blob: be31709b05017603df7c655e6e06e417eaef997e [file] [log] [blame]
// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "media/filters/ffmpeg_demuxer.h"
#include <algorithm>
#include <string>
#include "base/base64.h"
#include "base/bind.h"
#include "base/callback.h"
#include "base/callback_helpers.h"
#include "base/memory/scoped_ptr.h"
#include "base/message_loop/message_loop_proxy.h"
#include "base/metrics/sparse_histogram.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/string_util.h"
#include "base/strings/stringprintf.h"
#include "base/sys_byteorder.h"
#include "base/task_runner_util.h"
#include "base/time/time.h"
#include "media/base/audio_decoder_config.h"
#include "media/base/bind_to_current_loop.h"
#include "media/base/decoder_buffer.h"
#include "media/base/decrypt_config.h"
#include "media/base/limits.h"
#include "media/base/media_log.h"
#include "media/base/video_decoder_config.h"
#include "media/ffmpeg/ffmpeg_common.h"
#include "media/filters/ffmpeg_aac_bitstream_converter.h"
#include "media/filters/ffmpeg_bitstream_converter.h"
#include "media/filters/ffmpeg_glue.h"
#include "media/filters/ffmpeg_h264_to_annex_b_bitstream_converter.h"
#include "media/filters/webvtt_util.h"
#include "media/formats/webm/webm_crypto_helpers.h"
namespace media {
static base::Time ExtractTimelineOffset(AVFormatContext* format_context) {
if (strstr(format_context->iformat->name, "webm") ||
strstr(format_context->iformat->name, "matroska")) {
const AVDictionaryEntry* entry =
av_dict_get(format_context->metadata, "creation_time", NULL, 0);
base::Time timeline_offset;
if (entry != NULL && entry->value != NULL &&
FFmpegUTCDateToTime(entry->value, &timeline_offset)) {
return timeline_offset;
}
}
return base::Time();
}
static base::TimeDelta FramesToTimeDelta(int frames, double sample_rate) {
return base::TimeDelta::FromMicroseconds(
frames * base::Time::kMicrosecondsPerSecond / sample_rate);
}
static base::TimeDelta ExtractStartTime(AVStream* stream,
base::TimeDelta start_time_estimate) {
DCHECK(start_time_estimate != kNoTimestamp());
if (stream->start_time == static_cast<int64_t>(AV_NOPTS_VALUE)) {
return start_time_estimate == kInfiniteDuration() ? kNoTimestamp()
: start_time_estimate;
}
// First try the lower of the estimate and the |start_time| value.
base::TimeDelta start_time =
std::min(ConvertFromTimeBase(stream->time_base, stream->start_time),
start_time_estimate);
// Next see if the first buffered pts value is usable.
if (stream->pts_buffer[0] != static_cast<int64_t>(AV_NOPTS_VALUE)) {
const base::TimeDelta buffered_pts =
ConvertFromTimeBase(stream->time_base, stream->pts_buffer[0]);
if (buffered_pts < start_time)
start_time = buffered_pts;
}
// NOTE: Do not use AVStream->first_dts since |start_time| should be a
// presentation timestamp.
return start_time;
}
//
// FFmpegDemuxerStream
//
FFmpegDemuxerStream::FFmpegDemuxerStream(FFmpegDemuxer* demuxer,
AVStream* stream)
: demuxer_(demuxer),
task_runner_(base::MessageLoopProxy::current()),
stream_(stream),
type_(UNKNOWN),
liveness_(LIVENESS_UNKNOWN),
end_of_stream_(false),
last_packet_timestamp_(kNoTimestamp()),
last_packet_duration_(kNoTimestamp()),
video_rotation_(VIDEO_ROTATION_0),
fixup_negative_ogg_timestamps_(false) {
DCHECK(demuxer_);
bool is_encrypted = false;
int rotation = 0;
AVDictionaryEntry* rotation_entry = NULL;
// Determine our media format.
switch (stream->codec->codec_type) {
case AVMEDIA_TYPE_AUDIO:
type_ = AUDIO;
AVStreamToAudioDecoderConfig(stream, &audio_config_, true);
is_encrypted = audio_config_.is_encrypted();
break;
case AVMEDIA_TYPE_VIDEO:
type_ = VIDEO;
AVStreamToVideoDecoderConfig(stream, &video_config_, true);
is_encrypted = video_config_.is_encrypted();
rotation_entry = av_dict_get(stream->metadata, "rotate", NULL, 0);
if (rotation_entry && rotation_entry->value && rotation_entry->value[0])
base::StringToInt(rotation_entry->value, &rotation);
switch (rotation) {
case 0:
break;
case 90:
video_rotation_ = VIDEO_ROTATION_90;
break;
case 180:
video_rotation_ = VIDEO_ROTATION_180;
break;
case 270:
video_rotation_ = VIDEO_ROTATION_270;
break;
default:
LOG(ERROR) << "Unsupported video rotation metadata: " << rotation;
break;
}
break;
case AVMEDIA_TYPE_SUBTITLE:
type_ = TEXT;
break;
default:
NOTREACHED();
break;
}
// Calculate the duration.
duration_ = ConvertStreamTimestamp(stream->time_base, stream->duration);
if (is_encrypted) {
AVDictionaryEntry* key = av_dict_get(stream->metadata, "enc_key_id", NULL,
0);
DCHECK(key);
DCHECK(key->value);
if (!key || !key->value)
return;
base::StringPiece base64_key_id(key->value);
std::string enc_key_id;
base::Base64Decode(base64_key_id, &enc_key_id);
DCHECK(!enc_key_id.empty());
if (enc_key_id.empty())
return;
encryption_key_id_.assign(enc_key_id);
demuxer_->OnEncryptedMediaInitData(kWebMInitDataType, enc_key_id);
}
}
FFmpegDemuxerStream::~FFmpegDemuxerStream() {
DCHECK(!demuxer_);
DCHECK(read_cb_.is_null());
DCHECK(buffer_queue_.IsEmpty());
}
void FFmpegDemuxerStream::EnqueuePacket(ScopedAVPacket packet) {
DCHECK(task_runner_->BelongsToCurrentThread());
if (!demuxer_ || end_of_stream_) {
NOTREACHED() << "Attempted to enqueue packet on a stopped stream";
return;
}
#if defined(USE_PROPRIETARY_CODECS)
// Convert the packet if there is a bitstream filter.
