1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/content/media/webm/EbmlComposer.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,212 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-*/
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this file,
1.7 + * You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +#include "EbmlComposer.h"
1.10 +#include "libmkv/EbmlIDs.h"
1.11 +#include "libmkv/EbmlWriter.h"
1.12 +#include "libmkv/WebMElement.h"
1.13 +#include "prtime.h"
1.14 +
1.15 +namespace mozilla {
1.16 +
1.17 +// Timecode scale in nanoseconds
1.18 +static const unsigned long TIME_CODE_SCALE = 1000000;
1.19 +// The WebM header size without audio CodecPrivateData
1.20 +static const int32_t DEFAULT_HEADER_SIZE = 1024;
1.21 +
1.22 +void EbmlComposer::GenerateHeader()
1.23 +{
1.24 + // Write the EBML header.
1.25 + EbmlGlobal ebml;
1.26 + // The WEbM header default size usually smaller than 1k.
1.27 + nsAutoArrayPtr<uint8_t> buffer(new uint8_t[DEFAULT_HEADER_SIZE +
1.28 + mCodecPrivateData.Length()]);
1.29 + ebml.buf = buffer.get();
1.30 + ebml.offset = 0;
1.31 + writeHeader(&ebml);
1.32 + {
1.33 + EbmlLoc segEbmlLoc, ebmlLocseg, ebmlLoc;
1.34 + Ebml_StartSubElement(&ebml, &segEbmlLoc, Segment);
1.35 + {
1.36 + Ebml_StartSubElement(&ebml, &ebmlLocseg, SeekHead);
1.37 + // Todo: We don't know the exact sizes of encoded data and
1.38 + // ignore this section.
1.39 + Ebml_EndSubElement(&ebml, &ebmlLocseg);
1.40 + writeSegmentInformation(&ebml, &ebmlLoc, TIME_CODE_SCALE, 0);
1.41 + {
1.42 + EbmlLoc trackLoc;
1.43 + Ebml_StartSubElement(&ebml, &trackLoc, Tracks);
1.44 + {
1.45 + // Video
1.46 + if (mWidth > 0 && mHeight > 0) {
1.47 + writeVideoTrack(&ebml, 0x1, 0, "V_VP8",
1.48 + mWidth, mHeight,
1.49 + mDisplayWidth, mDisplayHeight, mFrameRate);
1.50 + }
1.51 + // Audio
1.52 + if (mCodecPrivateData.Length() > 0) {
1.53 + writeAudioTrack(&ebml, 0x2, 0x0, "A_VORBIS", mSampleFreq,
1.54 + mChannels, mCodecPrivateData.Elements(),
1.55 + mCodecPrivateData.Length());
1.56 + }
1.57 + }
1.58 + Ebml_EndSubElement(&ebml, &trackLoc);
1.59 + }
1.60 + }
1.61 + // The Recording length is unknown and
1.62 + // ignore write the whole Segment element size
1.63 + }
1.64 + MOZ_ASSERT(ebml.offset <= DEFAULT_HEADER_SIZE + mCodecPrivateData.Length(),
1.65 + "write more data > EBML_BUFFER_SIZE");
1.66 + auto block = mClusterBuffs.AppendElement();
1.67 + block->SetLength(ebml.offset);
1.68 + memcpy(block->Elements(), ebml.buf, ebml.offset);
1.69 + mFlushState |= FLUSH_METADATA;
1.70 +}
1.71 +
1.72 +void EbmlComposer::FinishMetadata()
1.73 +{
1.74 + if (mFlushState & FLUSH_METADATA) {
1.75 + // We don't remove the first element of mClusterBuffs because the
1.76 + // |mClusterHeaderIndex| may have value.
1.77 + mClusterCanFlushBuffs.AppendElement()->SwapElements(mClusterBuffs[0]);
1.78 + mFlushState &= ~FLUSH_METADATA;
1.79 + }
1.80 +}
1.81 +
1.82 +void EbmlComposer::FinishCluster()
1.83 +{
1.84 + FinishMetadata();
1.85 + if (!(mFlushState & FLUSH_CLUSTER)) {
1.86 + // No completed cluster available.
1.87 + return;
1.88 + }
1.89 +
1.90 + MOZ_ASSERT(mClusterLengthLoc > 0);
1.91 + EbmlGlobal ebml;
1.92 + EbmlLoc ebmlLoc;
1.93 + ebmlLoc.offset = mClusterLengthLoc;
1.94 + ebml.offset = mClusterBuffs[mClusterHeaderIndex].Length();
1.95 + ebml.buf = mClusterBuffs[mClusterHeaderIndex].Elements();
1.96 + Ebml_EndSubElement(&ebml, &ebmlLoc);
1.97 + // Move the mClusterBuffs data from mClusterHeaderIndex that we can skip
1.98 + // the metadata and the rest P-frames after ContainerWriter::FLUSH_NEEDED.
