blob: d986deb0b6815449b30a25489c2a1369d1390d96 [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/webm/webm_stream_parser.h"
#include "base/callback.h"
#include "base/logging.h"
#include "media/ffmpeg/ffmpeg_common.h"
#include "media/filters/ffmpeg_glue.h"
#include "media/filters/in_memory_url_protocol.h"
#include "media/webm/webm_cluster_parser.h"
#include "media/webm/webm_constants.h"
#include "media/webm/webm_content_encodings.h"
#include "media/webm/webm_info_parser.h"
#include "media/webm/webm_tracks_parser.h"
namespace media {
// Helper class that uses FFmpeg to create AudioDecoderConfig &
// VideoDecoderConfig objects.
//
// This dependency on FFmpeg can be removed once we update WebMTracksParser
// to parse the necessary data to construct AudioDecoderConfig &
// VideoDecoderConfig objects. http://crbug.com/108756
class FFmpegConfigHelper {
public:
FFmpegConfigHelper();
~FFmpegConfigHelper();
bool Parse(const uint8* data, int size);
const AudioDecoderConfig& audio_config() const;
const VideoDecoderConfig& video_config() const;
private:
static const uint8 kWebMHeader[];
static const int kSegmentSizeOffset;
static const uint8 kEmptyCluster[];
AVFormatContext* CreateFormatContext(const uint8* data, int size);
bool SetupStreamConfigs();
AudioDecoderConfig audio_config_;
VideoDecoderConfig video_config_;
// Backing buffer for |url_protocol_|.
scoped_array<uint8> url_protocol_buffer_;
// Protocol used by |format_context_|. It must outlive the context object.
scoped_ptr<FFmpegURLProtocol> url_protocol_;
// FFmpeg format context for this demuxer. It is created by
// avformat_open_input() during demuxer initialization and cleaned up with
// DestroyAVFormatContext() in the destructor.
AVFormatContext* format_context_;
DISALLOW_COPY_AND_ASSIGN(FFmpegConfigHelper);
};
// WebM File Header. This is prepended to the INFO & TRACKS
// data passed to Init() before handing it to FFmpeg. Essentially
// we are making the INFO & TRACKS data look like a small WebM
// file so we can use FFmpeg to initialize the AVFormatContext.
const uint8 FFmpegConfigHelper::kWebMHeader[] = {
0x1A, 0x45, 0xDF, 0xA3, 0x9F, // EBML (size = 0x1f)
0x42, 0x86, 0x81, 0x01, // EBMLVersion = 1
0x42, 0xF7, 0x81, 0x01, // EBMLReadVersion = 1
0x42, 0xF2, 0x81, 0x04, // EBMLMaxIDLength = 4
0x42, 0xF3, 0x81, 0x08, // EBMLMaxSizeLength = 8
0x42, 0x82, 0x84, 0x77, 0x65, 0x62, 0x6D, // DocType = "webm"
0x42, 0x87, 0x81, 0x02, // DocTypeVersion = 2
0x42, 0x85, 0x81, 0x02, // DocTypeReadVersion = 2
// EBML end
0x18, 0x53, 0x80, 0x67, // Segment
0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // segment(size = 0)
// INFO goes here.
};
// Offset of the segment size field in kWebMHeader. Used to update
// the segment size field before handing the buffer to FFmpeg.