if (packet->data && bitstream_converter_ &&
!bitstream_converter_->ConvertPacket(packet.get())) {
LOG(ERROR) << "Format conversion failed.";
}
#endif
// Get side data if any. For now, the only type of side_data is VP8 Alpha. We
// keep this generic so that other side_data types in the future can be
// handled the same way as well.
av_packet_split_side_data(packet.get());
scoped_refptr<DecoderBuffer> buffer;
if (type() == DemuxerStream::TEXT) {
int id_size = 0;
uint8* id_data = av_packet_get_side_data(
packet.get(),
AV_PKT_DATA_WEBVTT_IDENTIFIER,
&id_size);
int settings_size = 0;
uint8* settings_data = av_packet_get_side_data(
packet.get(),
AV_PKT_DATA_WEBVTT_SETTINGS,
&settings_size);
std::vector<uint8> side_data;
MakeSideData(id_data, id_data + id_size,
settings_data, settings_data + settings_size,
&side_data);
buffer = DecoderBuffer::CopyFrom(packet.get()->data, packet.get()->size,
side_data.data(), side_data.size());
} else {
int side_data_size = 0;
uint8* side_data = av_packet_get_side_data(
packet.get(),
AV_PKT_DATA_MATROSKA_BLOCKADDITIONAL,
&side_data_size);
scoped_ptr<DecryptConfig> decrypt_config;
int data_offset = 0;
if ((type() == DemuxerStream::AUDIO && audio_config_.is_encrypted()) ||
(type() == DemuxerStream::VIDEO && video_config_.is_encrypted())) {
if (!WebMCreateDecryptConfig(
packet->data, packet->size,
reinterpret_cast<const uint8*>(encryption_key_id_.data()),
encryption_key_id_.size(),
&decrypt_config,
&data_offset)) {
LOG(ERROR) << "Creation of DecryptConfig failed.";
}
}
// If a packet is returned by FFmpeg's av_parser_parse2() the packet will
// reference inner memory of FFmpeg. As such we should transfer the packet
// into memory we control.
if (side_data_size > 0) {
buffer = DecoderBuffer::CopyFrom(packet.get()->data + data_offset,
packet.get()->size - data_offset,
side_data, side_data_size);
} else {
buffer = DecoderBuffer::CopyFrom(packet.get()->data + data_offset,
packet.get()->size - data_offset);
}
int skip_samples_size = 0;
const uint32* skip_samples_ptr =
reinterpret_cast<const uint32*>(av_packet_get_side_data(
packet.get(), AV_PKT_DATA_SKIP_SAMPLES, &skip_samples_size));
const int kSkipSamplesValidSize = 10;
const int kSkipEndSamplesOffset = 1;
if (skip_samples_size >= kSkipSamplesValidSize) {
// Because FFmpeg rolls codec delay and skip samples into one we can only
// allow front discard padding on the first buffer. Otherwise the discard
// helper can't figure out which data to discard. See AudioDiscardHelper.
int discard_front_samples = base::ByteSwapToLE32(*skip_samples_ptr);
if (last_packet_timestamp_ != kNoTimestamp() && discard_front_samples) {
DLOG(ERROR) << "Skip samples are only allowed for the first packet.";
discard_front_samples = 0;
}
const int discard_end_samples =
base::ByteSwapToLE32(*(skip_samples_ptr + kSkipEndSamplesOffset));
const int samples_per_second =
audio_decoder_config().samples_per_second();
buffer->set_discard_padding(std::make_pair(
FramesToTimeDelta(discard_front_samples, samples_per_second),
FramesToTimeDelta(discard_end_samples, samples_per_second)));
}
if (decrypt_config)
buffer->set_decrypt_config(decrypt_config.Pass());
}
if (packet->duration >= 0) {
buffer->set_duration(
ConvertStreamTimestamp(stream_->time_base, packet->duration));
} else {
// TODO(wolenetz): Remove when FFmpeg stops returning negative durations.
// https://crbug.com/394418
DVLOG(1) << "FFmpeg returned a buffer with a negative duration! "
<< packet->duration;
buffer->set_duration(kNoTimestamp());
}
// Note: If pts is AV_NOPTS_VALUE, stream_timestamp will be kNoTimestamp().
const base::TimeDelta stream_timestamp =
ConvertStreamTimestamp(stream_->time_base, packet->pts);
if (stream_timestamp != kNoTimestamp()) {
const bool is_audio = type() == AUDIO;
// If this is an OGG file with negative timestamps don't rebase any other
// stream types against the negative starting time.
base::TimeDelta start_time = demuxer_->start_time();
if (fixup_negative_ogg_timestamps_ && !is_audio &&
start_time < base::TimeDelta()) {
start_time = base::TimeDelta();
}
// Don't rebase timestamps for positive start times, the HTML Media Spec
// details this in section "4.8.10.6 Offsets into the media resource." We
// will still need to rebase timestamps before seeking with FFmpeg though.
if (start_time > base::TimeDelta())
start_time = base::TimeDelta();
buffer->set_timestamp(stream_timestamp - start_time);
// If enabled, mark audio packets with negative timestamps for post-decode
// discard.
if (fixup_negative_ogg_timestamps_ && is_audio &&
stream_timestamp < base::TimeDelta() &&
buffer->duration() != kNoTimestamp()) {
if (stream_timestamp + buffer->duration() < base::TimeDelta()) {
// Discard the entire packet if it's entirely before zero.
buffer->set_discard_padding(
std::make_pair(kInfiniteDuration(), base::TimeDelta()));
} else {
// Only discard part of the frame if it overlaps zero.
buffer->set_discard_padding(
std::make_pair(-stream_timestamp, base::TimeDelta()));
}
}
} else {
// If this happens on the first packet, decoders will throw an error.
buffer->set_timestamp(kNoTimestamp());
}
if (last_packet_timestamp_ != kNoTimestamp()) {
// FFmpeg doesn't support chained ogg correctly. Instead of guaranteeing
// continuity across links in the chain it uses the timestamp information
// from each link directly. Doing so can lead to timestamps which appear to
// go backwards in time.
