Mirror-Tools
/
shaka-packager
mirror of https://github.com/shaka-project/shaka-packager.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity
shaka-packager/packager/media/formats/mp4/mp4_muxer.cc

625 lines
23 KiB
C++
Raw Permalink Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

// 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 "packager/media/formats/mp4/mp4_muxer.h"
#include <algorithm>
#include "packager/base/time/clock.h"
#include "packager/base/time/time.h"
#include "packager/file/file.h"
#include "packager/media/base/aes_encryptor.h"
#include "packager/media/base/audio_stream_info.h"
#include "packager/media/base/fourccs.h"
#include "packager/media/base/key_source.h"
#include "packager/media/base/media_sample.h"
#include "packager/media/base/text_stream_info.h"
#include "packager/media/base/video_stream_info.h"
#include "packager/media/codecs/es_descriptor.h"
#include "packager/media/event/muxer_listener.h"
#include "packager/media/formats/mp4/box_definitions.h"
#include "packager/media/formats/mp4/multi_segment_segmenter.h"
#include "packager/media/formats/mp4/single_segment_segmenter.h"
#include "packager/status_macros.h"
namespace shaka {
namespace media {
namespace mp4 {
namespace {
// Sets the range start and end value from offset and size.
// |start| and |end| are for byte-range-spec specified in RFC2616.
void SetStartAndEndFromOffsetAndSize(size_t offset,
size_t size,
Range* range) {
DCHECK(range);
range->start = static_cast<uint32_t>(offset);
// Note that ranges are inclusive. So we need - 1.
range->end = range->start + static_cast<uint32_t>(size) - 1;
}
FourCC CodecToFourCC(Codec codec, H26xStreamFormat h26x_stream_format) {
switch (codec) {
case kCodecAV1:
return FOURCC_av01;
case kCodecH264:
return h26x_stream_format ==
H26xStreamFormat::kNalUnitStreamWithParameterSetNalus
? FOURCC_avc3
: FOURCC_avc1;
case kCodecH265:
return h26x_stream_format ==
H26xStreamFormat::kNalUnitStreamWithParameterSetNalus
? FOURCC_hev1
: FOURCC_hvc1;
case kCodecVP8:
return FOURCC_vp08;
case kCodecVP9:
return FOURCC_vp09;
case kCodecAAC:
return FOURCC_mp4a;
case kCodecAC3:
return FOURCC_ac_3;
case kCodecDTSC:
return FOURCC_dtsc;
case kCodecDTSH:
return FOURCC_dtsh;
case kCodecDTSL:
return FOURCC_dtsl;
case kCodecDTSE:
return FOURCC_dtse;
case kCodecDTSM:
return FOURCC_dtsm;
case kCodecEAC3:
return FOURCC_ec_3;
case kCodecFlac:
return FOURCC_fLaC;
case kCodecOpus:
return FOURCC_Opus;
default:
return FOURCC_NULL;
}
}
void GenerateSinf(FourCC old_type,
const EncryptionConfig& encryption_config,
ProtectionSchemeInfo* sinf) {
sinf->format.format = old_type;
DCHECK_NE(encryption_config.protection_scheme, FOURCC_NULL);
sinf->type.type = encryption_config.protection_scheme;
// The version of cenc implemented here. CENC 4.
const int kCencSchemeVersion = 0x00010000;
sinf->type.version = kCencSchemeVersion;
auto& track_encryption = sinf->info.track_encryption;
track_encryption.default_is_protected = 1;
track_encryption.default_crypt_byte_block =
encryption_config.crypt_byte_block;
track_encryption.default_skip_byte_block = encryption_config.skip_byte_block;
switch (encryption_config.protection_scheme) {
case FOURCC_cenc:
case FOURCC_cbc1:
DCHECK_EQ(track_encryption.default_crypt_byte_block, 0u);
DCHECK_EQ(track_encryption.default_skip_byte_block, 0u);
// CENCv3 10.1 ‘cenc’ AES-CTR scheme and 10.2 ‘cbc1’ AES-CBC scheme:
// The version of the Track Encryption Box (‘tenc’) SHALL be 0.
