694 lines
26 KiB
C++
694 lines
26 KiB
C++
// Copyright 2014 Google LLC. All rights reserved.
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//
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file or at
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// https://developers.google.com/open-source/licenses/bsd
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#include "packager/media/formats/mp4/mp4_muxer.h"
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#include <algorithm>
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#include "packager/base/strings/string_number_conversions.h"
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#include "packager/base/time/clock.h"
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#include "packager/base/time/time.h"
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#include "packager/file/file.h"
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#include "packager/media/base/aes_encryptor.h"
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#include "packager/media/base/audio_stream_info.h"
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#include "packager/media/base/fourccs.h"
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#include "packager/media/base/key_source.h"
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#include "packager/media/base/media_sample.h"
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#include "packager/media/base/text_stream_info.h"
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#include "packager/media/base/video_stream_info.h"
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#include "packager/media/codecs/es_descriptor.h"
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#include "packager/media/event/muxer_listener.h"
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#include "packager/media/formats/mp4/box_definitions.h"
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#include "packager/media/formats/mp4/low_latency_segment_segmenter.h"
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#include "packager/media/formats/mp4/multi_segment_segmenter.h"
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#include "packager/media/formats/mp4/single_segment_segmenter.h"
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#include "packager/media/formats/ttml/ttml_generator.h"
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#include "packager/status_macros.h"
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namespace shaka {
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namespace media {
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namespace mp4 {
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namespace {
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// Sets the range start and end value from offset and size.
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// |start| and |end| are for byte-range-spec specified in RFC2616.
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void SetStartAndEndFromOffsetAndSize(size_t offset,
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size_t size,
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Range* range) {
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DCHECK(range);
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range->start = static_cast<uint32_t>(offset);
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// Note that ranges are inclusive. So we need - 1.
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range->end = range->start + static_cast<uint32_t>(size) - 1;
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}
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FourCC CodecToFourCC(Codec codec, H26xStreamFormat h26x_stream_format) {
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switch (codec) {
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case kCodecAV1:
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return FOURCC_av01;
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case kCodecH264:
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return h26x_stream_format ==
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H26xStreamFormat::kNalUnitStreamWithParameterSetNalus
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? FOURCC_avc3
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: FOURCC_avc1;
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case kCodecH265:
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return h26x_stream_format ==
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H26xStreamFormat::kNalUnitStreamWithParameterSetNalus
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? FOURCC_hev1
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: FOURCC_hvc1;
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case kCodecH265DolbyVision:
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return h26x_stream_format ==
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H26xStreamFormat::kNalUnitStreamWithParameterSetNalus
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? FOURCC_dvhe
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: FOURCC_dvh1;
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case kCodecVP8:
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return FOURCC_vp08;
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case kCodecVP9:
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return FOURCC_vp09;
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case kCodecAAC:
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case kCodecMP3:
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return FOURCC_mp4a;
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case kCodecAC3:
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return FOURCC_ac_3;
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case kCodecDTSC:
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return FOURCC_dtsc;
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case kCodecDTSH:
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return FOURCC_dtsh;
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case kCodecDTSL:
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return FOURCC_dtsl;
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case kCodecDTSE:
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return FOURCC_dtse;
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case kCodecDTSM:
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return FOURCC_dtsm;
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case kCodecEAC3:
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return FOURCC_ec_3;
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case kCodecAC4:
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return FOURCC_ac_4;
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case kCodecFlac:
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return FOURCC_fLaC;
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case kCodecOpus:
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return FOURCC_Opus;
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case kCodecMha1:
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return FOURCC_mha1;
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case kCodecMhm1:
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return FOURCC_mhm1;
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default:
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return FOURCC_NULL;
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}
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}
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void GenerateSinf(FourCC old_type,
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const EncryptionConfig& encryption_config,
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ProtectionSchemeInfo* sinf) {
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sinf->format.format = old_type;
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DCHECK_NE(encryption_config.protection_scheme, FOURCC_NULL);
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sinf->type.type = encryption_config.protection_scheme;
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// The version of cenc implemented here. CENC 4.