//
// If the new link starts with a negative timestamp or a timestamp less than
// the original (positive) |start_time|, we will get a negative timestamp
// here. It's also possible FFmpeg returns kNoTimestamp() here if it's not
// able to work out a timestamp using the previous link and the next.
//
// Fixing chained ogg is non-trivial, so for now just reuse the last good
// timestamp. The decoder will rewrite the timestamps to be sample accurate
// later. See http://crbug.com/396864.
if (fixup_negative_ogg_timestamps_ &&
(buffer->timestamp() == kNoTimestamp() ||
buffer->timestamp() < last_packet_timestamp_)) {
buffer->set_timestamp(last_packet_timestamp_ +
(last_packet_duration_ != kNoTimestamp()
? last_packet_duration_
: base::TimeDelta::FromMicroseconds(1)));
}
// The demuxer should always output positive timestamps.
DCHECK(buffer->timestamp() >= base::TimeDelta());
DCHECK(buffer->timestamp() != kNoTimestamp());
if (last_packet_timestamp_ < buffer->timestamp()) {
buffered_ranges_.Add(last_packet_timestamp_, buffer->timestamp());
demuxer_->NotifyBufferingChanged();
}
}
if (packet.get()->flags & AV_PKT_FLAG_KEY)
buffer->set_is_key_frame(true);
last_packet_timestamp_ = buffer->timestamp();
last_packet_duration_ = buffer->duration();
buffer_queue_.Push(buffer);
SatisfyPendingRead();
}
void FFmpegDemuxerStream::SetEndOfStream() {
DCHECK(task_runner_->BelongsToCurrentThread());
end_of_stream_ = true;
SatisfyPendingRead();
}
void FFmpegDemuxerStream::FlushBuffers() {
DCHECK(task_runner_->BelongsToCurrentThread());
DCHECK(read_cb_.is_null()) << "There should be no pending read";
// H264 and AAC require that we resend the header after flush.
// Reset bitstream for converter to do so.
// This is related to chromium issue 140371 (http://crbug.com/140371).
ResetBitstreamConverter();
buffer_queue_.Clear();
end_of_stream_ = false;
last_packet_timestamp_ = kNoTimestamp();
last_packet_duration_ = kNoTimestamp();
}
void FFmpegDemuxerStream::Stop() {
DCHECK(task_runner_->BelongsToCurrentThread());
buffer_queue_.Clear();
if (!read_cb_.is_null()) {
base::ResetAndReturn(&read_cb_).Run(
DemuxerStream::kOk, DecoderBuffer::CreateEOSBuffer());
}
demuxer_ = NULL;
stream_ = NULL;
end_of_stream_ = true;
}
DemuxerStream::Type FFmpegDemuxerStream::type() const {
DCHECK(task_runner_->BelongsToCurrentThread());
return type_;
}
DemuxerStream::Liveness FFmpegDemuxerStream::liveness() const {
DCHECK(task_runner_->BelongsToCurrentThread());
return liveness_;
}
void FFmpegDemuxerStream::Read(const ReadCB& read_cb) {
DCHECK(task_runner_->BelongsToCurrentThread());
CHECK(read_cb_.is_null()) << "Overlapping reads are not supported";
read_cb_ = BindToCurrentLoop(read_cb);
// Don't accept any additional reads if we've been told to stop.
// The |demuxer_| may have been destroyed in the pipeline thread.
//
// TODO(scherkus): it would be cleaner to reply with an error message.
if (!demuxer_) {
base::ResetAndReturn(&read_cb_).Run(
DemuxerStream::kOk, DecoderBuffer::CreateEOSBuffer());
return;
}
SatisfyPendingRead();
}
void FFmpegDemuxerStream::EnableBitstreamConverter() {
DCHECK(task_runner_->BelongsToCurrentThread());
#if defined(USE_PROPRIETARY_CODECS)
InitBitstreamConverter();
#else
NOTREACHED() << "Proprietary codecs not enabled.";
#endif
}
void FFmpegDemuxerStream::ResetBitstreamConverter() {
#if defined(USE_PROPRIETARY_CODECS)
if (bitstream_converter_)
InitBitstreamConverter();
#endif // defined(USE_PROPRIETARY_CODECS)
}
void FFmpegDemuxerStream::InitBitstreamConverter() {
#if defined(USE_PROPRIETARY_CODECS)
if (stream_->codec->codec_id == AV_CODEC_ID_H264) {
bitstream_converter_.reset(
new FFmpegH264ToAnnexBBitstreamConverter(stream_->codec));
} else if (stream_->codec->codec_id == AV_CODEC_ID_AAC) {
bitstream_converter_.reset(
new FFmpegAACBitstreamConverter(stream_->codec));
}
#endif // defined(USE_PROPRIETARY_CODECS)
}
bool FFmpegDemuxerStream::SupportsConfigChanges() { return false; }
AudioDecoderConfig FFmpegDemuxerStream::audio_decoder_config() {
DCHECK(task_runner_->BelongsToCurrentThread());
CHECK_EQ(type_, AUDIO);
return audio_config_;
}
VideoDecoderConfig FFmpegDemuxerStream::video_decoder_config() {
DCHECK(task_runner_->BelongsToCurrentThread());
CHECK_EQ(type_, VIDEO);
return video_config_;
}
VideoRotation FFmpegDemuxerStream::video_rotation() {
return video_rotation_;
}
void FFmpegDemuxerStream::SetLiveness(Liveness liveness) {
DCHECK(task_runner_->BelongsToCurrentThread());
DCHECK_EQ(liveness_, LIVENESS_UNKNOWN);
liveness_ = liveness;
}
base::TimeDelta FFmpegDemuxerStream::GetElapsedTime() const {
return ConvertStreamTimestamp(stream_->time_base, stream_->cur_dts);
}
Ranges<base::TimeDelta> FFmpegDemuxerStream::GetBufferedRanges() const {
return buffered_ranges_;
}
void FFmpegDemuxerStream::SatisfyPendingRead() {
DCHECK(task_runner_->BelongsToCurrentThread());
if (!read_cb_.is_null()) {
if (!buffer_queue_.IsEmpty()) {
base::ResetAndReturn(&read_cb_).Run(
DemuxerStream::kOk, buffer_queue_.Pop());
} else if (end_of_stream_) {
base::ResetAndReturn(&read_cb_).Run(
DemuxerStream::kOk, DecoderBuffer::CreateEOSBuffer());
}
}
// Have capacity? Ask for more!
