Add libsimplewebm and libwebm thirdparty libraries

thirdparty/README.md

@@ -95,6 +95,12 @@ Files extracted from upstream source:
 - `scripts/pnglibconf.h.prebuilt` as `pnglibconf.h`
 
 
+## libsimplewebm
+
+- Upstream: https://github.com/zaps166/libsimplewebm
+- License: MIT, BSD-3-Clause
+
+
 ## libvorbis
 
 - Upstream: https://www.xiph.org/vorbis

thirdparty/libsimplewebm/LICENSE

+MIT License
+
+Copyright (c) 2016 Błażej Szczygieł
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

thirdparty/libsimplewebm/OpusVorbisDecoder.cpp

+/*
+	MIT License
+
+	Copyright (c) 2016 Błażej Szczygieł
+
+	Permission is hereby granted, free of charge, to any person obtaining a copy
+	of this software and associated documentation files (the "Software"), to deal
+	in the Software without restriction, including without limitation the rights
+	to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+	copies of the Software, and to permit persons to whom the Software is
+	furnished to do so, subject to the following conditions:
+
+	The above copyright notice and this permission notice shall be included in all
+	copies or substantial portions of the Software.
+
+	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+	IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+	FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+	AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+	LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+	OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+	SOFTWARE.
+*/
+
+#include "OpusVorbisDecoder.hpp"
+
+#include <vorbis/codec.h>
+#include <opus/opus.h>
+
+#include <string.h>
+
+struct VorbisDecoder
+{
+	vorbis_info info;
+	vorbis_dsp_state dspState;
+	vorbis_block block;
+	ogg_packet op;
+
+	bool hasDSPState, hasBlock;
+};
+
+/**/
+
+OpusVorbisDecoder::OpusVorbisDecoder(const WebMDemuxer &demuxer) :
+	m_vorbis(NULL), m_opus(NULL),
+	m_numSamples(0),
+	m_channels(demuxer.getChannels())
+{
+	switch (demuxer.getAudioCodec())
+	{
+		case WebMDemuxer::AUDIO_VORBIS:
+			if (openVorbis(demuxer))
+				return;
+			break;
+		case WebMDemuxer::AUDIO_OPUS:
+			if (openOpus(demuxer))
+				return;
+			break;
+		default:
+			return;
+	}
+	close();
+}
+OpusVorbisDecoder::~OpusVorbisDecoder()
+{
+	close();
+}
+
+bool OpusVorbisDecoder::isOpen() const
+{
+	return (m_vorbis || m_opus);
+}
+
+bool OpusVorbisDecoder::getPCMS16(WebMFrame &frame, short *buffer, int &numOutSamples)
+{
+	if (m_vorbis)
+	{
+		m_vorbis->op.packet = frame.buffer;
+		m_vorbis->op.bytes = frame.bufferSize;
+
+		if (vorbis_synthesis(&m_vorbis->block, &m_vorbis->op))
+			return false;
+		if (vorbis_synthesis_blockin(&m_vorbis->dspState, &m_vorbis->block))
+			return false;
+
+		const int maxSamples = getBufferSamples();
+		int samplesCount, count = 0;
+		float **pcm;
+		while ((samplesCount = vorbis_synthesis_pcmout(&m_vorbis->dspState, &pcm)))
+		{
+			const int toConvert = samplesCount <= maxSamples ? samplesCount : maxSamples;
+			for (int c = 0; c < m_channels; ++c)
+			{
+				float *samples = pcm[c];
+				for (int i = 0, j = c; i < toConvert; ++i, j += m_channels)
+				{
+					int sample = samples[i] * 32767.0f;
+					if (sample > 32767)
+						sample = 32767;
+					else if (sample < -32768)
+						sample = -32768;
+					buffer[count + j] = sample;
+				}
+			}
+			vorbis_synthesis_read(&m_vorbis->dspState, toConvert);
+			count += toConvert;
+		}
+
+		numOutSamples = count;
+		return true;
+	}
+	else if (m_opus)
+	{
+		const int samples = opus_decode(m_opus, frame.buffer, frame.bufferSize, buffer, m_numSamples, 0);
+		if (samples >= 0)
+		{
+			numOutSamples = samples;
+			return true;
+		}
+	}
+	return false;
+}
+
+bool OpusVorbisDecoder::openVorbis(const WebMDemuxer &demuxer)
+{
+	size_t extradataSize = 0;
+	const unsigned char *extradata = demuxer.getAudioExtradata(extradataSize);
+
+	if (extradataSize < 3 || !extradata || extradata[0] != 2)
+		return false;
+
+	size_t headerSize[3] = {0};
+	size_t offset = 1;
+
+	/* Calculate three headers sizes */
+	for (int i = 0; i < 2; ++i)
+	{
+		for (;;)
+		{
+			if (offset >= extradataSize)
+				return false;
+			headerSize[i] += extradata[offset];
+			if (extradata[offset++] < 0xFF)
+				break;
+		}
+	}
+	headerSize[2] = extradataSize - (headerSize[0] + headerSize[1] + offset);
+
+	if (headerSize[0] + headerSize[1] + headerSize[2] + offset != extradataSize)
+		return false;
+
+	ogg_packet op[3];
+	memset(op, 0, sizeof op);
+
+	op[0].packet = (unsigned char *)extradata + offset;
+	op[0].bytes = headerSize[0];
+	op[0].b_o_s = 1;
+
+	op[1].packet = (unsigned char *)extradata + offset + headerSize[0];
+	op[1].bytes = headerSize[1];
+
+	op[2].packet = (unsigned char *)extradata + offset + headerSize[0] + headerSize[1];
+	op[2].bytes = headerSize[2];
+
+	m_vorbis = new VorbisDecoder;
+	m_vorbis->hasDSPState = m_vorbis->hasBlock = false;
+	vorbis_info_init(&m_vorbis->info);
+
+	/* Upload three Vorbis headers into libvorbis */
+	vorbis_comment vc;
+	vorbis_comment_init(&vc);
+	for (int i = 0; i < 3; ++i)
+	{
+		if (vorbis_synthesis_headerin(&m_vorbis->info, &vc, &op[i]))
+		{
+			vorbis_comment_clear(&vc);
+			return false;
+		}
+	}
+	vorbis_comment_clear(&vc);
+
+	if (vorbis_synthesis_init(&m_vorbis->dspState, &m_vorbis->info))
+		return false;
+	m_vorbis->hasDSPState = true;
+
+	if (m_vorbis->info.channels != m_channels || m_vorbis->info.rate != demuxer.getSampleRate())
+		return false;
+
+	if (vorbis_block_init(&m_vorbis->dspState, &m_vorbis->block))
+		return false;
+	m_vorbis->hasBlock = true;
+
+	memset(&m_vorbis->op, 0, sizeof m_vorbis->op);
+
+	m_numSamples = 4096 / m_channels;
+
+	return true;
+}
+bool OpusVorbisDecoder::openOpus(const WebMDemuxer &demuxer)
+{
+	int opusErr = 0;
+	m_opus = opus_decoder_create(demuxer.getSampleRate(), m_channels, &opusErr);
+	if (!opusErr)
+	{
+		m_numSamples = demuxer.getSampleRate() * 0.06 + 0.5; //Maximum frame size (for 60 ms frame)
+		return true;
+	}
+	return false;
+}
+
+void OpusVorbisDecoder::close()
+{
+	if (m_vorbis)
+	{
+		if (m_vorbis->hasBlock)
+			vorbis_block_clear(&m_vorbis->block);
+		if (m_vorbis->hasDSPState)
+			vorbis_dsp_clear(&m_vorbis->dspState);
+		vorbis_info_clear(&m_vorbis->info);
+		delete m_vorbis;
+	}
+	if (m_opus)
+		opus_decoder_destroy(m_opus);
+}

thirdparty/libsimplewebm/OpusVorbisDecoder.hpp

+/*
+	MIT License
+
+	Copyright (c) 2016 Błażej Szczygieł
+
+	Permission is hereby granted, free of charge, to any person obtaining a copy
+	of this software and associated documentation files (the "Software"), to deal
+	in the Software without restriction, including without limitation the rights
+	to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+	copies of the Software, and to permit persons to whom the Software is
+	furnished to do so, subject to the following conditions:
+
+	The above copyright notice and this permission notice shall be included in all
+	copies or substantial portions of the Software.
+
+	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+	IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+	FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+	AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+	LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+	OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+	SOFTWARE.
+*/
+
+#ifndef OPUSVORBISDECODER_HPP
+#define OPUSVORBISDECODER_HPP
+
+#include "WebMDemuxer.hpp"
+
+struct VorbisDecoder;
+struct OpusDecoder;
+
+class OpusVorbisDecoder
+{
+	OpusVorbisDecoder(const OpusVorbisDecoder &);
+	void operator =(const OpusVorbisDecoder &);
+public:
+	OpusVorbisDecoder(const WebMDemuxer &demuxer);
+	~OpusVorbisDecoder();
+
+	bool isOpen() const;
+
+	inline int getBufferSamples() const
+	{
+		return m_numSamples;
+	}
+
+	bool getPCMS16(WebMFrame &frame, short *buffer, int &numOutSamples);
+
+private:
+	bool openVorbis(const WebMDemuxer &demuxer);
+	bool openOpus(const WebMDemuxer &demuxer);
+
+	void close();
+
+	VorbisDecoder *m_vorbis;
+	OpusDecoder *m_opus;
+	int m_numSamples;
+	int m_channels;
+
+};
+
+#endif // OPUSVORBISDECODER_HPP