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const int kCencSchemeVersion = 0x00010000;
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sinf->type.version = kCencSchemeVersion;
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auto& track_encryption = sinf->info.track_encryption;
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track_encryption.default_is_protected = 1;
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track_encryption.default_crypt_byte_block =
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encryption_config.crypt_byte_block;
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track_encryption.default_skip_byte_block = encryption_config.skip_byte_block;
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switch (encryption_config.protection_scheme) {
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case FOURCC_cenc:
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case FOURCC_cbc1:
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DCHECK_EQ(track_encryption.default_crypt_byte_block, 0u);
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DCHECK_EQ(track_encryption.default_skip_byte_block, 0u);
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// CENCv3 10.1 ‘cenc’ AES-CTR scheme and 10.2 ‘cbc1’ AES-CBC scheme:
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// The version of the Track Encryption Box (‘tenc’) SHALL be 0.
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track_encryption.version = 0;
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break;
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case FOURCC_cbcs:
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case FOURCC_cens:
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// CENCv3 10.3 ‘cens’ AES-CTR subsample pattern encryption scheme and
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// 10.4 ‘cbcs’ AES-CBC subsample pattern encryption scheme:
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// The version of the Track Encryption Box (‘tenc’) SHALL be 1.
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track_encryption.version = 1;
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break;
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default:
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NOTREACHED() << "Unexpected protection scheme "
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<< encryption_config.protection_scheme;
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}
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track_encryption.default_per_sample_iv_size =
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encryption_config.per_sample_iv_size;
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track_encryption.default_constant_iv = encryption_config.constant_iv;
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track_encryption.default_kid = encryption_config.key_id;
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}
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// The roll distance is expressed in sample units and always takes negative
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// values.
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int16_t GetRollDistance(uint64_t seek_preroll_ns, uint32_t sampling_frequency) {
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const double kNanosecondsPerSecond = 1000000000;
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const double preroll_in_samples =
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seek_preroll_ns / kNanosecondsPerSecond * sampling_frequency;
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// Round to closest integer.
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return -static_cast<int16_t>(preroll_in_samples + 0.5);
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}
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} // namespace
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MP4Muxer::MP4Muxer(const MuxerOptions& options) : Muxer(options) {}
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MP4Muxer::~MP4Muxer() {}
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Status MP4Muxer::InitializeMuxer() {
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// Muxer will be delay-initialized after seeing the first sample.
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to_be_initialized_ = true;
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return Status::OK;
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}
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Status MP4Muxer::Finalize() {
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// This happens on streams that are not initialized, i.e. not going through
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// DelayInitializeMuxer, which can only happen if there are no samples from
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// the stream.
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if (!segmenter_) {
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DCHECK(to_be_initialized_);
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LOG(INFO) << "Skip stream '" << options().output_file_name
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<< "' which does not contain any sample.";
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return Status::OK;
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}
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Status segmenter_finalized = segmenter_->Finalize();
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if (!segmenter_finalized.ok())
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return segmenter_finalized;
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FireOnMediaEndEvent();
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LOG(INFO) << "MP4 file '" << options().output_file_name << "' finalized.";
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return Status::OK;
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}
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Status MP4Muxer::AddMediaSample(size_t stream_id, const MediaSample& sample) {
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if (to_be_initialized_) {
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RETURN_IF_ERROR(UpdateEditListOffsetFromSample(sample));
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RETURN_IF_ERROR(DelayInitializeMuxer());
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to_be_initialized_ = false;
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}
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DCHECK(segmenter_);
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return segmenter_->AddSample(stream_id, sample);
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}
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Status MP4Muxer::FinalizeSegment(size_t stream_id,
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const SegmentInfo& segment_info) {
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DCHECK(segmenter_);
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VLOG(3) << "Finalizing " << (segment_info.is_subsegment ? "sub" : "")
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<< "segment " << segment_info.start_timestamp << " duration "
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<< segment_info.duration;
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return segmenter_->FinalizeSegment(stream_id, segment_info);
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}
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Status MP4Muxer::DelayInitializeMuxer() {
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DCHECK(!streams().empty());
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std::unique_ptr<FileType> ftyp(new FileType);
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std::unique_ptr<Movie> moov(new Movie);
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ftyp->major_brand = FOURCC_mp41;
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ftyp->compatible_brands.push_back(FOURCC_iso8);
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ftyp->compatible_brands.push_back(FOURCC_isom);
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ftyp->compatible_brands.push_back(FOURCC_mp41);
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ftyp->compatible_brands.push_back(FOURCC_dash);
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if (streams().size() == 1) {
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FourCC codec_fourcc = FOURCC_NULL;
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if (streams()[0]->stream_type() == kStreamVideo) {
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codec_fourcc =
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CodecToFourCC(streams()[0]->codec(),
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static_cast<const VideoStreamInfo*>(streams()[0].get())
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->h26x_stream_format());
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if (codec_fourcc != FOURCC_NULL)
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ftyp->compatible_brands.push_back(codec_fourcc);
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// https://professional.dolby.com/siteassets/content-creation/dolby-vision-for-content-creators/dolby_vision_bitstreams_within_the_iso_base_media_file_format_dec2017.pdf
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if (streams()[0].get()->codec_string().find("dvh") != std::string::npos)
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ftyp->compatible_brands.push_back(FOURCC_dby1);
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}
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// CMAF allows only one track/stream per file.