if (HasAvailableCapacity() && !end_of_stream_) {
demuxer_->NotifyCapacityAvailable();
}
}
bool FFmpegDemuxerStream::HasAvailableCapacity() {
// TODO(scherkus): Remove this return and reenable time-based capacity
// after our data sources support canceling/concurrent reads, see
// http://crbug.com/165762 for details.
#if 1
return !read_cb_.is_null();
#else
// Try to have one second's worth of encoded data per stream.
const base::TimeDelta kCapacity = base::TimeDelta::FromSeconds(1);
return buffer_queue_.IsEmpty() || buffer_queue_.Duration() < kCapacity;
#endif
}
size_t FFmpegDemuxerStream::MemoryUsage() const {
return buffer_queue_.data_size();
}
TextKind FFmpegDemuxerStream::GetTextKind() const {
DCHECK_EQ(type_, DemuxerStream::TEXT);
if (stream_->disposition & AV_DISPOSITION_CAPTIONS)
return kTextCaptions;
if (stream_->disposition & AV_DISPOSITION_DESCRIPTIONS)
return kTextDescriptions;
if (stream_->disposition & AV_DISPOSITION_METADATA)
return kTextMetadata;
return kTextSubtitles;
}
std::string FFmpegDemuxerStream::GetMetadata(const char* key) const {
const AVDictionaryEntry* entry =
av_dict_get(stream_->metadata, key, NULL, 0);
return (entry == NULL || entry->value == NULL) ? "" : entry->value;
}
// static
base::TimeDelta FFmpegDemuxerStream::ConvertStreamTimestamp(
const AVRational& time_base, int64 timestamp) {
if (timestamp == static_cast<int64>(AV_NOPTS_VALUE))
return kNoTimestamp();
return ConvertFromTimeBase(time_base, timestamp);
}
//
// FFmpegDemuxer
//
FFmpegDemuxer::FFmpegDemuxer(
const scoped_refptr<base::SingleThreadTaskRunner>& task_runner,
DataSource* data_source,
const EncryptedMediaInitDataCB& encrypted_media_init_data_cb,
const scoped_refptr<MediaLog>& media_log)
: host_(NULL),
task_runner_(task_runner),
blocking_thread_("FFmpegDemuxer"),
pending_read_(false),
pending_seek_(false),
data_source_(data_source),
media_log_(media_log),
bitrate_(0),
start_time_(kNoTimestamp()),
preferred_stream_for_seeking_(-1, kNoTimestamp()),
fallback_stream_for_seeking_(-1, kNoTimestamp()),
text_enabled_(false),
duration_known_(false),
encrypted_media_init_data_cb_(encrypted_media_init_data_cb),
weak_factory_(this) {
DCHECK(task_runner_.get());
DCHECK(data_source_);
}
FFmpegDemuxer::~FFmpegDemuxer() {}
void FFmpegDemuxer::Stop() {
DCHECK(task_runner_->BelongsToCurrentThread());
// The order of Stop() and Abort() is important here. If Abort() is called
// first, control may pass into FFmpeg where it can destruct buffers that are
// in the process of being fulfilled by the DataSource.
data_source_->Stop();
url_protocol_->Abort();
// This will block until all tasks complete. Note that after this returns it's
// possible for reply tasks (e.g., OnReadFrameDone()) to be queued on this
// thread. Each of the reply task methods must check whether we've stopped the
// thread and drop their results on the floor.
blocking_thread_.Stop();
StreamVector::iterator iter;
for (iter = streams_.begin(); iter != streams_.end(); ++iter) {
if (*iter)
(*iter)->Stop();
}
data_source_ = NULL;
}
void FFmpegDemuxer::Seek(base::TimeDelta time, const PipelineStatusCB& cb) {
DCHECK(task_runner_->BelongsToCurrentThread());
CHECK(!pending_seek_);
// TODO(scherkus): Inspect |pending_read_| and cancel IO via |blocking_url_|,
// otherwise we can end up waiting for a pre-seek read to complete even though
// we know we're going to drop it on the floor.
// FFmpeg requires seeks to be adjusted according to the lowest starting time.
// Since EnqueuePacket() rebased negative timestamps by the start time, we
// must correct the shift here.
//
// Additionally, to workaround limitations in how we expose seekable ranges to
// Blink (http://crbug.com/137275), we also want to clamp seeks before the
// start time to the start time.
const base::TimeDelta seek_time =
start_time_ < base::TimeDelta() ? time + start_time_
: time < start_time_ ? start_time_ : time;
// Choose the seeking stream based on whether it contains the seek time, if no
// match can be found prefer the preferred stream.
//
// TODO(dalecurtis): Currently FFmpeg does not ensure that all streams in a
// given container will demux all packets after the seek point. Instead it
// only guarantees that all packets after the file position of the seek will
// be demuxed. It's an open question whether FFmpeg should fix this:
// http://lists.ffmpeg.org/pipermail/ffmpeg-devel/2014-June/159212.html
// Tracked by http://crbug.com/387996.
