Index: media/capture/webm_muxer.cc |
diff --git a/media/capture/webm_muxer.cc b/media/capture/webm_muxer.cc |
new file mode 100644 |
index 0000000000000000000000000000000000000000..8293fe7ab07b5d836bca806e743fda891c85a0a1 |
--- /dev/null |
+++ b/media/capture/webm_muxer.cc |
@@ -0,0 +1,129 @@ |
+// Copyright 2015 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/capture/webm_muxer.h" |
+ |
+#include <limits> |
+ |
+namespace media { |
+ |
+// Template to +1 a non-negative Natural number to make a strictly positive one. |
+template <typename NonNegativeNaturalType> |
+class PositiveInteger{ |
+ public: |
+ explicit PositiveInteger(NonNegativeNaturalType value) |
+ : value_(value + static_cast<NonNegativeNaturalType>(1)) { |
+ static_assert(std::numeric_limits<NonNegativeNaturalType>::is_integer && |
+ !std::numeric_limits<NonNegativeNaturalType>::is_signed, |
+ "NonNegativeNaturalType must be an unsigned integer type"); |
+ } |
+ NonNegativeNaturalType Value() const { return value_; } |
+ |
+ private: |
+ const NonNegativeNaturalType value_; |
+ |
+ DISALLOW_IMPLICIT_CONSTRUCTORS(PositiveInteger); |
+}; |
+ |
+WebmMuxer::WebmMuxer(const WriteDataCB& write_data_callback) |
+ : write_data_callback_(write_data_callback), |
+ position_(0), |
+ segment_(new mkvmuxer::Segment()) { |
+ DVLOG(2) << __FUNCTION__; |
+ DCHECK(thread_checker_.CalledOnValidThread()); |
+ segment_->Init(this); |
+ segment_->set_mode(mkvmuxer::Segment::kLive); |
+ segment_->OutputCues(false); |
+ |
+ mkvmuxer::SegmentInfo* const info = segment_->GetSegmentInfo(); |
+ info->set_writing_app("Chrome"); |
+ info->set_muxing_app("Chrome"); |
+} |
+ |
+WebmMuxer::~WebmMuxer() { |
+ DCHECK(thread_checker_.CalledOnValidThread()); |
+ DVLOG(2) << __FUNCTION__; |
+ segment_->Finalize(); |
+} |
+ |
+void WebmMuxer::AddVideoTrack(uint32_t track_number, |
+ const gfx::Size& frame_size, |
+ double frame_rate) { |
+ DCHECK(thread_checker_.CalledOnValidThread()); |
+ |
+ // |track_number|, a caller-side identifier, cannot be zero (!), see |
+ // http://www.matroska.org/technical/specs/index.html#Tracks |
+ const PositiveInteger<uint32_t> nonzero_track_number(track_number); |
+ DCHECK(!segment_->GetTrackByNumber(nonzero_track_number.Value())); |
+ |
+ segment_->AddVideoTrack(frame_size.width(), |
+ frame_size.height(), |
+ nonzero_track_number.Value()); |
+ mkvmuxer::VideoTrack* const video_track = |
+ reinterpret_cast<mkvmuxer::VideoTrack*>( |
+ segment_->GetTrackByNumber(nonzero_track_number.Value())); |
+ DCHECK(video_track); |
+ video_track->set_codec_id(mkvmuxer::Tracks::kVp8CodecId); |
+ DCHECK_EQ(video_track->crop_right(), 0ull); |
+ DCHECK_EQ(video_track->crop_left(), 0ull); |
+ DCHECK_EQ(video_track->crop_top(), 0ull); |
+ DCHECK_EQ(video_track->crop_bottom(), 0ull); |
+ |
+ video_track->set_frame_rate(frame_rate); |
+ video_track->set_default_duration(base::Time::kMicrosecondsPerSecond / |
+ frame_rate); |
+ // Change segment's timestamps to microseconds instead of milliseconds: |
+ // http://matroska.org/technical/specs/index.html#TimecodeScale |
+ segment_->GetSegmentInfo()->set_timecode_scale( |
+ base::Time::kNanosecondsPerMicrosecond); |
+} |
+ |
+void WebmMuxer::OnEncodedVideo(uint32_t track_number, |
+ const std::string& encoded_data, |
+ const base::TimeDelta& timedelta_us, |
miu
2015/07/18 00:29:39
naming: Remove _us suffix here too, and this shoul
mcasas
2015/07/20 16:25:15
Done.
|
+ bool keyframe) { |
+ DVLOG(2) << __FUNCTION__; |
+ DCHECK(thread_checker_.CalledOnValidThread()); |
+ |
+ // |track_number|, a caller-side identifier, cannot be zero (!), see |
+ // http://www.matroska.org/technical/specs/index.html#Tracks |
+ const PositiveInteger<uint32_t> nonzero_track_number(track_number); |
+ DCHECK(segment_->GetTrackByNumber(nonzero_track_number.Value())); |
+ |
+ segment_->AddFrame(reinterpret_cast<const uint8_t*>(encoded_data.data()), |
+ encoded_data.size(), |
+ nonzero_track_number.Value(), |
+ timedelta_us.InMicroseconds(), |
+ keyframe); |
+} |
+ |
+mkvmuxer::int32 WebmMuxer::Write(const void* buf, mkvmuxer::uint32 len) { |
+ DVLOG(3) << __FUNCTION__ << " length=" << len; |
+ DCHECK(thread_checker_.CalledOnValidThread()); |
+ write_data_callback_.Run(static_cast<const char*>(buf), len); |
+ position_ += len; |
+ return 0; |
+} |
+ |
+mkvmuxer::int64 WebmMuxer::Position() const { |
+ return position_.ValueOrDie(); |
+} |
+ |
+mkvmuxer::int32 WebmMuxer::Position(mkvmuxer::int64 position) { |
+ // The stream is not Seekable() so indicate we cannot set the position. |
+ return -1; |
+} |
+ |
+bool WebmMuxer::Seekable() const { |
+ return false; |
+} |
+ |
+void WebmMuxer::ElementStartNotify(mkvmuxer::uint64 element_id, |
+ mkvmuxer::int64 position) { |
+ // This method gets pinged before items are sent to |write_data_callback_|. |
+ DCHECK_GE(position, position_.ValueOrDefault(0)) |
+ << "Can't go back in a Live Mkv stream."; |
+} |
+ |
+} // namespace media |