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// CMAF requires single initialization switching for AVC3/HEV1, which is not
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// supported yet.
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if (codec_fourcc != FOURCC_avc3 && codec_fourcc != FOURCC_hev1)
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ftyp->compatible_brands.push_back(FOURCC_cmfc);
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}
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moov->header.creation_time = IsoTimeNow();
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moov->header.modification_time = IsoTimeNow();
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moov->header.next_track_id = static_cast<uint32_t>(streams().size()) + 1;
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moov->tracks.resize(streams().size());
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moov->extends.tracks.resize(streams().size());
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// Initialize tracks.
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for (uint32_t i = 0; i < streams().size(); ++i) {
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const StreamInfo* stream = streams()[i].get();
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Track& trak = moov->tracks[i];
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trak.header.track_id = i + 1;
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TrackExtends& trex = moov->extends.tracks[i];
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trex.track_id = trak.header.track_id;
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trex.default_sample_description_index = 1;
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bool generate_trak_result = false;
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switch (stream->stream_type()) {
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case kStreamVideo:
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generate_trak_result = GenerateVideoTrak(
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static_cast<const VideoStreamInfo*>(stream), &trak);
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break;
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case kStreamAudio:
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generate_trak_result = GenerateAudioTrak(
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static_cast<const AudioStreamInfo*>(stream), &trak);
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break;
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case kStreamText:
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generate_trak_result = GenerateTextTrak(
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static_cast<const TextStreamInfo*>(stream), &trak);
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break;
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default:
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NOTIMPLEMENTED() << "Not implemented for stream type: "
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<< stream->stream_type();
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}
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if (!generate_trak_result)
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return Status(error::MUXER_FAILURE, "Failed to generate trak.");
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// Generate EditList if needed. See UpdateEditListOffsetFromSample() for
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// more information.
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if (edit_list_offset_.value() > 0) {
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EditListEntry entry;
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entry.media_time = edit_list_offset_.value();
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entry.media_rate_integer = 1;
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trak.edit.list.edits.push_back(entry);
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}
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if (stream->is_encrypted() && options().mp4_params.include_pssh_in_stream) {
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moov->pssh.clear();
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const auto& key_system_info = stream->encryption_config().key_system_info;
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for (const ProtectionSystemSpecificInfo& system : key_system_info) {
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if (system.psshs.empty())
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continue;
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ProtectionSystemSpecificHeader pssh;
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pssh.raw_box = system.psshs;
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moov->pssh.push_back(pssh);
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}
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}
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}
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if (options().segment_template.empty()) {
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segmenter_.reset(new SingleSegmentSegmenter(options(), std::move(ftyp),
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std::move(moov)));
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} else if (options().mp4_params.low_latency_dash_mode) {
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segmenter_.reset(new LowLatencySegmentSegmenter(options(), std::move(ftyp),
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std::move(moov)));
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} else {
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segmenter_.reset(
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new MultiSegmentSegmenter(options(), std::move(ftyp), std::move(moov)));
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}
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const Status segmenter_initialized =
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segmenter_->Initialize(streams(), muxer_listener(), progress_listener());
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if (!segmenter_initialized.ok())
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return segmenter_initialized;
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FireOnMediaStartEvent();
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return Status::OK;
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}
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Status MP4Muxer::UpdateEditListOffsetFromSample(const MediaSample& sample) {
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if (edit_list_offset_)
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return Status::OK;
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const int64_t pts = sample.pts();
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const int64_t dts = sample.dts();
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// An EditList entry is inserted if one of the below conditions occur [4]:
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// (1) pts > dts for the first sample. Due to Chrome's dts bug [1], dts is
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// used in buffered range API, while pts is used elsewhere (players,
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// manifests, and Chrome's own appendWindow check etc.), this
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// inconsistency creates various problems, including possible stalls
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// during playback. Since Chrome adjusts pts only when seeing EditList
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// [2], we can insert an EditList with the time equal to difference of pts
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// and dts to make aligned buffered ranges using pts and dts. This
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// effectively workarounds the dts bug. It is also recommended by ISO-BMFF
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// specification [3].
