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// 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_cluster_parser.h"
#include "base/logging.h"
#include "media/base/data_buffer.h"
#include "media/webm/webm_constants.h"
namespace media {
static Buffer* CreateBuffer(const uint8* data, size_t size) {
scoped_array<uint8> buf(new uint8[size]);
memcpy(buf.get(), data, size);
return new DataBuffer(buf.Pass(), size);
}
WebMClusterParser::WebMClusterParser(int64 timecode_scale,
int audio_track_num,
base::TimeDelta audio_default_duration,
int video_track_num,
base::TimeDelta video_default_duration)
: timecode_multiplier_(timecode_scale / 1000.0),
audio_track_num_(audio_track_num),
audio_default_duration_(audio_default_duration),
video_track_num_(video_track_num),
video_default_duration_(video_default_duration),
parser_(kWebMIdCluster, this),
last_block_timecode_(-1),
cluster_timecode_(-1) {
}
WebMClusterParser::~WebMClusterParser() {}
void WebMClusterParser::Reset() {
audio_buffers_.clear();
video_buffers_.clear();
last_block_timecode_ = -1;
cluster_timecode_ = -1;
parser_.Reset();
}
int WebMClusterParser::Parse(const uint8* buf, int size) {
audio_buffers_.clear();
video_buffers_.clear();
int result = parser_.Parse(buf, size);
if (result <= 0)
return result;
if (parser_.IsParsingComplete()) {
// Reset the parser if we're done parsing so that
// it is ready to accept another cluster on the next
// call.
parser_.Reset();
last_block_timecode_ = -1;
cluster_timecode_ = -1;
}
return result;
}
WebMParserClient* WebMClusterParser::OnListStart(int id) {
if (id == kWebMIdCluster)
cluster_timecode_ = -1;
return this;
}
bool WebMClusterParser::OnListEnd(int id) {
if (id == kWebMIdCluster)
cluster_timecode_ = -1;
return true;
}
bool WebMClusterParser::OnUInt(int id, int64 val) {
if (id == kWebMIdTimecode) {
if (cluster_timecode_ != -1)
return false;
cluster_timecode_ = val;
}
return true;
}
bool WebMClusterParser::OnSimpleBlock(int track_num, int timecode,
int flags,
const uint8* data, int size) {
if (cluster_timecode_ == -1) {
DVLOG(1) << "Got SimpleBlock before cluster timecode.";
return false;
}
if (timecode < 0) {
DVLOG(1) << "Got SimpleBlock with negative timecode offset " << timecode;
return false;
}
if (last_block_timecode_ != -1 && timecode < last_block_timecode_) {
DVLOG(1) << "Got SimpleBlock with a timecode before the previous block.";
return false;
}
last_block_timecode_ = timecode;
base::TimeDelta timestamp = base::TimeDelta::FromMicroseconds(
(cluster_timecode_ + timecode) * timecode_multiplier_);
scoped_refptr<Buffer> buffer(CreateBuffer(data, size));
buffer->SetTimestamp(timestamp);
BufferQueue* queue = NULL;
if (track_num == audio_track_num_) {
buffer->SetDuration(audio_default_duration_);
queue = &audio_buffers_;
} else if (track_num == video_track_num_) {
buffer->SetDuration(video_default_duration_);
queue = &video_buffers_;
} else {
DVLOG(1) << "Unexpected track number " << track_num;
return false;
}
if (!queue->empty() &&
buffer->GetTimestamp() == queue->back()->GetTimestamp()) {
DVLOG(1) << "Got SimpleBlock timecode is not strictly monotonically "
<< "increasing for track " << track_num;
return false;
}
queue->push_back(buffer);
return true;
}
} // namespace media
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