thirdparty/libsimplewebm/VPXDecoder.cpp

+/*
+	MIT License
+
+	Copyright (c) 2016 Błażej Szczygieł
+
+	Permission is hereby granted, free of charge, to any person obtaining a copy
+	of this software and associated documentation files (the "Software"), to deal
+	in the Software without restriction, including without limitation the rights
+	to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+	copies of the Software, and to permit persons to whom the Software is
+	furnished to do so, subject to the following conditions:
+
+	The above copyright notice and this permission notice shall be included in all
+	copies or substantial portions of the Software.
+
+	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+	IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+	FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+	AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+	LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+	OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+	SOFTWARE.
+*/
+
+#include "VPXDecoder.hpp"
+
+#include <vpx/vpx_decoder.h>
+#include <vpx/vp8dx.h>
+
+#include <stdlib.h>
+#include <string.h>
+
+VPXDecoder::VPXDecoder(const WebMDemuxer &demuxer, unsigned threads) :
+	m_ctx(NULL),
+	m_iter(NULL),
+	m_delay(0)
+{
+	if (threads > 8)
+		threads = 8;
+	else if (threads < 1)
+		threads = 1;
+
+	const vpx_codec_dec_cfg_t codecCfg = {
+		threads,
+		0,
+		0
+	};
+	vpx_codec_iface_t *codecIface = NULL;
+
+	switch (demuxer.getVideoCodec())
+	{
+		case WebMDemuxer::VIDEO_VP8:
+			codecIface = vpx_codec_vp8_dx();
+			break;
+		case WebMDemuxer::VIDEO_VP9:
+			codecIface = vpx_codec_vp9_dx();
+			m_delay = threads - 1;
+			break;
+		default:
+			return;
+	}
+
+	m_ctx = new vpx_codec_ctx_t;
+	if (vpx_codec_dec_init(m_ctx, codecIface, &codecCfg, m_delay > 0 ? VPX_CODEC_USE_FRAME_THREADING : 0))
+	{
+		delete m_ctx;
+		m_ctx = NULL;
+	}
+}
+VPXDecoder::~VPXDecoder()
+{
+	if (m_ctx)
+	{
+		vpx_codec_destroy(m_ctx);
+		delete m_ctx;
+	}
+}
+
+bool VPXDecoder::decode(const WebMFrame &frame)
+{
+	m_iter = NULL;
+	return !vpx_codec_decode(m_ctx, frame.buffer, frame.bufferSize, NULL, 0);
+}
+VPXDecoder::IMAGE_ERROR VPXDecoder::getImage(Image &image)
+{
+	IMAGE_ERROR err = NO_FRAME;
+	if (vpx_image_t *img = vpx_codec_get_frame(m_ctx, &m_iter))
+	{
+		if ((img->fmt & VPX_IMG_FMT_PLANAR) && !(img->fmt & (VPX_IMG_FMT_HAS_ALPHA | VPX_IMG_FMT_HIGHBITDEPTH)))
+		{
+			if (img->stride[0] && img->stride[1] && img->stride[2])
+			{
+				const int uPlane = !!(img->fmt & VPX_IMG_FMT_UV_FLIP) + 1;
+				const int vPlane =  !(img->fmt & VPX_IMG_FMT_UV_FLIP) + 1;
+
+				image.w = img->d_w;
+				image.h = img->d_h;
+				image.chromaShiftW = img->x_chroma_shift;
+				image.chromaShiftH = img->y_chroma_shift;
+
+				image.planes[0] = img->planes[0];
+				image.planes[1] = img->planes[uPlane];
+				image.planes[2] = img->planes[vPlane];
+
+				image.linesize[0] = img->stride[0];
+				image.linesize[1] = img->stride[uPlane];
+				image.linesize[2] = img->stride[vPlane];
+
+				err = NO_ERROR;
+			}
+		}
+		else
+		{
+			err = UNSUPPORTED_FRAME;
+		}
+	}
+	return err;
+}
+
+/**/
+
+#if 0
+
+static inline int ceilRshift(int val, int shift)
+{
+	return (val + (1 << shift) - 1) >> shift;
+}
+
+int VPXDecoder::Image::getWidth(int plane) const
+{
+	if (!plane)
+		return w;
+	return ceilRshift(w, chromaShiftW);
+}
+int VPXDecoder::Image::getHeight(int plane) const
+{
+	if (!plane)
+		return h;
+	return ceilRshift(h, chromaShiftH);
+}
+
+#endif

thirdparty/libsimplewebm/VPXDecoder.hpp

+/*
+	MIT License
+
+	Copyright (c) 2016 Błażej Szczygieł
+
+	Permission is hereby granted, free of charge, to any person obtaining a copy
+	of this software and associated documentation files (the "Software"), to deal
+	in the Software without restriction, including without limitation the rights
+	to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+	copies of the Software, and to permit persons to whom the Software is
+	furnished to do so, subject to the following conditions:
+
+	The above copyright notice and this permission notice shall be included in all
+	copies or substantial portions of the Software.
+
+	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+	IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+	FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+	AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+	LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+	OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+	SOFTWARE.
+*/
+
+#ifndef VPXDECODER_HPP
+#define VPXDECODER_HPP
+
+#include "WebMDemuxer.hpp"
+
+struct vpx_codec_ctx;
+
+class VPXDecoder
+{
+	VPXDecoder(const VPXDecoder &);
+	void operator =(const VPXDecoder &);
+public:
+	class Image
+	{
+	public:
+#if 0
+		int getWidth(int plane) const;
+		int getHeight(int plane) const;
+#endif
+
+		int w, h;
+		int chromaShiftW, chromaShiftH;
+		unsigned char *planes[3];
+		int linesize[3];
+	};
+
+	enum IMAGE_ERROR
+	{
+		UNSUPPORTED_FRAME = -1,
+		NO_ERROR,
+		NO_FRAME
+	};
+
+	VPXDecoder(const WebMDemuxer &demuxer, unsigned threads = 1);
+	~VPXDecoder();
+
+	inline bool isOpen() const
+	{
+		return (bool)m_ctx;
+	}
+
+	inline int getFramesDelay() const
+	{
+		return m_delay;
+	}
+
+	bool decode(const WebMFrame &frame);
+	IMAGE_ERROR getImage(Image &image); //The data is NOT copied! Only 3-plane, 8-bit images are supported.
+
+private:
+	vpx_codec_ctx *m_ctx;
+	const void *m_iter;
+	int m_delay;
+};
+
+#endif // VPXDECODER_HPP