1.99 + for (uint32_t i = mClusterHeaderIndex; i < mClusterBuffs.Length(); i++) {
1.100 + mClusterCanFlushBuffs.AppendElement()->SwapElements(mClusterBuffs[i]);
1.101 + }
1.102 +
1.103 + mClusterHeaderIndex = 0;
1.104 + mClusterLengthLoc = 0;
1.105 + mClusterBuffs.Clear();
1.106 + mFlushState &= ~FLUSH_CLUSTER;
1.107 +}
1.108 +
1.109 +void
1.110 +EbmlComposer::WriteSimpleBlock(EncodedFrame* aFrame)
1.111 +{
1.112 + EbmlGlobal ebml;
1.113 + ebml.offset = 0;
1.114 +
1.115 + if (aFrame->GetFrameType() == EncodedFrame::FrameType::VP8_I_FRAME) {
1.116 + FinishCluster();
1.117 + }
1.118 +
1.119 + auto block = mClusterBuffs.AppendElement();
1.120 + block->SetLength(aFrame->GetFrameData().Length() + DEFAULT_HEADER_SIZE);
1.121 + ebml.buf = block->Elements();
1.122 +
1.123 + if (aFrame->GetFrameType() == EncodedFrame::FrameType::VP8_I_FRAME) {
1.124 + EbmlLoc ebmlLoc;
1.125 + Ebml_StartSubElement(&ebml, &ebmlLoc, Cluster);
1.126 + MOZ_ASSERT(mClusterBuffs.Length() > 0);
1.127 + // current cluster header array index
1.128 + mClusterHeaderIndex = mClusterBuffs.Length() - 1;
1.129 + mClusterLengthLoc = ebmlLoc.offset;
1.130 + mClusterTimecode = aFrame->GetTimeStamp() / PR_USEC_PER_MSEC;
1.131 + Ebml_SerializeUnsigned(&ebml, Timecode, mClusterTimecode);
1.132 + mFlushState |= FLUSH_CLUSTER;
1.133 + }
1.134 +
1.135 + if (aFrame->GetFrameType() != EncodedFrame::FrameType::VORBIS_AUDIO_FRAME) {
1.136 + short timeCode = aFrame->GetTimeStamp() / PR_USEC_PER_MSEC
1.137 + - mClusterTimecode;
1.138 + writeSimpleBlock(&ebml, 0x1, timeCode, aFrame->GetFrameType() ==
1.139 + EncodedFrame::FrameType::VP8_I_FRAME,
1.140 + 0, 0, (unsigned char*)aFrame->GetFrameData().Elements(),
1.141 + aFrame->GetFrameData().Length());
1.142 + } else {
1.143 + writeSimpleBlock(&ebml, 0x2, 0, false,
1.144 + 0, 0, (unsigned char*)aFrame->GetFrameData().Elements(),
1.145 + aFrame->GetFrameData().Length());
1.146 + }
1.147 + MOZ_ASSERT(ebml.offset <= DEFAULT_HEADER_SIZE +
1.148 + aFrame->GetFrameData().Length(),
1.149 + "write more data > EBML_BUFFER_SIZE");
1.150 + block->SetLength(ebml.offset);
1.151 +}
1.152 +
1.153 +void
1.154 +EbmlComposer::SetVideoConfig(uint32_t aWidth, uint32_t aHeight,
1.155 + uint32_t aDisplayWidth, uint32_t aDisplayHeight,
1.156 + float aFrameRate)
1.157 +{
1.158 + MOZ_ASSERT(aWidth > 0, "Width should > 0");
1.159 + MOZ_ASSERT(aHeight > 0, "Height should > 0");
1.160 + MOZ_ASSERT(aDisplayWidth > 0, "DisplayWidth should > 0");
1.161 + MOZ_ASSERT(aDisplayHeight > 0, "DisplayHeight should > 0");
1.162 + MOZ_ASSERT(aFrameRate > 0, "FrameRate should > 0");
1.163 + mWidth = aWidth;
1.164 + mHeight = aHeight;
1.165 + mDisplayWidth = aDisplayWidth;
1.166 + mDisplayHeight = aDisplayHeight;
1.167 + mFrameRate = aFrameRate;
1.168 +}
1.169 +
1.170 +void
1.171 +EbmlComposer::SetAudioConfig(uint32_t aSampleFreq, uint32_t aChannels,
1.172 + uint32_t aBitDepth)
1.173 +{
1.174 + MOZ_ASSERT(aSampleFreq > 0, "SampleFreq should > 0");
1.175 + MOZ_ASSERT(aBitDepth > 0, "BitDepth should > 0");
1.176 + MOZ_ASSERT(aChannels > 0, "Channels should > 0");
1.177 + mSampleFreq = aSampleFreq;
1.178 + mBitDepth = aBitDepth;
1.179 + mChannels = aChannels;
1.180 +}
1.181 +
1.182 +void
1.183 +EbmlComposer::ExtractBuffer(nsTArray<nsTArray<uint8_t> >* aDestBufs,
1.184 + uint32_t aFlag)
1.185 +{
1.186 + if ((aFlag & ContainerWriter::FLUSH_NEEDED) ||
1.187 + (aFlag & ContainerWriter::GET_HEADER))
1.188 + {
1.189 + FinishMetadata();
1.190 + }
1.191 + if (aFlag & ContainerWriter::FLUSH_NEEDED)
1.192 + {
1.193 + FinishCluster();
1.194 + }
1.195 + // aDestBufs may have some element
1.196 + for (uint32_t i = 0; i < mClusterCanFlushBuffs.Length(); i++) {
1.197 + aDestBufs->AppendElement()->SwapElements(mClusterCanFlushBuffs[i]);
1.198 + }
1.199 + mClusterCanFlushBuffs.Clear();
1.200 +}
1.201 +
1.202 +EbmlComposer::EbmlComposer()
1.203 + : mFlushState(FLUSH_NONE)
1.204 + , mClusterHeaderIndex(0)
1.205 + , mClusterLengthLoc(0)
1.206 + , mClusterTimecode(0)
1.207 + , mWidth(0)
1.208 + , mHeight(0)
1.209 + , mFrameRate(0)
1.210 + , mSampleFreq(0)
1.211 + , mBitDepth(0)
1.212 + , mChannels(0)
1.213 +{}
1.214 +
1.215 +}