track_encryption.version = 0;
break;
case FOURCC_cbcs:
case FOURCC_cens:
// CENCv3 10.3 ‘cens’ AES-CTR subsample pattern encryption scheme and
// 10.4 ‘cbcs’ AES-CBC subsample pattern encryption scheme:
// The version of the Track Encryption Box (‘tenc’) SHALL be 1.
track_encryption.version = 1;
break;
default:
NOTREACHED() << "Unexpected protection scheme "
<< encryption_config.protection_scheme;
}
track_encryption.default_per_sample_iv_size =
encryption_config.per_sample_iv_size;
track_encryption.default_constant_iv = encryption_config.constant_iv;
track_encryption.default_kid = encryption_config.key_id;
}
// The roll distance is expressed in sample units and always takes negative
// values.
int16_t GetRollDistance(uint64_t seek_preroll_ns, uint32_t sampling_frequency) {
const double kNanosecondsPerSecond = 1000000000;
const double preroll_in_samples =
seek_preroll_ns / kNanosecondsPerSecond * sampling_frequency;
// Round to closest integer.
return -static_cast<int16_t>(preroll_in_samples + 0.5);
}
} // namespace
MP4Muxer::MP4Muxer(const MuxerOptions& options) : Muxer(options) {}
MP4Muxer::~MP4Muxer() {}
Status MP4Muxer::InitializeMuxer() {
// Muxer will be delay-initialized after seeing the first sample.
to_be_initialized_ = true;
return Status::OK;
}
Status MP4Muxer::Finalize() {
// This happens on streams that are not initialized, i.e. not going through
// DelayInitializeMuxer, which can only happen if there are no samples from
// the stream.
if (!segmenter_) {
DCHECK(to_be_initialized_);
LOG(INFO) << "Skip stream '" << options().output_file_name
<< "' which does not contain any sample.";
return Status::OK;
}
Status segmenter_finalized = segmenter_->Finalize();
if (!segmenter_finalized.ok())
return segmenter_finalized;
FireOnMediaEndEvent();
LOG(INFO) << "MP4 file '" << options().output_file_name << "' finalized.";
return Status::OK;
}
Status MP4Muxer::AddSample(size_t stream_id, const MediaSample& sample) {
if (to_be_initialized_) {
RETURN_IF_ERROR(UpdateEditListOffsetFromSample(sample));
RETURN_IF_ERROR(DelayInitializeMuxer());
to_be_initialized_ = false;
}
DCHECK(segmenter_);
return segmenter_->AddSample(stream_id, sample);
}
Status MP4Muxer::FinalizeSegment(size_t stream_id,
const SegmentInfo& segment_info) {
DCHECK(segmenter_);
VLOG(3) << "Finalizing " << (segment_info.is_subsegment ? "sub" : "")
<< "segment " << segment_info.start_timestamp << " duration "
<< segment_info.duration;
return segmenter_->FinalizeSegment(stream_id, segment_info);
}
Status MP4Muxer::DelayInitializeMuxer() {
DCHECK(!streams().empty());
std::unique_ptr<FileType> ftyp(new FileType);
std::unique_ptr<Movie> moov(new Movie);
ftyp->major_brand = FOURCC_isom;
ftyp->compatible_brands.push_back(FOURCC_iso8);
ftyp->compatible_brands.push_back(FOURCC_mp41);
ftyp->compatible_brands.push_back(FOURCC_dash);
if (streams().size() == 1) {
FourCC codec_fourcc = FOURCC_NULL;
if (streams()[0]->stream_type() == kStreamVideo) {
codec_fourcc =
CodecToFourCC(streams()[0]->codec(),
static_cast<const VideoStreamInfo*>(streams()[0].get())
->h26x_stream_format());
if (codec_fourcc != FOURCC_NULL)
ftyp->compatible_brands.push_back(codec_fourcc);
}
// CMAF allows only one track/stream per file.