thirdparty/libsimplewebm/WebMDemuxer.cpp

+/*
+	MIT License
+
+	Copyright (c) 2016 Błażej Szczygieł
+
+	Permission is hereby granted, free of charge, to any person obtaining a copy
+	of this software and associated documentation files (the "Software"), to deal
+	in the Software without restriction, including without limitation the rights
+	to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+	copies of the Software, and to permit persons to whom the Software is
+	furnished to do so, subject to the following conditions:
+
+	The above copyright notice and this permission notice shall be included in all
+	copies or substantial portions of the Software.
+
+	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+	IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+	FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+	AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+	LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+	OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+	SOFTWARE.
+*/
+
+#include "WebMDemuxer.hpp"
+
+#include "mkvparser/mkvparser.h"
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+
+WebMFrame::WebMFrame() :
+	bufferSize(0), bufferCapacity(0),
+	buffer(NULL),
+	time(0),
+	key(false)
+{}
+WebMFrame::~WebMFrame()
+{
+	free(buffer);
+}
+
+/**/
+
+WebMDemuxer::WebMDemuxer(mkvparser::IMkvReader *reader, int videoTrack, int audioTrack) :
+	m_reader(reader),
+	m_segment(NULL),
+	m_cluster(NULL), m_block(NULL), m_blockEntry(NULL),
+	m_blockFrameIndex(0),
+	m_videoTrack(NULL), m_vCodec(NO_VIDEO),
+	m_audioTrack(NULL), m_aCodec(NO_AUDIO),
+	m_isOpen(false),
+	m_eos(false)
+{
+	long long pos = 0;
+	if (mkvparser::EBMLHeader().Parse(m_reader, pos))
+		return;
+
+	if (mkvparser::Segment::CreateInstance(m_reader, pos, m_segment))
+		return;
+
+	if (m_segment->Load() < 0)
+		return;
+
+	const mkvparser::Tracks *tracks = m_segment->GetTracks();
+	const unsigned long tracksCount = tracks->GetTracksCount();
+	int currVideoTrack = -1, currAudioTrack = -1;
+	for (unsigned long i = 0; i < tracksCount; ++i)
+	{
+		const mkvparser::Track *track = tracks->GetTrackByIndex(i);
+		if (const char *codecId = track->GetCodecId())
+		{
+			if ((!m_videoTrack || currVideoTrack != videoTrack) && track->GetType() == mkvparser::Track::kVideo)
+			{
+				if (!strcmp(codecId, "V_VP8"))
+					m_vCodec = VIDEO_VP8;
+				else if (!strcmp(codecId, "V_VP9"))
+					m_vCodec = VIDEO_VP9;
+				if (m_vCodec != NO_VIDEO)
+					m_videoTrack = static_cast<const mkvparser::VideoTrack *>(track);
+				++currVideoTrack;
+			}
+			if ((!m_audioTrack || currAudioTrack != audioTrack) && track->GetType() == mkvparser::Track::kAudio)
+			{
+				if (!strcmp(codecId, "A_VORBIS"))
+					m_aCodec = AUDIO_VORBIS;
+				else if (!strcmp(codecId, "A_OPUS"))
+					m_aCodec = AUDIO_OPUS;
+				if (m_aCodec != NO_AUDIO)
+					m_audioTrack = static_cast<const mkvparser::AudioTrack *>(track);
+				++currAudioTrack;
+			}
+		}
+	}
+	if (!m_videoTrack && !m_audioTrack)
+		return;
+
+	m_isOpen = true;
+}
+WebMDemuxer::~WebMDemuxer()
+{
+	delete m_segment;
+	delete m_reader;
+}
+
+double WebMDemuxer::getLength() const
+{
+	return m_segment->GetDuration() / 1e9;
+}
+
+WebMDemuxer::VIDEO_CODEC WebMDemuxer::getVideoCodec() const
+{
+	return m_vCodec;
+}
+int WebMDemuxer::getWidth() const
+{
+	return m_videoTrack->GetWidth();
+}
+int WebMDemuxer::getHeight() const
+{
+	return m_videoTrack->GetHeight();
+}
+
+WebMDemuxer::AUDIO_CODEC WebMDemuxer::getAudioCodec() const
+{
+	return m_aCodec;
+}
+const unsigned char *WebMDemuxer::getAudioExtradata(size_t &size) const
+{
+	return m_audioTrack->GetCodecPrivate(size);
+}
+double WebMDemuxer::getSampleRate() const
+{
+	return m_audioTrack->GetSamplingRate();
+}
+int WebMDemuxer::getChannels() const
+{
+	return m_audioTrack->GetChannels();
+}
+int WebMDemuxer::getAudioDepth() const
+{
+	return m_audioTrack->GetBitDepth();
+}
+
+bool WebMDemuxer::readFrame(WebMFrame *videoFrame, WebMFrame *audioFrame)
+{
+	const long videoTrackNumber = (videoFrame && m_videoTrack) ? m_videoTrack->GetNumber() : 0;
+	const long audioTrackNumber = (audioFrame && m_audioTrack) ? m_audioTrack->GetNumber() : 0;
+	bool blockEntryEOS = false;
+
+	if (videoFrame)
+		videoFrame->bufferSize = 0;
+	if (audioFrame)
+		audioFrame->bufferSize = 0;
+
+	if (videoTrackNumber == 0 && audioTrackNumber == 0)
+		return false;
+
+	if (m_eos)
+		return false;
+
+	if (!m_cluster)
+		m_cluster = m_segment->GetFirst();
+
+	do
+	{
+		bool getNewBlock = false;
+		long status = 0;
+		if (!m_blockEntry && !blockEntryEOS)
+		{
+			status = m_cluster->GetFirst(m_blockEntry);
+			getNewBlock = true;
+		}
+		else if (blockEntryEOS || m_blockEntry->EOS())
+		{
+			m_cluster = m_segment->GetNext(m_cluster);
+			if (!m_cluster || m_cluster->EOS())
+			{
+				m_eos = true;
+				return false;
+			}
+			status = m_cluster->GetFirst(m_blockEntry);
+			blockEntryEOS = false;
+			getNewBlock = true;
+		}
+		else if (!m_block || m_blockFrameIndex == m_block->GetFrameCount() || notSupportedTrackNumber(videoTrackNumber, audioTrackNumber))
+		{
+			status = m_cluster->GetNext(m_blockEntry, m_blockEntry);
+			if (!m_blockEntry  || m_blockEntry->EOS())
+			{
+				blockEntryEOS = true;
+				continue;
+			}
+			getNewBlock = true;
+		}
+		if (status || !m_blockEntry)
+			return false;
+		if (getNewBlock)
+		{
+			m_block = m_blockEntry->GetBlock();
+			m_blockFrameIndex = 0;
+		}
+	} while (blockEntryEOS || notSupportedTrackNumber(videoTrackNumber, audioTrackNumber));
+
+	WebMFrame *frame = NULL;
+
+	const long trackNumber = m_block->GetTrackNumber();
+	if (trackNumber == videoTrackNumber)
+		frame = videoFrame;
+	else if (trackNumber == audioTrackNumber)
+		frame = audioFrame;
+	else
+	{
+		//Should not be possible
+		assert(trackNumber == videoTrackNumber || trackNumber == audioTrackNumber);
+		return false;
+	}
+
+	const mkvparser::Block::Frame &blockFrame = m_block->GetFrame(m_blockFrameIndex++);
+	if (blockFrame.len > frame->bufferCapacity)
+	{
+		unsigned char *newBuff = (unsigned char *)realloc(frame->buffer, frame->bufferCapacity = blockFrame.len);
+		if (newBuff)
+			frame->buffer = newBuff;
+		else // Out of memory
+			return false;
+	}
+	frame->bufferSize = blockFrame.len;
+
+	frame->time = m_block->GetTime(m_cluster) / 1e9;
+	frame->key  = m_block->IsKey();
+
+	return !blockFrame.Read(m_reader, frame->buffer);
+}
+
+inline bool WebMDemuxer::notSupportedTrackNumber(long videoTrackNumber, long audioTrackNumber) const
+{
+	const long trackNumber = m_block->GetTrackNumber();
+	return (trackNumber != videoTrackNumber && trackNumber != audioTrackNumber);
+}

thirdparty/libsimplewebm/WebMDemuxer.hpp

+/*
+	MIT License
+
+	Copyright (c) 2016 Błażej Szczygieł
+
+	Permission is hereby granted, free of charge, to any person obtaining a copy
+	of this software and associated documentation files (the "Software"), to deal
+	in the Software without restriction, including without limitation the rights
+	to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+	copies of the Software, and to permit persons to whom the Software is
+	furnished to do so, subject to the following conditions:
+
+	The above copyright notice and this permission notice shall be included in all
+	copies or substantial portions of the Software.
+
+	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+	IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+	FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+	AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+	LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+	OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+	SOFTWARE.
+*/
+
+#ifndef WEBMDEMUXER_HPP
+#define WEBMDEMUXER_HPP
+
+#include <stddef.h>
+
+namespace mkvparser {
+	class IMkvReader;
+	class Segment;
+	class Cluster;
+	class Block;
+	class BlockEntry;
+	class VideoTrack;
+	class AudioTrack;
+}
+
+class WebMFrame
+{
+	WebMFrame(const WebMFrame &);
+	void operator =(const WebMFrame &);
+public:
+	WebMFrame();
+	~WebMFrame();
+
+	inline bool isValid() const
+	{
+		return bufferSize > 0;
+	}
+
+	long bufferSize, bufferCapacity;
+	unsigned char *buffer;
+	double time;
+	bool key;
+};
+
+class WebMDemuxer
+{
+	WebMDemuxer(const WebMDemuxer &);
+	void operator =(const WebMDemuxer &);
+public:
+	enum VIDEO_CODEC
+	{
+		NO_VIDEO,
+		VIDEO_VP8,
+		VIDEO_VP9
+	};
+	enum AUDIO_CODEC
+	{
+		NO_AUDIO,
+		AUDIO_VORBIS,
+		AUDIO_OPUS
+	};
+
+	WebMDemuxer(mkvparser::IMkvReader *reader, int videoTrack = 0, int audioTrack = 0);
+	~WebMDemuxer();
+
+	inline bool isOpen() const
+	{
+		return m_isOpen;
+	}
+	inline bool isEOS() const
+	{
+		return m_eos;
+	}
+
+	double getLength() const;
+
+	VIDEO_CODEC getVideoCodec() const;
+	int getWidth() const;
+	int getHeight() const;
+
+	AUDIO_CODEC getAudioCodec() const;
+	const unsigned char *getAudioExtradata(size_t &size) const; // Needed for Vorbis
+	double getSampleRate() const;
+	int getChannels() const;
+	int getAudioDepth() const;
+
+	bool readFrame(WebMFrame *videoFrame, WebMFrame *audioFrame);
+
+private:
+	inline bool notSupportedTrackNumber(long videoTrackNumber, long audioTrackNumber) const;
+
+	mkvparser::IMkvReader *m_reader;
+	mkvparser::Segment *m_segment;
+
+	const mkvparser::Cluster *m_cluster;
+	const mkvparser::Block *m_block;
+	const mkvparser::BlockEntry *m_blockEntry;
+
+	int m_blockFrameIndex;
+
+	const mkvparser::VideoTrack *m_videoTrack;
+	VIDEO_CODEC m_vCodec;
+
+	const mkvparser::AudioTrack *m_audioTrack;
+	AUDIO_CODEC m_aCodec;
+
+	bool m_isOpen;
+	bool m_eos;
+};
+
+#endif // WEBMDEMUXER_HPP

thirdparty/libsimplewebm/libwebm/AUTHORS.TXT

+# Names should be added to this file like so:
+# Name or Organization <email address>
+
+Google Inc.