DCHECK(preferred_stream_for_seeking_.second != kNoTimestamp());
const int stream_index =
seek_time < preferred_stream_for_seeking_.second &&
seek_time >= fallback_stream_for_seeking_.second
? fallback_stream_for_seeking_.first
: preferred_stream_for_seeking_.first;
DCHECK_NE(stream_index, -1);
const AVStream* seeking_stream =
glue_->format_context()->streams[stream_index];
pending_seek_ = true;
base::PostTaskAndReplyWithResult(
blocking_thread_.message_loop_proxy().get(),
FROM_HERE,
base::Bind(&av_seek_frame,
glue_->format_context(),
seeking_stream->index,
ConvertToTimeBase(seeking_stream->time_base, seek_time),
// Always seek to a timestamp <= to the desired timestamp.
AVSEEK_FLAG_BACKWARD),
base::Bind(
&FFmpegDemuxer::OnSeekFrameDone, weak_factory_.GetWeakPtr(), cb));
}
void FFmpegDemuxer::Initialize(DemuxerHost* host,
const PipelineStatusCB& status_cb,
bool enable_text_tracks) {
DCHECK(task_runner_->BelongsToCurrentThread());
host_ = host;
text_enabled_ = enable_text_tracks;
url_protocol_.reset(new BlockingUrlProtocol(data_source_, BindToCurrentLoop(
base::Bind(&FFmpegDemuxer::OnDataSourceError, base::Unretained(this)))));
glue_.reset(new FFmpegGlue(url_protocol_.get()));
AVFormatContext* format_context = glue_->format_context();
// Disable ID3v1 tag reading to avoid costly seeks to end of file for data we
// don't use. FFmpeg will only read ID3v1 tags if no other metadata is
// available, so add a metadata entry to ensure some is always present.
av_dict_set(&format_context->metadata, "skip_id3v1_tags", "", 0);
// Ensure ffmpeg doesn't give up too early while looking for stream params;
// this does not increase the amount of data downloaded. The default value
// is 5 AV_TIME_BASE units (1 second each), which prevents some oddly muxed
// streams from being detected properly; this value was chosen arbitrarily.
format_context->max_analyze_duration2 = 60 * AV_TIME_BASE;
// Open the AVFormatContext using our glue layer.
CHECK(blocking_thread_.Start());
base::PostTaskAndReplyWithResult(
blocking_thread_.message_loop_proxy().get(),
FROM_HERE,
base::Bind(&FFmpegGlue::OpenContext, base::Unretained(glue_.get())),
base::Bind(&FFmpegDemuxer::OnOpenContextDone,
weak_factory_.GetWeakPtr(),
status_cb));
}
base::Time FFmpegDemuxer::GetTimelineOffset() const {
return timeline_offset_;
}
DemuxerStream* FFmpegDemuxer::GetStream(DemuxerStream::Type type) {
DCHECK(task_runner_->BelongsToCurrentThread());
return GetFFmpegStream(type);
}
FFmpegDemuxerStream* FFmpegDemuxer::GetFFmpegStream(
DemuxerStream::Type type) const {
StreamVector::const_iterator iter;
for (iter = streams_.begin(); iter != streams_.end(); ++iter) {
if (*iter && (*iter)->type() == type) {
return *iter;
}
}
return NULL;
}
base::TimeDelta FFmpegDemuxer::GetStartTime() const {
return std::max(start_time_, base::TimeDelta());
}
void FFmpegDemuxer::AddTextStreams() {
DCHECK(task_runner_->BelongsToCurrentThread());
for (StreamVector::size_type idx = 0; idx < streams_.size(); ++idx) {
FFmpegDemuxerStream* stream = streams_[idx];
if (stream == NULL || stream->type() != DemuxerStream::TEXT)
continue;
TextKind kind = stream->GetTextKind();
std::string title = stream->GetMetadata("title");
std::string language = stream->GetMetadata("language");
// TODO: Implement "id" metadata in FFMPEG.
// See: http://crbug.com/323183
host_->AddTextStream(stream, TextTrackConfig(kind, title, language,
std::string()));
}
}
// Helper for calculating the bitrate of the media based on information stored
// in |format_context| or failing that the size and duration of the media.
//
// Returns 0 if a bitrate could not be determined.
static int CalculateBitrate(
AVFormatContext* format_context,
const base::TimeDelta& duration,
int64 filesize_in_bytes) {
// If there is a bitrate set on the container, use it.
if (format_context->bit_rate > 0)
return format_context->bit_rate;
// Then try to sum the bitrates individually per stream.
int bitrate = 0;
for (size_t i = 0; i < format_context->nb_streams; ++i) {
AVCodecContext* codec_context = format_context->streams[i]->codec;
bitrate += codec_context->bit_rate;
}
if (bitrate > 0)
return bitrate;
// See if we can approximate the bitrate as long as we have a filesize and
// valid duration.
if (duration.InMicroseconds() <= 0 ||
duration == kInfiniteDuration() ||
filesize_in_bytes == 0) {
return 0;
}
// Do math in floating point as we'd overflow an int64 if the filesize was
// larger than ~1073GB.
double bytes = filesize_in_bytes;
double duration_us = duration.InMicroseconds();
return bytes * 8000000.0 / duration_us;
}
void FFmpegDemuxer::OnOpenContextDone(const PipelineStatusCB& status_cb,
bool result) {
DCHECK(task_runner_->BelongsToCurrentThread());
if (!blocking_thread_.IsRunning()) {
status_cb.Run(PIPELINE_ERROR_ABORT);
return;
}
if (!result) {
status_cb.Run(DEMUXER_ERROR_COULD_NOT_OPEN);
return;
}
// Fully initialize AVFormatContext by parsing the stream a little.
base::PostTaskAndReplyWithResult(
blocking_thread_.message_loop_proxy().get(),
FROM_HERE,
base::Bind(&avformat_find_stream_info,
glue_->format_context(),
static_cast<AVDictionary**>(NULL)),
base::Bind(&FFmpegDemuxer::OnFindStreamInfoDone,
weak_factory_.GetWeakPtr(),
status_cb));
}
void FFmpegDemuxer::OnFindStreamInfoDone(const PipelineStatusCB& status_cb,
int result) {
DCHECK(task_runner_->BelongsToCurrentThread());
if (!blocking_thread_.IsRunning() || !data_source_) {
status_cb.Run(PIPELINE_ERROR_ABORT);
return;
}
if (result < 0) {
status_cb.Run(DEMUXER_ERROR_COULD_NOT_PARSE);
return;
}
// Create demuxer stream entries for each possible AVStream. Each stream
// is examined to determine if it is supported or not (is the codec enabled
// for it in this release?). Unsupported streams are skipped, allowing for
// partial playback. At least one audio or video stream must be playable.