// CMAF requires single initialization switching for AVC3/HEV1, which is not
// supported yet.
if (codec_fourcc != FOURCC_avc3 && codec_fourcc != FOURCC_hev1)
ftyp->compatible_brands.push_back(FOURCC_cmfc);
}
moov->header.creation_time = IsoTimeNow();
moov->header.modification_time = IsoTimeNow();
moov->header.next_track_id = static_cast<uint32_t>(streams().size()) + 1;
moov->tracks.resize(streams().size());
moov->extends.tracks.resize(streams().size());
// Initialize tracks.
for (uint32_t i = 0; i < streams().size(); ++i) {
const StreamInfo* stream = streams()[i].get();
Track& trak = moov->tracks[i];
trak.header.track_id = i + 1;
TrackExtends& trex = moov->extends.tracks[i];
trex.track_id = trak.header.track_id;
trex.default_sample_description_index = 1;
bool generate_trak_result = false;
switch (stream->stream_type()) {
case kStreamVideo:
generate_trak_result = GenerateVideoTrak(
static_cast<const VideoStreamInfo*>(stream), &trak, i + 1);
break;
case kStreamAudio:
generate_trak_result = GenerateAudioTrak(
static_cast<const AudioStreamInfo*>(stream), &trak, i + 1);
break;
case kStreamText:
generate_trak_result = GenerateTextTrak(
static_cast<const TextStreamInfo*>(stream), &trak, i + 1);
break;
default:
NOTIMPLEMENTED() << "Not implemented for stream type: "
<< stream->stream_type();
}
if (!generate_trak_result)
return Status(error::MUXER_FAILURE, "Failed to generate trak.");
// Generate EditList if needed. See UpdateEditListOffsetFromSample() for
// more information.
if (edit_list_offset_.value() > 0) {
EditListEntry entry;
entry.media_time = edit_list_offset_.value();
entry.media_rate_integer = 1;
trak.edit.list.edits.push_back(entry);
}
if (stream->is_encrypted() && options().mp4_params.include_pssh_in_stream) {
moov->pssh.clear();
const auto& key_system_info = stream->encryption_config().key_system_info;
for (const ProtectionSystemSpecificInfo& system : key_system_info) {
if (system.psshs.empty())
continue;
ProtectionSystemSpecificHeader pssh;
pssh.raw_box = system.psshs;
moov->pssh.push_back(pssh);
}
}
}
if (options().segment_template.empty()) {
segmenter_.reset(new SingleSegmentSegmenter(options(), std::move(ftyp),
std::move(moov)));
} else {
segmenter_.reset(
new MultiSegmentSegmenter(options(), std::move(ftyp), std::move(moov)));
}
const Status segmenter_initialized =
segmenter_->Initialize(streams(), muxer_listener(), progress_listener());
if (!segmenter_initialized.ok())
return segmenter_initialized;
FireOnMediaStartEvent();
return Status::OK;
}
Status MP4Muxer::UpdateEditListOffsetFromSample(const MediaSample& sample) {
if (edit_list_offset_)
return Status::OK;
const int64_t pts = sample.pts();
const int64_t dts = sample.dts();
// An EditList entry is inserted if one of the below conditions occur [4]:
// (1) pts > dts for the first sample. Due to Chrome's dts bug [1], dts is
// used in buffered range API, while pts is used elsewhere (players,
// manifests, and Chrome's own appendWindow check etc.), this
// inconsistency creates various problems, including possible stalls
// during playback. Since Chrome adjusts pts only when seeing EditList
// [2], we can insert an EditList with the time equal to difference of pts
// and dts to make aligned buffered ranges using pts and dts. This
// effectively workarounds the dts bug. It is also recommended by ISO-BMFF
// specification [3].