const int FFmpegConfigHelper::kSegmentSizeOffset = sizeof(kWebMHeader) - 8;
const uint8 FFmpegConfigHelper::kEmptyCluster[] = {
0x1F, 0x43, 0xB6, 0x75, 0x80 // CLUSTER (size = 0)
};
FFmpegConfigHelper::FFmpegConfigHelper() : format_context_(NULL) {}
FFmpegConfigHelper::~FFmpegConfigHelper() {
if (!format_context_)
return;
DestroyAVFormatContext(format_context_);
format_context_ = NULL;
if (url_protocol_.get()) {
FFmpegGlue::GetInstance()->RemoveProtocol(url_protocol_.get());
url_protocol_.reset();
url_protocol_buffer_.reset();
}
}
bool FFmpegConfigHelper::Parse(const uint8* data, int size) {
format_context_ = CreateFormatContext(data, size);
return format_context_ && SetupStreamConfigs();
}
const AudioDecoderConfig& FFmpegConfigHelper::audio_config() const {
return audio_config_;
}
const VideoDecoderConfig& FFmpegConfigHelper::video_config() const {
return video_config_;
}
AVFormatContext* FFmpegConfigHelper::CreateFormatContext(const uint8* data,
int size) {
DCHECK(!url_protocol_.get());
DCHECK(!url_protocol_buffer_.get());
int segment_size = size + sizeof(kEmptyCluster);
int buf_size = sizeof(kWebMHeader) + segment_size;
url_protocol_buffer_.reset(new uint8[buf_size]);
uint8* buf = url_protocol_buffer_.get();
memcpy(buf, kWebMHeader, sizeof(kWebMHeader));
memcpy(buf + sizeof(kWebMHeader), data, size);
memcpy(buf + sizeof(kWebMHeader) + size, kEmptyCluster,
sizeof(kEmptyCluster));
// Update the segment size in the buffer.
int64 tmp = (segment_size & GG_LONGLONG(0x00FFFFFFFFFFFFFF)) |
GG_LONGLONG(0x0100000000000000);
for (int i = 0; i < 8; i++) {
buf[kSegmentSizeOffset + i] = (tmp >> (8 * (7 - i))) & 0xff;
}
url_protocol_.reset(new InMemoryUrlProtocol(buf, buf_size, true));
std::string key = FFmpegGlue::GetInstance()->AddProtocol(url_protocol_.get());
// Open FFmpeg AVFormatContext.
AVFormatContext* context = NULL;
int result = avformat_open_input(&context, key.c_str(), NULL, NULL);
if (result < 0)
return NULL;
return context;
}
bool FFmpegConfigHelper::SetupStreamConfigs() {
int result = avformat_find_stream_info(format_context_, NULL);
if (result < 0)
return false;
bool no_supported_streams = true;
for (size_t i = 0; i < format_context_->nb_streams; ++i) {
AVStream* stream = format_context_->streams[i];
AVCodecContext* codec_context = stream->codec;
AVMediaType codec_type = codec_context->codec_type;
if (codec_type == AVMEDIA_TYPE_AUDIO &&
stream->codec->codec_id == CODEC_ID_VORBIS &&
!audio_config_.IsValidConfig()) {
AVCodecContextToAudioDecoderConfig(stream->codec, &audio_config_);
no_supported_streams = false;
continue;
}
if (codec_type == AVMEDIA_TYPE_VIDEO &&
stream->codec->codec_id == CODEC_ID_VP8 &&
!video_config_.IsValidConfig()) {
AVStreamToVideoDecoderConfig(stream, &video_config_);
no_supported_streams = false;
continue;
}
}
return !no_supported_streams;
}
WebMStreamParser::WebMStreamParser()
: state_(WAITING_FOR_INIT),
host_(NULL) {
}
WebMStreamParser::~WebMStreamParser() {}
void WebMStreamParser::Init(const InitCB& init_cb, StreamParserHost* host) {
DCHECK_EQ(state_, WAITING_FOR_INIT);
DCHECK(init_cb_.is_null());
DCHECK(!host_);
DCHECK(!init_cb.is_null());
DCHECK(host);
ChangeState(PARSING_HEADERS);
init_cb_ = init_cb;
host_ = host;
}
void WebMStreamParser::Flush() {
DCHECK_NE(state_, WAITING_FOR_INIT);
if (state_ != PARSING_CLUSTERS)
return;
cluster_parser_->Reset();
}
int WebMStreamParser::Parse(const uint8* buf, int size) {
DCHECK_NE(state_, WAITING_FOR_INIT);
if (state_ == PARSING_HEADERS)
return ParseInfoAndTracks(buf, size);
if (state_ == PARSING_CLUSTERS)
return ParseCluster(buf, size);
return -1;
}
void WebMStreamParser::ChangeState(State new_state) {
state_ = new_state;
}
int WebMStreamParser::ParseInfoAndTracks(const uint8* data, int size) {
DCHECK(data);
DCHECK_GT(size, 0);
const uint8* cur = data;
int cur_size = size;
int bytes_parsed = 0;
int id;
int64 element_size;
int result = WebMParseElementHeader(cur, cur_size, &id, &element_size);
if (result <= 0)
return result;
switch (id) {
case kWebMIdEBMLHeader:
case kWebMIdSeekHead:
case kWebMIdVoid:
case kWebMIdCRC32:
case kWebMIdCues:
if (cur_size < (result + element_size)) {
// We don't have the whole element yet. Signal we need more data.