AVFormatContext* format_context = glue_->format_context();
streams_.resize(format_context->nb_streams);
// Estimate the start time for each stream by looking through the packets
// buffered during avformat_find_stream_info(). These values will be
// considered later when determining the actual stream start time.
//
// These packets haven't been completely processed yet, so only look through
// these values if the AVFormatContext has a valid start time.
//
// If no estimate is found, the stream entry will be kInfiniteDuration().
std::vector<base::TimeDelta> start_time_estimates(format_context->nb_streams,
kInfiniteDuration());
if (format_context->packet_buffer &&
format_context->start_time != static_cast<int64>(AV_NOPTS_VALUE)) {
struct AVPacketList* packet_buffer = format_context->packet_buffer;
while (packet_buffer != format_context->packet_buffer_end) {
DCHECK_LT(static_cast<size_t>(packet_buffer->pkt.stream_index),
start_time_estimates.size());
const AVStream* stream =
format_context->streams[packet_buffer->pkt.stream_index];
if (packet_buffer->pkt.pts != static_cast<int64>(AV_NOPTS_VALUE)) {
const base::TimeDelta packet_pts =
ConvertFromTimeBase(stream->time_base, packet_buffer->pkt.pts);
if (packet_pts < start_time_estimates[stream->index])
start_time_estimates[stream->index] = packet_pts;
}
packet_buffer = packet_buffer->next;
}
}
AVStream* audio_stream = NULL;
AudioDecoderConfig audio_config;
AVStream* video_stream = NULL;
VideoDecoderConfig video_config;
// If available, |start_time_| will be set to the lowest stream start time.
start_time_ = kInfiniteDuration();
base::TimeDelta max_duration;
for (size_t i = 0; i < format_context->nb_streams; ++i) {
AVStream* stream = format_context->streams[i];
const AVCodecContext* codec_context = stream->codec;
const AVMediaType codec_type = codec_context->codec_type;
if (codec_type == AVMEDIA_TYPE_AUDIO) {
if (audio_stream)
continue;
// Log the codec detected, whether it is supported or not.
UMA_HISTOGRAM_SPARSE_SLOWLY("Media.DetectedAudioCodec",
codec_context->codec_id);
// Ensure the codec is supported. IsValidConfig() also checks that the
// channel layout and sample format are valid.
AVStreamToAudioDecoderConfig(stream, &audio_config, false);
if (!audio_config.IsValidConfig())
continue;
audio_stream = stream;
} else if (codec_type == AVMEDIA_TYPE_VIDEO) {
if (video_stream)
continue;
// Log the codec detected, whether it is supported or not.
UMA_HISTOGRAM_SPARSE_SLOWLY("Media.DetectedVideoCodec",
codec_context->codec_id);
// Ensure the codec is supported. IsValidConfig() also checks that the
// frame size and visible size are valid.
AVStreamToVideoDecoderConfig(stream, &video_config, false);
if (!video_config.IsValidConfig())
continue;
video_stream = stream;
} else if (codec_type == AVMEDIA_TYPE_SUBTITLE) {
if (codec_context->codec_id != AV_CODEC_ID_WEBVTT || !text_enabled_) {
continue;
}
} else {
continue;
}
streams_[i] = new FFmpegDemuxerStream(this, stream);
max_duration = std::max(max_duration, streams_[i]->duration());
const base::TimeDelta start_time =
ExtractStartTime(stream, start_time_estimates[i]);
const bool has_start_time = start_time != kNoTimestamp();
// Always prefer the video stream for seeking. If none exists, we'll swap
// the fallback stream with the preferred stream below.
if (codec_type == AVMEDIA_TYPE_VIDEO) {
preferred_stream_for_seeking_ =
StreamSeekInfo(i, has_start_time ? start_time : base::TimeDelta());
}
if (!has_start_time)
continue;
if (start_time < start_time_) {
start_time_ = start_time;
// Choose the stream with the lowest starting time as the fallback stream
// for seeking. Video should always be preferred.
fallback_stream_for_seeking_ = StreamSeekInfo(i, start_time);
}
}
if (!audio_stream && !video_stream) {
status_cb.Run(DEMUXER_ERROR_NO_SUPPORTED_STREAMS);
return;
}
if (text_enabled_)
AddTextStreams();
if (format_context->duration != static_cast<int64_t>(AV_NOPTS_VALUE)) {
// If there is a duration value in the container use that to find the
// maximum between it and the duration from A/V streams.
const AVRational av_time_base = {1, AV_TIME_BASE};
max_duration =
std::max(max_duration,
ConvertFromTimeBase(av_time_base, format_context->duration));
} else {
// The duration is unknown, in which case this is likely a live stream.
max_duration = kInfiniteDuration();
}
// Ogg has some peculiarities around negative timestamps, so use this flag to
// setup the FFmpegDemuxerStreams appropriately.