// (2) pts == dts and with pts < 0. This happens for some audio codecs where a
// negative presentation timestamp signals that the sample is not supposed
// to be shown, i.e. for audio priming. EditList is needed to encode
// negative timestamps.
// [1] https://crbug.com/718641, fixed but behind MseBufferByPts, still not
// enabled as of M67.
// [2] This is actually a bug, see https://crbug.com/354518. It looks like
// Chrome is planning to enable the fix for [1] before addressing this
// bug, so we are safe.
// [3] ISO 14496-12:2015 8.6.6.1
// It is recommended that such an edit be used to establish a presentation
// time of 0 for the first presented sample, when composition offsets are
// used.
// [4] ISO 23009-19:2018 7.5.13
// In two cases, an EditBox containing a single EditListBox with the
// following constraints may be present in the CMAF header of a CMAF track
// to adjust the presentation time of all media samples in the CMAF track.
// a) The first case is a video CMAF track file using v0 TrackRunBoxes
// with positive composition offsets to reorder video media samples.
// b) The second case is an audio CMAF track where each media sample's
// presentation time does not equal its composition time.
const int64_t pts_dts_offset = pts - dts;
if (pts_dts_offset > 0) {
if (pts < 0) {
LOG(ERROR) << "Negative presentation timestamp (" << pts
<< ") is not supported when there is an offset between "
"presentation timestamp and decoding timestamp ("
<< dts << ").";
return Status(error::MUXER_FAILURE,
"Unsupported negative pts when there is an offset between "
"pts and dts.");
}
edit_list_offset_ = pts_dts_offset;
return Status::OK;
}
if (pts_dts_offset < 0) {
LOG(ERROR) << "presentation timestamp (" << pts
<< ") is not supposed to be greater than decoding timestamp ("
<< dts << ").";
return Status(error::MUXER_FAILURE, "Not expecting pts < dts.");
}
edit_list_offset_ = std::max(-sample.pts(), static_cast<int64_t>(0));
return Status::OK;
}
void MP4Muxer::InitializeTrak(const StreamInfo* info, Track* trak) {
int64_t now = IsoTimeNow();
trak->header.creation_time = now;
trak->header.modification_time = now;
trak->header.duration = 0;
trak->media.header.creation_time = now;
trak->media.header.modification_time = now;
trak->media.header.timescale = info->time_scale();
trak->media.header.duration = 0;
if (!info->language().empty()) {
// Strip off the subtag, if any.
std::string main_language = info->language();
size_t dash = main_language.find('-');
if (dash != std::string::npos) {
main_language.erase(dash);
}
// ISO-639-2/T main language code should be 3 characters.
if (main_language.size() != 3) {
LOG(WARNING) << "'" << main_language << "' is not a valid ISO-639-2 "
<< "language code, ignoring.";
} else {
trak->media.header.language.code = main_language;
}
}
}
bool MP4Muxer::GenerateVideoTrak(const VideoStreamInfo* video_info,
Track* trak,
uint32_t track_id) {
InitializeTrak(video_info, trak);
// width and height specify the track's visual presentation size as
// fixed-point 16.16 values.
uint32_t pixel_width = video_info->pixel_width();
uint32_t pixel_height = video_info->pixel_height();
if (pixel_width == 0 || pixel_height == 0) {
LOG(WARNING) << "pixel width/height are not set. Assuming 1:1.";
pixel_width = 1;
pixel_height = 1;
}
const double sample_aspect_ratio =
static_cast<double>(pixel_width) / pixel_height;
trak->header.width = video_info->width() * sample_aspect_ratio * 0x10000;
trak->header.height = video_info->height() * 0x10000;
VideoSampleEntry video;
video.format =
CodecToFourCC(video_info->codec(), video_info->h26x_stream_format());
video.width = video_info->width();
video.height = video_info->height();
video.codec_configuration.data = video_info->codec_config();
if (pixel_width != 1 || pixel_height != 1) {
video.pixel_aspect.h_spacing = pixel_width;
video.pixel_aspect.v_spacing = pixel_height;
}
SampleDescription& sample_description =
trak->media.information.sample_table.description;
sample_description.type = kVideo;
sample_description.video_entries.push_back(video);
if (video_info->is_encrypted()) {
if (video_info->has_clear_lead()) {
// Add a second entry for clear content.
sample_description.video_entries.push_back(video);
}
// Convert the first entry to an encrypted entry.