return 0;
}
// Skip the element.
return result + element_size;
break;
case kWebMIdSegment:
// Just consume the segment header.
return result;
break;
case kWebMIdInfo:
// We've found the element we are looking for.
break;
default:
DVLOG(1) << "Unexpected ID 0x" << std::hex << id;
return -1;
}
WebMInfoParser info_parser;
result = info_parser.Parse(cur, cur_size);
if (result <= 0)
return result;
cur += result;
cur_size -= result;
bytes_parsed += result;
WebMTracksParser tracks_parser(info_parser.timecode_scale());
result = tracks_parser.Parse(cur, cur_size);
if (result <= 0)
return result;
bytes_parsed += result;
base::TimeDelta duration = kInfiniteDuration();
if (info_parser.duration() > 0) {
double mult = info_parser.timecode_scale() / 1000.0;
int64 duration_in_us = info_parser.duration() * mult;
duration = base::TimeDelta::FromMicroseconds(duration_in_us);
}
FFmpegConfigHelper config_helper;
if (!config_helper.Parse(data, bytes_parsed))
return -1;
if (config_helper.audio_config().IsValidConfig())
host_->OnNewAudioConfig(config_helper.audio_config());
if (config_helper.video_config().IsValidConfig())
host_->OnNewVideoConfig(config_helper.video_config());
cluster_parser_.reset(new WebMClusterParser(
info_parser.timecode_scale(),
tracks_parser.audio_track_num(),
tracks_parser.audio_default_duration(),
tracks_parser.video_track_num(),
tracks_parser.video_default_duration(),
tracks_parser.video_encryption_key_id(),
tracks_parser.video_encryption_key_id_size()));
ChangeState(PARSING_CLUSTERS);
init_cb_.Run(true, duration);
init_cb_.Reset();
return bytes_parsed;
}
int WebMStreamParser::ParseCluster(const uint8* data, int size) {
if (!cluster_parser_.get())
return -1;
int id;
int64 element_size;
int result = WebMParseElementHeader(data, size, &id, &element_size);
if (result <= 0)
return result;
if (id == kWebMIdCues) {
if (size < (result + element_size)) {
// We don't have the whole element yet. Signal we need more data.
return 0;
}
// Skip the element.
return result + element_size;
}
int bytes_parsed = cluster_parser_->Parse(data, size);
if (bytes_parsed <= 0)
return bytes_parsed;
const StreamParserHost::BufferQueue& audio_buffers =
cluster_parser_->audio_buffers();
const StreamParserHost::BufferQueue& video_buffers =
cluster_parser_->video_buffers();
if (!audio_buffers.empty() && !host_->OnAudioBuffers(audio_buffers))
return -1;
if (!video_buffers.empty() && !host_->OnVideoBuffers(video_buffers))
return -1;
return bytes_parsed;
}
} // namespace media