//
// Post-decode frame dropping for packets with negative timestamps is outlined
// in section A.2 in the Ogg Vorbis spec:
// http://xiph.org/vorbis/doc/Vorbis_I_spec.html
if (strcmp(format_context->iformat->name, "ogg") == 0 && audio_stream &&
audio_stream->codec->codec_id == AV_CODEC_ID_VORBIS) {
for (size_t i = 0; i < streams_.size(); ++i) {
if (streams_[i])
streams_[i]->enable_negative_timestamp_fixups_for_ogg();
}
// Fixup the seeking information to avoid selecting the audio stream simply
// because it has a lower starting time.
if (fallback_stream_for_seeking_.first == audio_stream->index &&
fallback_stream_for_seeking_.second < base::TimeDelta()) {
fallback_stream_for_seeking_.second = base::TimeDelta();
}
}
// If no start time could be determined, default to zero and prefer the video
// stream over the audio stream for seeking. E.g., The WAV demuxer does not
// put timestamps on its frames.
if (start_time_ == kInfiniteDuration()) {
start_time_ = base::TimeDelta();
preferred_stream_for_seeking_ = StreamSeekInfo(
video_stream ? video_stream->index : audio_stream->index, start_time_);
} else if (!video_stream) {
// If no video stream exists, use the audio or text stream found above.
preferred_stream_for_seeking_ = fallback_stream_for_seeking_;
}
// MPEG-4 B-frames cause grief for a simple container like AVI. Enable PTS
// generation so we always get timestamps, see http://crbug.com/169570
if (strcmp(format_context->iformat->name, "avi") == 0)
format_context->flags |= AVFMT_FLAG_GENPTS;
// For testing purposes, don't overwrite the timeline offset if set already.
if (timeline_offset_.is_null())
timeline_offset_ = ExtractTimelineOffset(format_context);
// Since we're shifting the externally visible start time to zero, we need to
// adjust the timeline offset to compensate.
if (!timeline_offset_.is_null() && start_time_ < base::TimeDelta())
timeline_offset_ += start_time_;
if (max_duration == kInfiniteDuration() && !timeline_offset_.is_null()) {
SetLiveness(DemuxerStream::LIVENESS_LIVE);
} else if (max_duration != kInfiniteDuration()) {
SetLiveness(DemuxerStream::LIVENESS_RECORDED);
} else {
SetLiveness(DemuxerStream::LIVENESS_UNKNOWN);
}
// Good to go: set the duration and bitrate and notify we're done
// initializing.
host_->SetDuration(max_duration);
duration_known_ = (max_duration != kInfiniteDuration());
int64 filesize_in_bytes = 0;
url_protocol_->GetSize(&filesize_in_bytes);
bitrate_ = CalculateBitrate(format_context, max_duration, filesize_in_bytes);
if (bitrate_ > 0)
data_source_->SetBitrate(bitrate_);
// Audio logging
if (audio_stream) {
AVCodecContext* audio_codec = audio_stream->codec;
media_log_->SetBooleanProperty("found_audio_stream", true);
SampleFormat sample_format = audio_config.sample_format();
std::string sample_name = SampleFormatToString(sample_format);
media_log_->SetStringProperty("audio_sample_format", sample_name);
AVCodec* codec = avcodec_find_decoder(audio_codec->codec_id);
if (codec) {
media_log_->SetStringProperty("audio_codec_name", codec->name);
}
media_log_->SetIntegerProperty("audio_channels_count",
audio_codec->channels);
media_log_->SetIntegerProperty("audio_samples_per_second",
audio_config.samples_per_second());
} else {
media_log_->SetBooleanProperty("found_audio_stream", false);
}
// Video logging
if (video_stream) {
AVCodecContext* video_codec = video_stream->codec;
media_log_->SetBooleanProperty("found_video_stream", true);
AVCodec* codec = avcodec_find_decoder(video_codec->codec_id);
if (codec) {
media_log_->SetStringProperty("video_codec_name", codec->name);
} else if (video_codec->codec_id == AV_CODEC_ID_VP9) {
// ffmpeg doesn't know about VP9 decoder. So we need to log it explicitly.
media_log_->SetStringProperty("video_codec_name", "vp9");
}
media_log_->SetIntegerProperty("width", video_codec->width);
media_log_->SetIntegerProperty("height", video_codec->height);
media_log_->SetIntegerProperty("coded_width",
video_codec->coded_width);
media_log_->SetIntegerProperty("coded_height",
video_codec->coded_height);
media_log_->SetStringProperty(
"time_base",
base::StringPrintf("%d/%d",
video_codec->time_base.num,
video_codec->time_base.den));
media_log_->SetStringProperty(
"video_format", VideoFrame::FormatToString(video_config.format()));
media_log_->SetBooleanProperty("video_is_encrypted",
video_config.is_encrypted());
} else {
media_log_->SetBooleanProperty("found_video_stream", false);
}
media_log_->SetTimeProperty("max_duration", max_duration);
media_log_->SetTimeProperty("start_time", start_time_);
media_log_->SetIntegerProperty("bitrate", bitrate_);
status_cb.Run(PIPELINE_OK);
}
void FFmpegDemuxer::OnSeekFrameDone(const PipelineStatusCB& cb, int result) {
DCHECK(task_runner_->BelongsToCurrentThread());
CHECK(pending_seek_);
pending_seek_ = false;
if (!blocking_thread_.IsRunning()) {
cb.Run(PIPELINE_ERROR_ABORT);
return;
}
if (result < 0) {
// Use VLOG(1) instead of NOTIMPLEMENTED() to prevent the message being
// captured from stdout and contaminates testing.
// TODO(scherkus): Implement this properly and signal error (BUG=23447).
VLOG(1) << "Not implemented";
}
// Tell streams to flush buffers due to seeking.
StreamVector::iterator iter;
for (iter = streams_.begin(); iter != streams_.end(); ++iter) {
if (*iter)
(*iter)->FlushBuffers();
}
// Resume reading until capacity.
ReadFrameIfNeeded();
// Notify we're finished seeking.
cb.Run(PIPELINE_OK);
}
void FFmpegDemuxer::ReadFrameIfNeeded() {
DCHECK(task_runner_->BelongsToCurrentThread());
// Make sure we have work to do before reading.
if (!blocking_thread_.IsRunning() || !StreamsHaveAvailableCapacity() ||
pending_read_ || pending_seek_) {
return;
}
// Allocate and read an AVPacket from the media. Save |packet_ptr| since
// evaluation order of packet.get() and base::Passed(&packet) is
// undefined.