VideoSampleEntry& entry = sample_description.video_entries[0];
GenerateSinf(entry.format, video_info->encryption_config(), &entry.sinf);
entry.format = FOURCC_encv;
}
return true;
}
bool MP4Muxer::GenerateAudioTrak(const AudioStreamInfo* audio_info,
Track* trak,
uint32_t track_id) {
InitializeTrak(audio_info, trak);
trak->header.volume = 0x100;
AudioSampleEntry audio;
audio.format =
CodecToFourCC(audio_info->codec(), H26xStreamFormat::kUnSpecified);
switch(audio_info->codec()){
case kCodecAAC:
audio.esds.es_descriptor.set_object_type(
ObjectType::kISO_14496_3); // MPEG4 AAC.
audio.esds.es_descriptor.set_esid(track_id);
audio.esds.es_descriptor.set_decoder_specific_info(
audio_info->codec_config());
audio.esds.es_descriptor.set_max_bitrate(audio_info->max_bitrate());
audio.esds.es_descriptor.set_avg_bitrate(audio_info->avg_bitrate());
break;
case kCodecDTSC:
case kCodecDTSH:
case kCodecDTSL:
case kCodecDTSE:
case kCodecDTSM:
audio.ddts.extra_data = audio_info->codec_config();
audio.ddts.max_bitrate = audio_info->max_bitrate();
audio.ddts.avg_bitrate = audio_info->avg_bitrate();
audio.ddts.sampling_frequency = audio_info->sampling_frequency();
audio.ddts.pcm_sample_depth = audio_info->sample_bits();
break;
case kCodecAC3:
audio.dac3.data = audio_info->codec_config();
break;
case kCodecEAC3:
audio.dec3.data = audio_info->codec_config();
break;
case kCodecFlac:
audio.dfla.data = audio_info->codec_config();
break;
case kCodecOpus:
audio.dops.opus_identification_header = audio_info->codec_config();
break;
default:
NOTIMPLEMENTED() << " Unsupported audio codec " << audio_info->codec();
return false;
}
if (audio_info->codec() == kCodecAC3 || audio_info->codec() == kCodecEAC3) {
// AC3 and EC3 does not fill in actual channel count and sample size in
// sample description entry. Instead, two constants are used.
audio.channelcount = 2;
audio.samplesize = 16;
} else {
audio.channelcount = audio_info->num_channels();
audio.samplesize = audio_info->sample_bits();
}
audio.samplerate = audio_info->sampling_frequency();
SampleTable& sample_table = trak->media.information.sample_table;
SampleDescription& sample_description = sample_table.description;
sample_description.type = kAudio;
sample_description.audio_entries.push_back(audio);
if (audio_info->is_encrypted()) {
if (audio_info->has_clear_lead()) {
// Add a second entry for clear content.
sample_description.audio_entries.push_back(audio);
}
// Convert the first entry to an encrypted entry.
AudioSampleEntry& entry = sample_description.audio_entries[0];
GenerateSinf(entry.format, audio_info->encryption_config(), &entry.sinf);
entry.format = FOURCC_enca;
}
if (audio_info->seek_preroll_ns() > 0) {
sample_table.sample_group_descriptions.resize(1);
SampleGroupDescription& sample_group_description =
sample_table.sample_group_descriptions.back();
sample_group_description.grouping_type = FOURCC_roll;
sample_group_description.audio_roll_recovery_entries.resize(1);
sample_group_description.audio_roll_recovery_entries[0].roll_distance =
GetRollDistance(audio_info->seek_preroll_ns(), audio.samplerate);
// sample to group box is not allowed in the init segment per CMAF
// specification. It is put in the fragment instead.