thirdparty/libsimplewebm/libwebm/LICENSE.TXT

+Copyright (c) 2010, Google Inc. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+  * Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+  * Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+  * Neither the name of Google nor the names of its contributors may
+    be used to endorse or promote products derived from this software
+    without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+

thirdparty/libsimplewebm/libwebm/PATENTS.TXT

+Additional IP Rights Grant (Patents)
+------------------------------------
+
+"These implementations" means the copyrightable works that implement the WebM
+codecs distributed by Google as part of the WebM Project.
+
+Google hereby grants to you a perpetual, worldwide, non-exclusive, no-charge,
+royalty-free, irrevocable (except as stated in this section) patent license to
+make, have made, use, offer to sell, sell, import, transfer, and otherwise
+run, modify and propagate the contents of these implementations of WebM, where
+such license applies only to those patent claims, both currently owned by
+Google and acquired in the future, licensable by Google that are necessarily
+infringed by these implementations of WebM. This grant does not include claims
+that would be infringed only as a consequence of further modification of these
+implementations. If you or your agent or exclusive licensee institute or order
+or agree to the institution of patent litigation or any other patent
+enforcement activity against any entity (including a cross-claim or
+counterclaim in a lawsuit) alleging that any of these implementations of WebM
+or any code incorporated within any of these implementations of WebM
+constitute direct or contributory patent infringement, or inducement of
+patent infringement, then any patent rights granted to you under this License
+for these implementations of WebM shall terminate as of the date such
+litigation is filed.

thirdparty/libsimplewebm/libwebm/README.libvpx

+URL: https://chromium.googlesource.com/webm/libwebm
+Version: 32d5ac49414a8914ec1e1f285f3f927c6e8ec29d
+License: BSD
+License File: LICENSE.txt
+
+Description:
+libwebm is used to handle WebM container I/O.
+
+Local Changes:
+* Removed: "mkvmuxer", "hdr_util", "file_util", "mkv_reader".
+* Make "~IMkvRerader()" public.

thirdparty/libsimplewebm/libwebm/common/webmids.h

+// Copyright (c) 2012 The WebM project authors. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the LICENSE file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS.  All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+
+#ifndef COMMON_WEBMIDS_H_
+#define COMMON_WEBMIDS_H_
+
+namespace libwebm {
+
+enum MkvId {
+  kMkvEBML = 0x1A45DFA3,
+  kMkvEBMLVersion = 0x4286,
+  kMkvEBMLReadVersion = 0x42F7,
+  kMkvEBMLMaxIDLength = 0x42F2,
+  kMkvEBMLMaxSizeLength = 0x42F3,
+  kMkvDocType = 0x4282,
+  kMkvDocTypeVersion = 0x4287,
+  kMkvDocTypeReadVersion = 0x4285,
+  kMkvVoid = 0xEC,
+  kMkvSignatureSlot = 0x1B538667,
+  kMkvSignatureAlgo = 0x7E8A,
+  kMkvSignatureHash = 0x7E9A,
+  kMkvSignaturePublicKey = 0x7EA5,
+  kMkvSignature = 0x7EB5,
+  kMkvSignatureElements = 0x7E5B,
+  kMkvSignatureElementList = 0x7E7B,
+  kMkvSignedElement = 0x6532,
+  // segment
+  kMkvSegment = 0x18538067,
+  // Meta Seek Information
+  kMkvSeekHead = 0x114D9B74,
+  kMkvSeek = 0x4DBB,
+  kMkvSeekID = 0x53AB,
+  kMkvSeekPosition = 0x53AC,
+  // Segment Information
+  kMkvInfo = 0x1549A966,
+  kMkvTimecodeScale = 0x2AD7B1,
+  kMkvDuration = 0x4489,
+  kMkvDateUTC = 0x4461,
+  kMkvTitle = 0x7BA9,
+  kMkvMuxingApp = 0x4D80,
+  kMkvWritingApp = 0x5741,
+  // Cluster
+  kMkvCluster = 0x1F43B675,
+  kMkvTimecode = 0xE7,
+  kMkvPrevSize = 0xAB,
+  kMkvBlockGroup = 0xA0,
+  kMkvBlock = 0xA1,
+  kMkvBlockDuration = 0x9B,
+  kMkvReferenceBlock = 0xFB,
+  kMkvLaceNumber = 0xCC,
+  kMkvSimpleBlock = 0xA3,
+  kMkvBlockAdditions = 0x75A1,
+  kMkvBlockMore = 0xA6,
+  kMkvBlockAddID = 0xEE,
+  kMkvBlockAdditional = 0xA5,
+  kMkvDiscardPadding = 0x75A2,
+  // Track
+  kMkvTracks = 0x1654AE6B,
+  kMkvTrackEntry = 0xAE,
+  kMkvTrackNumber = 0xD7,
+  kMkvTrackUID = 0x73C5,
+  kMkvTrackType = 0x83,
+  kMkvFlagEnabled = 0xB9,
+  kMkvFlagDefault = 0x88,
+  kMkvFlagForced = 0x55AA,
+  kMkvFlagLacing = 0x9C,
+  kMkvDefaultDuration = 0x23E383,
+  kMkvMaxBlockAdditionID = 0x55EE,
+  kMkvName = 0x536E,
+  kMkvLanguage = 0x22B59C,
+  kMkvCodecID = 0x86,
+  kMkvCodecPrivate = 0x63A2,
+  kMkvCodecName = 0x258688,
+  kMkvCodecDelay = 0x56AA,
+  kMkvSeekPreRoll = 0x56BB,
+  // video
+  kMkvVideo = 0xE0,
+  kMkvFlagInterlaced = 0x9A,
+  kMkvStereoMode = 0x53B8,
+  kMkvAlphaMode = 0x53C0,
+  kMkvPixelWidth = 0xB0,
+  kMkvPixelHeight = 0xBA,
+  kMkvPixelCropBottom = 0x54AA,
+  kMkvPixelCropTop = 0x54BB,
+  kMkvPixelCropLeft = 0x54CC,
+  kMkvPixelCropRight = 0x54DD,
+  kMkvDisplayWidth = 0x54B0,
+  kMkvDisplayHeight = 0x54BA,
+  kMkvDisplayUnit = 0x54B2,
+  kMkvAspectRatioType = 0x54B3,
+  kMkvFrameRate = 0x2383E3,
+  // end video
+  // colour
+  kMkvColour = 0x55B0,
+  kMkvMatrixCoefficients = 0x55B1,
+  kMkvBitsPerChannel = 0x55B2,
+  kMkvChromaSubsamplingHorz = 0x55B3,
+  kMkvChromaSubsamplingVert = 0x55B4,
+  kMkvCbSubsamplingHorz = 0x55B5,
+  kMkvCbSubsamplingVert = 0x55B6,
+  kMkvChromaSitingHorz = 0x55B7,
+  kMkvChromaSitingVert = 0x55B8,
+  kMkvRange = 0x55B9,
+  kMkvTransferCharacteristics = 0x55BA,
+  kMkvPrimaries = 0x55BB,
+  kMkvMaxCLL = 0x55BC,
+  kMkvMaxFALL = 0x55BD,
+  // mastering metadata
+  kMkvMasteringMetadata = 0x55D0,
+  kMkvPrimaryRChromaticityX = 0x55D1,
+  kMkvPrimaryRChromaticityY = 0x55D2,
+  kMkvPrimaryGChromaticityX = 0x55D3,
+  kMkvPrimaryGChromaticityY = 0x55D4,
+  kMkvPrimaryBChromaticityX = 0x55D5,
+  kMkvPrimaryBChromaticityY = 0x55D6,
+  kMkvWhitePointChromaticityX = 0x55D7,
+  kMkvWhitePointChromaticityY = 0x55D8,
+  kMkvLuminanceMax = 0x55D9,
+  kMkvLuminanceMin = 0x55DA,
+  // end mastering metadata
+  // end colour
+  // audio
+  kMkvAudio = 0xE1,
+  kMkvSamplingFrequency = 0xB5,
+  kMkvOutputSamplingFrequency = 0x78B5,
+  kMkvChannels = 0x9F,
+  kMkvBitDepth = 0x6264,
+  // end audio
+  // ContentEncodings
+  kMkvContentEncodings = 0x6D80,
+  kMkvContentEncoding = 0x6240,
+  kMkvContentEncodingOrder = 0x5031,
+  kMkvContentEncodingScope = 0x5032,
+  kMkvContentEncodingType = 0x5033,
+  kMkvContentCompression = 0x5034,
+  kMkvContentCompAlgo = 0x4254,
+  kMkvContentCompSettings = 0x4255,
+  kMkvContentEncryption = 0x5035,
+  kMkvContentEncAlgo = 0x47E1,
+  kMkvContentEncKeyID = 0x47E2,
+  kMkvContentSignature = 0x47E3,
+  kMkvContentSigKeyID = 0x47E4,
+  kMkvContentSigAlgo = 0x47E5,
+  kMkvContentSigHashAlgo = 0x47E6,
+  kMkvContentEncAESSettings = 0x47E7,
+  kMkvAESSettingsCipherMode = 0x47E8,
+  kMkvAESSettingsCipherInitData = 0x47E9,
+  // end ContentEncodings
+  // Cueing Data
+  kMkvCues = 0x1C53BB6B,
+  kMkvCuePoint = 0xBB,
+  kMkvCueTime = 0xB3,
+  kMkvCueTrackPositions = 0xB7,
+  kMkvCueTrack = 0xF7,
+  kMkvCueClusterPosition = 0xF1,
+  kMkvCueBlockNumber = 0x5378,
+  // Chapters
+  kMkvChapters = 0x1043A770,
+  kMkvEditionEntry = 0x45B9,
+  kMkvChapterAtom = 0xB6,
+  kMkvChapterUID = 0x73C4,
+  kMkvChapterStringUID = 0x5654,
+  kMkvChapterTimeStart = 0x91,
+  kMkvChapterTimeEnd = 0x92,
+  kMkvChapterDisplay = 0x80,
+  kMkvChapString = 0x85,
+  kMkvChapLanguage = 0x437C,
+  kMkvChapCountry = 0x437E,
+  // Tags
+  kMkvTags = 0x1254C367,
+  kMkvTag = 0x7373,
+  kMkvSimpleTag = 0x67C8,
+  kMkvTagName = 0x45A3,
+  kMkvTagString = 0x4487
+};
+
+}  // namespace libwebm
+
+#endif  // COMMON_WEBMIDS_H_

