.get(),
EncryptionKeySource::TRACK_TYPE_SD,
kClearLeadInSeconds);
kClearLeadInSeconds,
kCryptoDurationInSeconds);
}
}