ScopedAVPacket packet(new AVPacket());
AVPacket* packet_ptr = packet.get();
pending_read_ = true;
base::PostTaskAndReplyWithResult(
blocking_thread_.message_loop_proxy().get(),
FROM_HERE,
base::Bind(&av_read_frame, glue_->format_context(), packet_ptr),
base::Bind(&FFmpegDemuxer::OnReadFrameDone,
weak_factory_.GetWeakPtr(),
base::Passed(&packet)));
}
void FFmpegDemuxer::OnReadFrameDone(ScopedAVPacket packet, int result) {
DCHECK(task_runner_->BelongsToCurrentThread());
DCHECK(pending_read_);
pending_read_ = false;
if (!blocking_thread_.IsRunning() || pending_seek_) {
return;
}
// Consider the stream as ended if:
// - either underlying ffmpeg returned an error
// - or FFMpegDemuxer reached the maximum allowed memory usage.
if (result < 0 || IsMaxMemoryUsageReached()) {
// Update the duration based on the highest elapsed time across all streams
// if it was previously unknown.
if (!duration_known_) {
base::TimeDelta max_duration;
for (StreamVector::iterator iter = streams_.begin();
iter != streams_.end();
++iter) {
if (!*iter)
continue;
base::TimeDelta duration = (*iter)->GetElapsedTime();
if (duration != kNoTimestamp() && duration > max_duration)
max_duration = duration;
}
if (max_duration > base::TimeDelta()) {
host_->SetDuration(max_duration);
duration_known_ = true;
}
}
// If we have reached the end of stream, tell the downstream filters about
// the event.
StreamHasEnded();
return;
}
// Queue the packet with the appropriate stream.
DCHECK_GE(packet->stream_index, 0);
DCHECK_LT(packet->stream_index, static_cast<int>(streams_.size()));
// Defend against ffmpeg giving us a bad stream index.
if (packet->stream_index >= 0 &&
packet->stream_index < static_cast<int>(streams_.size()) &&
streams_[packet->stream_index]) {
// TODO(scherkus): Fix demuxing upstream to never return packets w/o data
// when av_read_frame() returns success code. See bug comment for ideas:
//
// https://code.google.com/p/chromium/issues/detail?id=169133#c10
if (!packet->data) {
ScopedAVPacket new_packet(new AVPacket());
av_new_packet(new_packet.get(), 0);
av_packet_copy_props(new_packet.get(), packet.get());
packet.swap(new_packet);
}
// Special case for opus in ogg. FFmpeg is pre-trimming the codec delay
// from the packet timestamp. Chrome expects to handle this itself inside
// the decoder, so shift timestamps by the delay in this case.
// TODO(dalecurtis): Try to get fixed upstream. See http://crbug.com/328207
if (strcmp(glue_->format_context()->iformat->name, "ogg") == 0) {
const AVCodecContext* codec_context =
glue_->format_context()->streams[packet->stream_index]->codec;
if (codec_context->codec_id == AV_CODEC_ID_OPUS &&
codec_context->delay > 0) {
packet->pts += codec_context->delay;
}
}
FFmpegDemuxerStream* demuxer_stream = streams_[packet->stream_index];
demuxer_stream->EnqueuePacket(packet.Pass());
}
// Keep reading until we've reached capacity.
ReadFrameIfNeeded();
}
bool FFmpegDemuxer::StreamsHaveAvailableCapacity() {
DCHECK(task_runner_->BelongsToCurrentThread());
StreamVector::iterator iter;
for (iter = streams_.begin(); iter != streams_.end(); ++iter) {
if (*iter && (*iter)->HasAvailableCapacity()) {
return true;
}
}
return false;
}
bool FFmpegDemuxer::IsMaxMemoryUsageReached() const {
DCHECK(task_runner_->BelongsToCurrentThread());
// Max allowed memory usage, all streams combined.
const size_t kDemuxerMemoryLimit = 150 * 1024 * 1024;
size_t memory_left = kDemuxerMemoryLimit;
for (StreamVector::const_iterator iter = streams_.begin();
iter != streams_.end(); ++iter) {
if (!(*iter))
continue;
size_t stream_memory_usage = (*iter)->MemoryUsage();
if (stream_memory_usage > memory_left)
return true;
memory_left -= stream_memory_usage;
}
return false;
}
void FFmpegDemuxer::StreamHasEnded() {
DCHECK(task_runner_->BelongsToCurrentThread());
StreamVector::iterator iter;
for (iter = streams_.begin(); iter != streams_.end(); ++iter) {
if (!*iter)
continue;
(*iter)->SetEndOfStream();
}
}
void FFmpegDemuxer::OnEncryptedMediaInitData(
const std::string& init_data_type,
const std::string& encryption_key_id) {
std::vector<uint8> key_id_local(encryption_key_id.begin(),
encryption_key_id.end());
encrypted_media_init_data_cb_.Run(init_data_type, key_id_local);
}
void FFmpegDemuxer::NotifyCapacityAvailable() {
DCHECK(task_runner_->BelongsToCurrentThread());
ReadFrameIfNeeded();
}
void FFmpegDemuxer::NotifyBufferingChanged() {
DCHECK(task_runner_->BelongsToCurrentThread());
Ranges<base::TimeDelta> buffered;
FFmpegDemuxerStream* audio = GetFFmpegStream(DemuxerStream::AUDIO);
FFmpegDemuxerStream* video = GetFFmpegStream(DemuxerStream::VIDEO);
if (audio && video) {
buffered = audio->GetBufferedRanges().IntersectionWith(
video->GetBufferedRanges());
} else if (audio) {
buffered = audio->GetBufferedRanges();
} else if (video) {
buffered = video->GetBufferedRanges();
}
for (size_t i = 0; i < buffered.size(); ++i)
host_->AddBufferedTimeRange(buffered.start(i), buffered.end(i));
}
void FFmpegDemuxer::OnDataSourceError() {
host_->OnDemuxerError(PIPELINE_ERROR_READ);
}
void FFmpegDemuxer::SetLiveness(DemuxerStream::Liveness liveness) {
DCHECK(task_runner_->BelongsToCurrentThread());
for (const auto& stream : streams_) { // |stream| is a ref to a pointer.
if (stream)
stream->SetLiveness(liveness);
}
}
} // namespace media