thirdparty/libsimplewebm/libwebm/mkvmuxer/mkvmuxertypes.h

+// Copyright (c) 2012 The WebM project authors. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the LICENSE file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS.  All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+
+#ifndef MKVMUXER_MKVMUXERTYPES_H_
+#define MKVMUXER_MKVMUXERTYPES_H_
+
+namespace mkvmuxer {
+typedef unsigned char uint8;
+typedef short int16;
+typedef int int32;
+typedef unsigned int uint32;
+typedef long long int64;
+typedef unsigned long long uint64;
+}  // namespace mkvmuxer
+
+// Copied from Chromium basictypes.h
+// A macro to disallow the copy constructor and operator= functions
+// This should be used in the private: declarations for a class
+#define LIBWEBM_DISALLOW_COPY_AND_ASSIGN(TypeName) \
+  TypeName(const TypeName&);                       \
+  void operator=(const TypeName&)
+
+#endif  // MKVMUXER_MKVMUXERTYPES_HPP_

thirdparty/libsimplewebm/libwebm/mkvparser/mkvparser.h

+// Copyright (c) 2012 The WebM project authors. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the LICENSE file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS.  All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+#ifndef MKVPARSER_MKVPARSER_H_
+#define MKVPARSER_MKVPARSER_H_
+
+#include <stddef.h>
+
+namespace mkvparser {
+
+const int E_PARSE_FAILED = -1;
+const int E_FILE_FORMAT_INVALID = -2;
+const int E_BUFFER_NOT_FULL = -3;
+
+class IMkvReader {
+ public:
+  virtual int Read(long long pos, long len, unsigned char* buf) = 0;
+  virtual int Length(long long* total, long long* available) = 0;
+
+  virtual ~IMkvReader();
+};
+
+template <typename Type>
+Type* SafeArrayAlloc(unsigned long long num_elements,
+                     unsigned long long element_size);
+long long GetUIntLength(IMkvReader*, long long, long&);
+long long ReadUInt(IMkvReader*, long long, long&);
+long long ReadID(IMkvReader* pReader, long long pos, long& len);
+long long UnserializeUInt(IMkvReader*, long long pos, long long size);
+
+long UnserializeFloat(IMkvReader*, long long pos, long long size, double&);
+long UnserializeInt(IMkvReader*, long long pos, long long size,
+                    long long& result);
+
+long UnserializeString(IMkvReader*, long long pos, long long size, char*& str);
+
+long ParseElementHeader(IMkvReader* pReader,
+                        long long& pos,  // consume id and size fields
+                        long long stop,  // if you know size of element's parent
+                        long long& id, long long& size);
+
+bool Match(IMkvReader*, long long&, unsigned long, long long&);
+bool Match(IMkvReader*, long long&, unsigned long, unsigned char*&, size_t&);
+
+void GetVersion(int& major, int& minor, int& build, int& revision);
+
+struct EBMLHeader {
+  EBMLHeader();
+  ~EBMLHeader();
+  long long m_version;
+  long long m_readVersion;
+  long long m_maxIdLength;
+  long long m_maxSizeLength;
+  char* m_docType;
+  long long m_docTypeVersion;
+  long long m_docTypeReadVersion;
+
+  long long Parse(IMkvReader*, long long&);
+  void Init();
+};
+
+class Segment;
+class Track;
+class Cluster;
+
+class Block {
+  Block(const Block&);
+  Block& operator=(const Block&);
+
+ public:
+  const long long m_start;
+  const long long m_size;
+
+  Block(long long start, long long size, long long discard_padding);
+  ~Block();
+
+  long Parse(const Cluster*);
+
+  long long GetTrackNumber() const;
+  long long GetTimeCode(const Cluster*) const;  // absolute, but not scaled
+  long long GetTime(const Cluster*) const;  // absolute, and scaled (ns)
+  bool IsKey() const;
+  void SetKey(bool);
+  bool IsInvisible() const;
+
+  enum Lacing { kLacingNone, kLacingXiph, kLacingFixed, kLacingEbml };
+  Lacing GetLacing() const;
+
+  int GetFrameCount() const;  // to index frames: [0, count)
+
+  struct Frame {
+    long long pos;  // absolute offset
+    long len;
+
+    long Read(IMkvReader*, unsigned char*) const;
+  };
+
+  const Frame& GetFrame(int frame_index) const;
+
+  long long GetDiscardPadding() const;
+
+ private:
+  long long m_track;  // Track::Number()
+  short m_timecode;  // relative to cluster
+  unsigned char m_flags;
+
+  Frame* m_frames;
+  int m_frame_count;
+
+ protected:
+  const long long m_discard_padding;
+};
+
+class BlockEntry {
+  BlockEntry(const BlockEntry&);
+  BlockEntry& operator=(const BlockEntry&);
+
+ protected:
+  BlockEntry(Cluster*, long index);
+
+ public:
+  virtual ~BlockEntry();
+
+  bool EOS() const { return (GetKind() == kBlockEOS); }
+  const Cluster* GetCluster() const;
+  long GetIndex() const;
+  virtual const Block* GetBlock() const = 0;
+
+  enum Kind { kBlockEOS, kBlockSimple, kBlockGroup };
+  virtual Kind GetKind() const = 0;
+
+ protected:
+  Cluster* const m_pCluster;
+  const long m_index;
+};
+
+class SimpleBlock : public BlockEntry {
+  SimpleBlock(const SimpleBlock&);
+  SimpleBlock& operator=(const SimpleBlock&);
+
+ public:
+  SimpleBlock(Cluster*, long index, long long start, long long size);
+  long Parse();
+
+  Kind GetKind() const;
+  const Block* GetBlock() const;
+
+ protected:
+  Block m_block;
+};
+
+class BlockGroup : public BlockEntry {
+  BlockGroup(const BlockGroup&);
+  BlockGroup& operator=(const BlockGroup&);
+
+ public:
+  BlockGroup(Cluster*, long index,
+             long long block_start,  // absolute pos of block's payload
+             long long block_size,  // size of block's payload
+             long long prev, long long next, long long duration,
+             long long discard_padding);
+
+  long Parse();
+
+  Kind GetKind() const;
+  const Block* GetBlock() const;
+
+  long long GetPrevTimeCode() const;  // relative to block's time
+  long long GetNextTimeCode() const;  // as above
+  long long GetDurationTimeCode() const;
+
+ private:
+  Block m_block;
+  const long long m_prev;
+  const long long m_next;
+  const long long m_duration;
+};
+
+///////////////////////////////////////////////////////////////
+// ContentEncoding element
+// Elements used to describe if the track data has been encrypted or
+// compressed with zlib or header stripping.
+class ContentEncoding {
+ public:
+  enum { kCTR = 1 };
+
+  ContentEncoding();
+  ~ContentEncoding();
+
+  // ContentCompression element names
+  struct ContentCompression {
+    ContentCompression();
+    ~ContentCompression();
+
+    unsigned long long algo;
+    unsigned char* settings;
+    long long settings_len;
+  };
+
+  // ContentEncAESSettings element names
+  struct ContentEncAESSettings {
+    ContentEncAESSettings() : cipher_mode(kCTR) {}
+    ~ContentEncAESSettings() {}
+
+    unsigned long long cipher_mode;
+  };
+
+  // ContentEncryption element names
+  struct ContentEncryption {
+    ContentEncryption();
+    ~ContentEncryption();
+
+    unsigned long long algo;
+    unsigned char* key_id;
+    long long key_id_len;
+    unsigned char* signature;
+    long long signature_len;
+    unsigned char* sig_key_id;
+    long long sig_key_id_len;
+    unsigned long long sig_algo;
+    unsigned long long sig_hash_algo;
+
+    ContentEncAESSettings aes_settings;
+  };
+
+  // Returns ContentCompression represented by |idx|. Returns NULL if |idx|
+  // is out of bounds.
+  const ContentCompression* GetCompressionByIndex(unsigned long idx) const;
+
+  // Returns number of ContentCompression elements in this ContentEncoding
+  // element.
+  unsigned long GetCompressionCount() const;
+
+  // Parses the ContentCompression element from |pReader|. |start| is the
+  // starting offset of the ContentCompression payload. |size| is the size in
+  // bytes of the ContentCompression payload. |compression| is where the parsed
+  // values will be stored.
+  long ParseCompressionEntry(long long start, long long size,
+                             IMkvReader* pReader,
+                             ContentCompression* compression);
+
+  // Returns ContentEncryption represented by |idx|. Returns NULL if |idx|