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// (2) pts == dts and with pts < 0. This happens for some audio codecs where a
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// negative presentation timestamp signals that the sample is not supposed
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// to be shown, i.e. for audio priming. EditList is needed to encode
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// negative timestamps.
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// [1] https://crbug.com/718641, fixed but behind MseBufferByPts, still not
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// enabled as of M67.
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// [2] This is actually a bug, see https://crbug.com/354518. It looks like
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// Chrome is planning to enable the fix for [1] before addressing this
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// bug, so we are safe.
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// [3] ISO 14496-12:2015 8.6.6.1
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// It is recommended that such an edit be used to establish a presentation
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// time of 0 for the first presented sample, when composition offsets are
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// used.
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// [4] ISO 23009-19:2018 7.5.13
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// In two cases, an EditBox containing a single EditListBox with the
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// following constraints may be present in the CMAF header of a CMAF track
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// to adjust the presentation time of all media samples in the CMAF track.
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// a) The first case is a video CMAF track file using v0 TrackRunBoxes
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// with positive composition offsets to reorder video media samples.
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// b) The second case is an audio CMAF track where each media sample's
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// presentation time does not equal its composition time.
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const int64_t pts_dts_offset = pts - dts;
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if (pts_dts_offset > 0) {
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if (pts < 0) {
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LOG(ERROR) << "Negative presentation timestamp (" << pts
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<< ") is not supported when there is an offset between "
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"presentation timestamp and decoding timestamp ("
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<< dts << ").";
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return Status(error::MUXER_FAILURE,
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"Unsupported negative pts when there is an offset between "
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"pts and dts.");
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}
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edit_list_offset_ = pts_dts_offset;
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return Status::OK;
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}
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if (pts_dts_offset < 0) {
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LOG(ERROR) << "presentation timestamp (" << pts
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<< ") is not supposed to be greater than decoding timestamp ("
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<< dts << ").";
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return Status(error::MUXER_FAILURE, "Not expecting pts < dts.");
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}
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edit_list_offset_ = std::max(-sample.pts(), static_cast<int64_t>(0));
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return Status::OK;
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}
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void MP4Muxer::InitializeTrak(const StreamInfo* info, Track* trak) {
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int64_t now = IsoTimeNow();
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trak->header.creation_time = now;
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trak->header.modification_time = now;
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trak->header.duration = 0;
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trak->media.header.creation_time = now;
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trak->media.header.modification_time = now;
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trak->media.header.timescale = info->time_scale();
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trak->media.header.duration = 0;
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if (!info->language().empty()) {
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// Strip off the subtag, if any.
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std::string main_language = info->language();
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size_t dash = main_language.find('-');
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if (dash != std::string::npos) {
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main_language.erase(dash);
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}
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// ISO-639-2/T main language code should be 3 characters.
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if (main_language.size() != 3) {
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LOG(WARNING) << "'" << main_language << "' is not a valid ISO-639-2 "
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<< "language code, ignoring.";
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} else {
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trak->media.header.language.code = main_language;
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}
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}
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}
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bool MP4Muxer::GenerateVideoTrak(const VideoStreamInfo* video_info,
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Track* trak) {
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InitializeTrak(video_info, trak);
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// width and height specify the track's visual presentation size as
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// fixed-point 16.16 values.