}
return true;
}
bool MP4Muxer::GenerateTextTrak(const TextStreamInfo* text_info,
Track* trak,
uint32_t track_id) {
InitializeTrak(text_info, trak);
if (text_info->codec_string() == "wvtt") {
// Handle WebVTT.
TextSampleEntry webvtt;
webvtt.format = FOURCC_wvtt;
// 14496-30:2014 7.5 Web Video Text Tracks Sample entry format.
// In the sample entry, a WebVTT configuration box must occur, carrying
// exactly the lines of the WebVTT file header, i.e. all text lines up to
// but excluding the 'two or more line terminators' that end the header.
webvtt.config.config = "WEBVTT";
// The spec does not define a way to carry STYLE and REGION information in
// the mp4 container.
if (!text_info->codec_config().empty()) {
LOG(INFO) << "Skipping possible style / region configuration as the spec "
"does not define a way to carry them inside ISO-BMFF files.";
}
// TODO(rkuroiwa): This should be the source file URI(s). Putting bogus
// string for now so that the box will be there for samples with overlapping
// cues.
webvtt.label.source_label = "source_label";
SampleDescription& sample_description =
trak->media.information.sample_table.description;
sample_description.type = kText;
sample_description.text_entries.push_back(webvtt);
return true;
}
NOTIMPLEMENTED() << text_info->codec_string()
<< " handling not implemented yet.";
return false;
}
base::Optional<Range> MP4Muxer::GetInitRangeStartAndEnd() {
size_t range_offset = 0;
size_t range_size = 0;
const bool has_range = segmenter_->GetInitRange(&range_offset, &range_size);
if (!has_range)
return base::nullopt;
Range range;
SetStartAndEndFromOffsetAndSize(range_offset, range_size, &range);
return range;
}
base::Optional<Range> MP4Muxer::GetIndexRangeStartAndEnd() {
size_t range_offset = 0;
size_t range_size = 0;
const bool has_range = segmenter_->GetIndexRange(&range_offset, &range_size);
if (!has_range)
return base::nullopt;
Range range;
SetStartAndEndFromOffsetAndSize(range_offset, range_size, &range);
return range;
}
void MP4Muxer::FireOnMediaStartEvent() {
if (!muxer_listener())
return;
if (streams().size() > 1) {
LOG(ERROR) << "MuxerListener cannot take more than 1 stream.";
return;
}
DCHECK(!streams().empty()) << "Media started without a stream.";
const uint32_t timescale = segmenter_->GetReferenceTimeScale();
muxer_listener()->OnMediaStart(options(), *streams().front(), timescale,
MuxerListener::kContainerMp4);
}
void MP4Muxer::FireOnMediaEndEvent() {
if (!muxer_listener())
return;
MuxerListener::MediaRanges media_range;
media_range.init_range = GetInitRangeStartAndEnd();
media_range.index_range = GetIndexRangeStartAndEnd();
media_range.subsegment_ranges = segmenter_->GetSegmentRanges();
const float duration_seconds = static_cast<float>(segmenter_->GetDuration());
muxer_listener()->OnMediaEnd(media_range, duration_seconds);
}
uint64_t MP4Muxer::IsoTimeNow() {
// Time in seconds from Jan. 1, 1904 to epoch time, i.e. Jan. 1, 1970.
const uint64_t kIsomTimeOffset = 2082844800l;
return kIsomTimeOffset +
(clock() ? clock()->Now() : base::Time::Now()).ToDoubleT();
}
} // namespace mp4
} // namespace media
} // namespace shaka
Reference in New Issue View Git Blame Copy Permalink