+  // is out of bounds.
+  const ContentEncryption* GetEncryptionByIndex(unsigned long idx) const;
+
+  // Returns number of ContentEncryption elements in this ContentEncoding
+  // element.
+  unsigned long GetEncryptionCount() const;
+
+  // Parses the ContentEncAESSettings element from |pReader|. |start| is the
+  // starting offset of the ContentEncAESSettings payload. |size| is the
+  // size in bytes of the ContentEncAESSettings payload. |encryption| is
+  // where the parsed values will be stored.
+  long ParseContentEncAESSettingsEntry(long long start, long long size,
+                                       IMkvReader* pReader,
+                                       ContentEncAESSettings* aes);
+
+  // Parses the ContentEncoding element from |pReader|. |start| is the
+  // starting offset of the ContentEncoding payload. |size| is the size in
+  // bytes of the ContentEncoding payload. Returns true on success.
+  long ParseContentEncodingEntry(long long start, long long size,
+                                 IMkvReader* pReader);
+
+  // Parses the ContentEncryption element from |pReader|. |start| is the
+  // starting offset of the ContentEncryption payload. |size| is the size in
+  // bytes of the ContentEncryption payload. |encryption| is where the parsed
+  // values will be stored.
+  long ParseEncryptionEntry(long long start, long long size,
+                            IMkvReader* pReader, ContentEncryption* encryption);
+
+  unsigned long long encoding_order() const { return encoding_order_; }
+  unsigned long long encoding_scope() const { return encoding_scope_; }
+  unsigned long long encoding_type() const { return encoding_type_; }
+
+ private:
+  // Member variables for list of ContentCompression elements.
+  ContentCompression** compression_entries_;
+  ContentCompression** compression_entries_end_;
+
+  // Member variables for list of ContentEncryption elements.
+  ContentEncryption** encryption_entries_;
+  ContentEncryption** encryption_entries_end_;
+
+  // ContentEncoding element names
+  unsigned long long encoding_order_;
+  unsigned long long encoding_scope_;
+  unsigned long long encoding_type_;
+
+  // LIBWEBM_DISALLOW_COPY_AND_ASSIGN(ContentEncoding);
+  ContentEncoding(const ContentEncoding&);
+  ContentEncoding& operator=(const ContentEncoding&);
+};
+
+class Track {
+  Track(const Track&);
+  Track& operator=(const Track&);
+
+ public:
+  class Info;
+  static long Create(Segment*, const Info&, long long element_start,
+                     long long element_size, Track*&);
+
+  enum Type { kVideo = 1, kAudio = 2, kSubtitle = 0x11, kMetadata = 0x21 };
+
+  Segment* const m_pSegment;
+  const long long m_element_start;
+  const long long m_element_size;
+  virtual ~Track();
+
+  long GetType() const;
+  long GetNumber() const;
+  unsigned long long GetUid() const;
+  const char* GetNameAsUTF8() const;
+  const char* GetLanguage() const;
+  const char* GetCodecNameAsUTF8() const;
+  const char* GetCodecId() const;
+  const unsigned char* GetCodecPrivate(size_t&) const;
+  bool GetLacing() const;
+  unsigned long long GetDefaultDuration() const;
+  unsigned long long GetCodecDelay() const;
+  unsigned long long GetSeekPreRoll() const;
+
+  const BlockEntry* GetEOS() const;
+
+  struct Settings {
+    long long start;
+    long long size;
+  };
+
+  class Info {
+   public:
+    Info();
+    ~Info();
+    int Copy(Info&) const;
+    void Clear();
+    long type;
+    long number;
+    unsigned long long uid;
+    unsigned long long defaultDuration;
+    unsigned long long codecDelay;
+    unsigned long long seekPreRoll;
+    char* nameAsUTF8;
+    char* language;
+    char* codecId;
+    char* codecNameAsUTF8;
+    unsigned char* codecPrivate;
+    size_t codecPrivateSize;
+    bool lacing;
+    Settings settings;
+
+   private:
+    Info(const Info&);
+    Info& operator=(const Info&);
+    int CopyStr(char* Info::*str, Info&) const;
+  };
+
+  long GetFirst(const BlockEntry*&) const;
+  long GetNext(const BlockEntry* pCurr, const BlockEntry*& pNext) const;
+  virtual bool VetEntry(const BlockEntry*) const;
+  virtual long Seek(long long time_ns, const BlockEntry*&) const;
+
+  const ContentEncoding* GetContentEncodingByIndex(unsigned long idx) const;
+  unsigned long GetContentEncodingCount() const;
+
+  long ParseContentEncodingsEntry(long long start, long long size);
+
+ protected:
+  Track(Segment*, long long element_start, long long element_size);
+
+  Info m_info;
+
+  class EOSBlock : public BlockEntry {
+   public:
+    EOSBlock();
+
+    Kind GetKind() const;
+    const Block* GetBlock() const;
+  };
+
+  EOSBlock m_eos;
+
+ private:
+  ContentEncoding** content_encoding_entries_;
+  ContentEncoding** content_encoding_entries_end_;
+};
+
+struct PrimaryChromaticity {
+  PrimaryChromaticity() : x(0), y(0) {}
+  ~PrimaryChromaticity() {}
+  static bool Parse(IMkvReader* reader, long long read_pos,
+                    long long value_size, bool is_x,
+                    PrimaryChromaticity** chromaticity);
+  float x;
+  float y;
+};
+
+struct MasteringMetadata {
+  static const float kValueNotPresent;
+
+  MasteringMetadata()
+      : r(NULL),
+        g(NULL),
+        b(NULL),
+        white_point(NULL),
+        luminance_max(kValueNotPresent),
+        luminance_min(kValueNotPresent) {}
+  ~MasteringMetadata() {
+    delete r;
+    delete g;
+    delete b;
+    delete white_point;
+  }
+
+  static bool Parse(IMkvReader* reader, long long element_start,
+                    long long element_size,
+                    MasteringMetadata** mastering_metadata);
+
+  PrimaryChromaticity* r;
+  PrimaryChromaticity* g;
+  PrimaryChromaticity* b;
+  PrimaryChromaticity* white_point;
+  float luminance_max;
+  float luminance_min;
+};
+
+struct Colour {
+  static const long long kValueNotPresent;
+
+  // Unless otherwise noted all values assigned upon construction are the
+  // equivalent of unspecified/default.
+  Colour()
+      : matrix_coefficients(kValueNotPresent),
+        bits_per_channel(kValueNotPresent),
+        chroma_subsampling_horz(kValueNotPresent),
+        chroma_subsampling_vert(kValueNotPresent),
+        cb_subsampling_horz(kValueNotPresent),
+        cb_subsampling_vert(kValueNotPresent),
+        chroma_siting_horz(kValueNotPresent),
+        chroma_siting_vert(kValueNotPresent),
+        range(kValueNotPresent),
+        transfer_characteristics(kValueNotPresent),
+        primaries(kValueNotPresent),
+        max_cll(kValueNotPresent),
+        max_fall(kValueNotPresent),
+        mastering_metadata(NULL) {}
+  ~Colour() {
+    delete mastering_metadata;
+    mastering_metadata = NULL;
+  }
+
+  static bool Parse(IMkvReader* reader, long long element_start,
+                    long long element_size, Colour** colour);
+
+  long long matrix_coefficients;
+  long long bits_per_channel;
+  long long chroma_subsampling_horz;
+  long long chroma_subsampling_vert;
+  long long cb_subsampling_horz;
+  long long cb_subsampling_vert;
+  long long chroma_siting_horz;
+  long long chroma_siting_vert;
+  long long range;
+  long long transfer_characteristics;
+  long long primaries;
+  long long max_cll;
+  long long max_fall;
+
+  MasteringMetadata* mastering_metadata;
+};
+
+class VideoTrack : public Track {
+  VideoTrack(const VideoTrack&);
+  VideoTrack& operator=(const VideoTrack&);
+
+  VideoTrack(Segment*, long long element_start, long long element_size);
+
+ public:
+  virtual ~VideoTrack();
+  static long Parse(Segment*, const Info&, long long element_start,
+                    long long element_size, VideoTrack*&);
+
+  long long GetWidth() const;
+  long long GetHeight() const;
+  long long GetDisplayWidth() const;
+  long long GetDisplayHeight() const;
+  long long GetDisplayUnit() const;
+  long long GetStereoMode() const;
+  double GetFrameRate() const;
+
+  bool VetEntry(const BlockEntry*) const;