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uint32_t pixel_width = video_info->pixel_width();
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uint32_t pixel_height = video_info->pixel_height();
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if (pixel_width == 0 || pixel_height == 0) {
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LOG(WARNING) << "pixel width/height are not set. Assuming 1:1.";
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pixel_width = 1;
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pixel_height = 1;
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}
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const double sample_aspect_ratio =
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static_cast<double>(pixel_width) / pixel_height;
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trak->header.width = video_info->width() * sample_aspect_ratio * 0x10000;
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trak->header.height = video_info->height() * 0x10000;
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VideoSampleEntry video;
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video.format =
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CodecToFourCC(video_info->codec(), video_info->h26x_stream_format());
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video.width = video_info->width();
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video.height = video_info->height();
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video.codec_configuration.data = video_info->codec_config();
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if (!video.ParseExtraCodecConfigsVector(video_info->extra_config())) {
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LOG(ERROR) << "Malformed extra codec configs: "
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<< base::HexEncode(video_info->extra_config().data(),
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video_info->extra_config().size());
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return false;
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}
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if (pixel_width != 1 || pixel_height != 1) {
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video.pixel_aspect.h_spacing = pixel_width;
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video.pixel_aspect.v_spacing = pixel_height;
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}
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SampleDescription& sample_description =
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trak->media.information.sample_table.description;
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sample_description.type = kVideo;
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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) {
|
||
InitializeTrak(audio_info, trak);
|
||
|
||
trak->header.volume = 0x100;
|
||
|
||
AudioSampleEntry audio;
|
||
audio.format =
|
||
CodecToFourCC(audio_info->codec(), H26xStreamFormat::kUnSpecified);
|
||
switch(audio_info->codec()){
|
||
case kCodecAAC: {
|
||
DecoderConfigDescriptor* decoder_config =
|
||
audio.esds.es_descriptor.mutable_decoder_config_descriptor();
|
||
decoder_config->set_object_type(ObjectType::kISO_14496_3); // MPEG4 AAC.
|
||
decoder_config->set_max_bitrate(audio_info->max_bitrate());
|
||
decoder_config->set_avg_bitrate(audio_info->avg_bitrate());
|
||
decoder_config->mutable_decoder_specific_info_descriptor()->set_data(
|
||
audio_info->codec_config());
|
||
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 kCodecAC4:
|
||
audio.dac4.data = audio_info->codec_config();
|
||
break;
|
||
case kCodecFlac:
|
||
audio.dfla.data = audio_info->codec_config();
|
||
break;
|
||
case kCodecMP3: {
|
||
DecoderConfigDescriptor* decoder_config =
|
||
audio.esds.es_descriptor.mutable_decoder_config_descriptor();
|
||
uint32_t samplerate = audio_info->sampling_frequency();
|
||
if (samplerate < 32000)
|
||
decoder_config->set_object_type(ObjectType::kISO_13818_3_MPEG1);
|
||
else
|
||
decoder_config->set_object_type(ObjectType::kISO_11172_3_MPEG1);
|
||
decoder_config->set_max_bitrate(audio_info->max_bitrate());
|
||
decoder_config->set_avg_bitrate(audio_info->avg_bitrate());
|
||
|
||
// For values of DecoderConfigDescriptor.objectTypeIndication
|
||
// that refer to streams complying with ISO/IEC 11172-3 or
|
||
// ISO/IEC 13818-3 the decoder specific information is empty
|
||
// since all necessary data is contained in the bitstream frames
|
||
// itself.
|
||
break;
|
||
}
|
||
case kCodecOpus:
|
||
audio.dops.opus_identification_header = audio_info->codec_config();
|
||
break;
|
||
case kCodecMha1:
|
||
case kCodecMhm1:
|
||
audio.mhac.data = 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 if (audio_info->codec() == kCodecAC4) {
|
||
//ETSI TS 103 190-2, E.4.5 channelcount should be set to the total number of
|
||
//audio outputchannels of the default audio presentation of that track
|
||
audio.channelcount = audio_info->num_channels();
|
||
//ETSI TS 103 190-2, E.4.6 samplesize shall be set to 16.
|
||
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) {
|
||
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->regions().empty() || !text_info->css_styles().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;
|
||
} else if (text_info->codec_string() == "ttml") {
|
||
// Handle TTML.
|
||
TextSampleEntry ttml;
|
||
ttml.format = FOURCC_stpp;
|
||
ttml.namespace_ = ttml::TtmlGenerator::kTtNamespace;
|
||
|
||
SampleDescription& sample_description =
|
||
trak->media.information.sample_table.description;
|
||
sample_description.type = kSubtitle;
|
||
sample_description.text_entries.push_back(ttml);
|
||
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 int32_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
|