+  long Seek(long long time_ns, const BlockEntry*&) const;
+
+  Colour* GetColour() const;
+
+ private:
+  long long m_width;
+  long long m_height;
+  long long m_display_width;
+  long long m_display_height;
+  long long m_display_unit;
+  long long m_stereo_mode;
+
+  double m_rate;
+
+  Colour* m_colour;
+};
+
+class AudioTrack : public Track {
+  AudioTrack(const AudioTrack&);
+  AudioTrack& operator=(const AudioTrack&);
+
+  AudioTrack(Segment*, long long element_start, long long element_size);
+
+ public:
+  static long Parse(Segment*, const Info&, long long element_start,
+                    long long element_size, AudioTrack*&);
+
+  double GetSamplingRate() const;
+  long long GetChannels() const;
+  long long GetBitDepth() const;
+
+ private:
+  double m_rate;
+  long long m_channels;
+  long long m_bitDepth;
+};
+
+class Tracks {
+  Tracks(const Tracks&);
+  Tracks& operator=(const Tracks&);
+
+ public:
+  Segment* const m_pSegment;
+  const long long m_start;
+  const long long m_size;
+  const long long m_element_start;
+  const long long m_element_size;
+
+  Tracks(Segment*, long long start, long long size, long long element_start,
+         long long element_size);
+
+  ~Tracks();
+
+  long Parse();
+
+  unsigned long GetTracksCount() const;
+
+  const Track* GetTrackByNumber(long tn) const;
+  const Track* GetTrackByIndex(unsigned long idx) const;
+
+ private:
+  Track** m_trackEntries;
+  Track** m_trackEntriesEnd;
+
+  long ParseTrackEntry(long long payload_start, long long payload_size,
+                       long long element_start, long long element_size,
+                       Track*&) const;
+};
+
+class Chapters {
+  Chapters(const Chapters&);
+  Chapters& operator=(const Chapters&);
+
+ public:
+  Segment* const m_pSegment;
+  const long long m_start;
+  const long long m_size;
+  const long long m_element_start;
+  const long long m_element_size;
+
+  Chapters(Segment*, long long payload_start, long long payload_size,
+           long long element_start, long long element_size);
+
+  ~Chapters();
+
+  long Parse();
+
+  class Atom;
+  class Edition;
+
+  class Display {
+    friend class Atom;
+    Display();
+    Display(const Display&);
+    ~Display();
+    Display& operator=(const Display&);
+
+   public:
+    const char* GetString() const;
+    const char* GetLanguage() const;
+    const char* GetCountry() const;
+
+   private:
+    void Init();
+    void ShallowCopy(Display&) const;
+    void Clear();
+    long Parse(IMkvReader*, long long pos, long long size);
+
+    char* m_string;
+    char* m_language;
+    char* m_country;
+  };
+
+  class Atom {
+    friend class Edition;
+    Atom();
+    Atom(const Atom&);
+    ~Atom();
+    Atom& operator=(const Atom&);
+
+   public:
+    unsigned long long GetUID() const;
+    const char* GetStringUID() const;
+
+    long long GetStartTimecode() const;
+    long long GetStopTimecode() const;
+
+    long long GetStartTime(const Chapters*) const;
+    long long GetStopTime(const Chapters*) const;
+
+    int GetDisplayCount() const;
+    const Display* GetDisplay(int index) const;
+
+   private:
+    void Init();
+    void ShallowCopy(Atom&) const;
+    void Clear();
+    long Parse(IMkvReader*, long long pos, long long size);
+    static long long GetTime(const Chapters*, long long timecode);
+
+    long ParseDisplay(IMkvReader*, long long pos, long long size);
+    bool ExpandDisplaysArray();
+
+    char* m_string_uid;
+    unsigned long long m_uid;
+    long long m_start_timecode;
+    long long m_stop_timecode;
+
+    Display* m_displays;
+    int m_displays_size;
+    int m_displays_count;
+  };
+
+  class Edition {
+    friend class Chapters;
+    Edition();
+    Edition(const Edition&);
+    ~Edition();
+    Edition& operator=(const Edition&);
+
+   public:
+    int GetAtomCount() const;
+    const Atom* GetAtom(int index) const;
+
+   private:
+    void Init();
+    void ShallowCopy(Edition&) const;
+    void Clear();
+    long Parse(IMkvReader*, long long pos, long long size);
+
+    long ParseAtom(IMkvReader*, long long pos, long long size);
+    bool ExpandAtomsArray();
+
+    Atom* m_atoms;
+    int m_atoms_size;
+    int m_atoms_count;
+  };
+
+  int GetEditionCount() const;
+  const Edition* GetEdition(int index) const;
+
+ private:
+  long ParseEdition(long long pos, long long size);
+  bool ExpandEditionsArray();
+
+  Edition* m_editions;
+  int m_editions_size;
+  int m_editions_count;
+};
+
+class Tags {
+  Tags(const Tags&);
+  Tags& operator=(const Tags&);
+
+ public:
+  Segment* const m_pSegment;
+  const long long m_start;
+  const long long m_size;
+  const long long m_element_start;
+  const long long m_element_size;
+
+  Tags(Segment*, long long payload_start, long long payload_size,
+       long long element_start, long long element_size);
+
+  ~Tags();
+
+  long Parse();
+
+  class Tag;
+  class SimpleTag;
+
+  class SimpleTag {
+    friend class Tag;
+    SimpleTag();
+    SimpleTag(const SimpleTag&);
+    ~SimpleTag();
+    SimpleTag& operator=(const SimpleTag&);
+
+   public:
+    const char* GetTagName() const;
+    const char* GetTagString() const;
+
+   private:
+    void Init();
+    void ShallowCopy(SimpleTag&) const;
+    void Clear();
+    long Parse(IMkvReader*, long long pos, long long size);
+
+    char* m_tag_name;
+    char* m_tag_string;
+  };
+
+  class Tag {
+    friend class Tags;
+    Tag();
+    Tag(const Tag&);
+    ~Tag();
+    Tag& operator=(const Tag&);
+
+   public:
+    int GetSimpleTagCount() const;
+    const SimpleTag* GetSimpleTag(int index) const;
+
+   private:
+    void Init();
+    void ShallowCopy(Tag&) const;
+    void Clear();
+    long Parse(IMkvReader*, long long pos, long long size);
+
+    long ParseSimpleTag(IMkvReader*, long long pos, long long size);
+    bool ExpandSimpleTagsArray();
+
+    SimpleTag* m_simple_tags;
+    int m_simple_tags_size;
+    int m_simple_tags_count;
+  };
+
+  int GetTagCount() const;
+  const Tag* GetTag(int index) const;
+
+ private:
+  long ParseTag(long long pos, long long size);
+  bool ExpandTagsArray();
+
+  Tag* m_tags;
+  int m_tags_size;
+  int m_tags_count;
+};
+
+class SegmentInfo {
+  SegmentInfo(const SegmentInfo&);
+  SegmentInfo& operator=(const SegmentInfo&);
+
+ public:
+  Segment* const m_pSegment;
+  const long long m_start;
+  const long long m_size;
+  const long long m_element_start;
+  const long long m_element_size;
+
+  SegmentInfo(Segment*, long long start, long long size,
+              long long element_start, long long element_size);
+
+  ~SegmentInfo();
+
+  long Parse();
+
+  long long GetTimeCodeScale() const;
+  long long GetDuration() const;  // scaled
+  const char* GetMuxingAppAsUTF8() const;
+  const char* GetWritingAppAsUTF8() const;
+  const char* GetTitleAsUTF8() const;
+
+ private:
+  long long m_timecodeScale;
+  double m_duration;
+  char* m_pMuxingAppAsUTF8;
+  char* m_pWritingAppAsUTF8;
+  char* m_pTitleAsUTF8;
+};
+
+class SeekHead {
+  SeekHead(const SeekHead&);
+  SeekHead& operator=(const SeekHead&);
+
+ public:
+  Segment* const m_pSegment;
+  const long long m_start;
+  const long long m_size;
+  const long long m_element_start;
+  const long long m_element_size;
+
+  SeekHead(Segment*, long long start, long long size, long long element_start,
+           long long element_size);
+
+  ~SeekHead();
+
+  long Parse();
+
+  struct Entry {
+    // the SeekHead entry payload
+    long long id;
+    long long pos;
+
+    // absolute pos of SeekEntry ID
+    long long element_start;
+
+    // SeekEntry ID size + size size + payload
+    long long element_size;
+  };
+
+  int GetCount() const;
+  const Entry* GetEntry(int idx) const;
+
+  struct VoidElement {
+    // absolute pos of Void ID
+    long long element_start;
+
+    // ID size + size size + payload size
+    long long element_size;
+  };
+
+  int GetVoidElementCount() const;
+  const VoidElement* GetVoidElement(int idx) const;
+
+ private:
+  Entry* m_entries;
+  int m_entry_count;
+
+  VoidElement* m_void_elements;
+  int m_void_element_count;
+
+  static bool ParseEntry(IMkvReader*,
+                         long long pos,  // payload
+                         long long size, Entry*);
+};
+
+class Cues;
+class CuePoint {
+  friend class Cues;
+
+  CuePoint(long, long long);
+  ~CuePoint();
+
+  CuePoint(const CuePoint&);
+  CuePoint& operator=(const CuePoint&);
+
+ public:
+  long long m_element_start;
+  long long m_element_size;
+
+  bool Load(IMkvReader*);
+
+  long long GetTimeCode() const;  // absolute but unscaled
+  long long GetTime(const Segment*) const;  // absolute and scaled (ns units)
+
+  struct TrackPosition {
+    long long m_track;
+    long long m_pos;  // of cluster
+    long long m_block;
+    // codec_state  //defaults to 0
+    // reference = clusters containing req'd referenced blocks
+    //  reftime = timecode of the referenced block
+
+    bool Parse(IMkvReader*, long long, long long);
+  };
+
+  const TrackPosition* Find(const Track*) const;
+
+ private:
+  const long m_index;
+  long long m_timecode;
+  TrackPosition* m_track_positions;
+  size_t m_track_positions_count;
+};
+
+class Cues {
+  friend class Segment;
+
+  Cues(Segment*, long long start, long long size, long long element_start,
+       long long element_size);
+  ~Cues();
+
+  Cues(const Cues&);
+  Cues& operator=(const Cues&);
+
+ public:
+  Segment* const m_pSegment;
+  const long long m_start;
+  const long long m_size;
+  const long long m_element_start;
+  const long long m_element_size;
+
+  bool Find(  // lower bound of time_ns
+      long long time_ns, const Track*, const CuePoint*&,
+      const CuePoint::TrackPosition*&) const;
+
+  const CuePoint* GetFirst() const;
+  const CuePoint* GetLast() const;
+  const CuePoint* GetNext(const CuePoint*) const;
+
+  const BlockEntry* GetBlock(const CuePoint*,
+                             const CuePoint::TrackPosition*) const;
+
+  bool LoadCuePoint() const;
+  long GetCount() const;  // loaded only
+  // long GetTotal() const;  //loaded + preloaded
+  bool DoneParsing() const;
+
+ private:
+  bool Init() const;
+  bool PreloadCuePoint(long&, long long) const;
+
+  mutable CuePoint** m_cue_points;
+  mutable long m_count;
+  mutable long m_preload_count;
+  mutable long long m_pos;
+};
+
+class Cluster {
+  friend class Segment;
+
+  Cluster(const Cluster&);
+  Cluster& operator=(const Cluster&);
+
+ public:
+  Segment* const m_pSegment;
+
+ public:
+  static Cluster* Create(Segment*,
+                         long index,  // index in segment
+                         long long off);  // offset relative to segment
+  // long long element_size);
+
+  Cluster();  // EndOfStream
+  ~Cluster();
+
+  bool EOS() const;
+
+  long long GetTimeCode() const;  // absolute, but not scaled
+  long long GetTime() const;  // absolute, and scaled (nanosecond units)
+  long long GetFirstTime() const;  // time (ns) of first (earliest) block
+  long long GetLastTime() const;  // time (ns) of last (latest) block
+
+  long GetFirst(const BlockEntry*&) const;
+  long GetLast(const BlockEntry*&) const;
+  long GetNext(const BlockEntry* curr, const BlockEntry*& next) const;
+
+  const BlockEntry* GetEntry(const Track*, long long ns = -1) const;
+  const BlockEntry* GetEntry(const CuePoint&,
+                             const CuePoint::TrackPosition&) const;
+  // const BlockEntry* GetMaxKey(const VideoTrack*) const;
+
+  //    static bool HasBlockEntries(const Segment*, long long);
+
+  static long HasBlockEntries(const Segment*, long long idoff, long long& pos,
+                              long& size);
+
+  long GetEntryCount() const;
+
+  long Load(long long& pos, long& size) const;
+
+  long Parse(long long& pos, long& size) const;
+  long GetEntry(long index, const mkvparser::BlockEntry*&) const;
+
+ protected:
+  Cluster(Segment*, long index, long long element_start);
+  // long long element_size);
+
+ public:
+  const long long m_element_start;
+  long long GetPosition() const;  // offset relative to segment
+
+  long GetIndex() const;
+  long long GetElementSize() const;
+  // long long GetPayloadSize() const;
+
+  // long long Unparsed() const;
+
+ private:
+  long m_index;
+  mutable long long m_pos;
+  // mutable long long m_size;
+  mutable long long m_element_size;
+  mutable long long m_timecode;
+  mutable BlockEntry** m_entries;
+  mutable long m_entries_size;
+  mutable long m_entries_count;
+
+  long ParseSimpleBlock(long long, long long&, long&);
+  long ParseBlockGroup(long long, long long&, long&);
+
+  long CreateBlock(long long id, long long pos, long long size,
+                   long long discard_padding);
+  long CreateBlockGroup(long long start_offset, long long size,
+                        long long discard_padding);
+  long CreateSimpleBlock(long long, long long);
+};
+
+class Segment {
+  friend class Cues;
+  friend class Track;
+  friend class VideoTrack;
+
+  Segment(const Segment&);
+  Segment& operator=(const Segment&);
+
+ private:
+  Segment(IMkvReader*, long long elem_start,
+          // long long elem_size,
+          long long pos, long long size);
+
+ public:
+  IMkvReader* const m_pReader;
+  const long long m_element_start;
+  // const long long m_element_size;
+  const long long m_start;  // posn of segment payload
+  const long long m_size;  // size of segment payload
+  Cluster m_eos;  // TODO: make private?
+
+  static long long CreateInstance(IMkvReader*, long long, Segment*&);
+  ~Segment();
+
+  long Load();  // loads headers and all clusters
+
+  // for incremental loading
+  // long long Unparsed() const;
+  bool DoneParsing() const;
+  long long ParseHeaders();  // stops when first cluster is found
+  // long FindNextCluster(long long& pos, long& size) const;
+  long LoadCluster(long long& pos, long& size);  // load one cluster
+  long LoadCluster();
+
+  long ParseNext(const Cluster* pCurr, const Cluster*& pNext, long long& pos,
+                 long& size);
+
+  const SeekHead* GetSeekHead() const;
+  const Tracks* GetTracks() const;
+  const SegmentInfo* GetInfo() const;
+  const Cues* GetCues() const;
+  const Chapters* GetChapters() const;
+  const Tags* GetTags() const;
+
+  long long GetDuration() const;
+
+  unsigned long GetCount() const;
+  const Cluster* GetFirst() const;
+  const Cluster* GetLast() const;
+  const Cluster* GetNext(const Cluster*);
+
+  const Cluster* FindCluster(long long time_nanoseconds) const;
+  // const BlockEntry* Seek(long long time_nanoseconds, const Track*) const;
+
+  const Cluster* FindOrPreloadCluster(long long pos);
+
+  long ParseCues(long long cues_off,  // offset relative to start of segment
+                 long long& parse_pos, long& parse_len);
+
+ private:
+  long long m_pos;  // absolute file posn; what has been consumed so far
+  Cluster* m_pUnknownSize;
+
+  SeekHead* m_pSeekHead;
+  SegmentInfo* m_pInfo;
+  Tracks* m_pTracks;
+  Cues* m_pCues;
+  Chapters* m_pChapters;
+  Tags* m_pTags;
+  Cluster** m_clusters;
+  long m_clusterCount;  // number of entries for which m_index >= 0
+  long m_clusterPreloadCount;  // number of entries for which m_index < 0
+  long m_clusterSize;  // array size
+
+  long DoLoadCluster(long long&, long&);
+  long DoLoadClusterUnknownSize(long long&, long&);
+  long DoParseNext(const Cluster*&, long long&, long&);
+
+  bool AppendCluster(Cluster*);
+  bool PreloadCluster(Cluster*, ptrdiff_t);
+
+  // void ParseSeekHead(long long pos, long long size);
+  // void ParseSeekEntry(long long pos, long long size);
+  // void ParseCues(long long);
+
+  const BlockEntry* GetBlock(const CuePoint&, const CuePoint::TrackPosition&);
+};
+
+}  // namespace mkvparser
+
+inline long mkvparser::Segment::LoadCluster() {
+  long long pos;
+  long size;
+
+  return LoadCluster(pos, size);
+}
+
+#endif  // MKVPARSER_MKVPARSER_H_