The Tor Browser: content/media/encoder/VorbisTrackEncoder.cpp@44a2da4a2ab2 (annotated)

content/media/encoder/VorbisTrackEncoder.cpp@44a2da4a2ab2 (annotated)

content/media/encoder/VorbisTrackEncoder.cpp

Fri, 16 Jan 2015 04:50:19 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Fri, 16 Jan 2015 04:50:19 +0100
branch: TOR_BUG_9701
changeset 13: 44a2da4a2ab2
permissions: -rw-r--r--

Replace accessor implementation with direct member state manipulation, by
request https://trac.torproject.org/projects/tor/ticket/9701#comment:32

 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-*/
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
  * You can obtain one at http://mozilla.org/MPL/2.0/. */
 #include "VorbisTrackEncoder.h"
 #include <ogg/ogg.h>
 #include <vorbis/vorbisenc.h>
 #include "WebMWriter.h"
 // One actually used: Encoding using a VBR quality mode. The usable range is -.1
 // (lowest quality, smallest file) to 1. (highest quality, largest file).
 // Example quality mode .4: 44kHz stereo coupled, roughly 128kbps VBR
 // ret = vorbis_encode_init_vbr(&vi,2,44100,.4);
 static const float BASE_QUALITY = 0.4f;
 namespace mozilla {
 #undef LOG
 #ifdef PR_LOGGING
 PRLogModuleInfo* gVorbisTrackEncoderLog;
 #define VORBISLOG(msg, ...) PR_LOG(gVorbisTrackEncoderLog, PR_LOG_DEBUG, \
                              (msg, ##__VA_ARGS__))
 #else
 #define VORBISLOG(msg, ...)
 #endif
 VorbisTrackEncoder::VorbisTrackEncoder()
   : AudioTrackEncoder()
 {
   MOZ_COUNT_CTOR(VorbisTrackEncoder);
 #ifdef PR_LOGGING
   if (!gVorbisTrackEncoderLog) {
     gVorbisTrackEncoderLog = PR_NewLogModule("VorbisTrackEncoder");
   }
 #endif
 }
 VorbisTrackEncoder::~VorbisTrackEncoder()
 {
   MOZ_COUNT_DTOR(VorbisTrackEncoder);
   if (mInitialized) {
     vorbis_block_clear(&mVorbisBlock);
     vorbis_dsp_clear(&mVorbisDsp);
     vorbis_info_clear(&mVorbisInfo);
   }
 }
 nsresult
 VorbisTrackEncoder::Init(int aChannels, int aSamplingRate)
 {
   if (aChannels <= 0 || aChannels > 8) {
     VORBISLOG("aChannels <= 0 || aChannels > 8");
     return NS_ERROR_INVALID_ARG;
   }
   // This monitor is used to wake up other methods that are waiting for encoder
   // to be completely initialized.
   ReentrantMonitorAutoEnter mon(mReentrantMonitor);
   mChannels = aChannels;
   mSamplingRate = aSamplingRate;
   int ret = 0;
   vorbis_info_init(&mVorbisInfo);
   ret = vorbis_encode_init_vbr(&mVorbisInfo, mChannels, mSamplingRate,
                                BASE_QUALITY);
   mInitialized = (ret == 0);
   if (mInitialized) {
     // Set up the analysis state and auxiliary encoding storage
     vorbis_analysis_init(&mVorbisDsp, &mVorbisInfo);
     vorbis_block_init(&mVorbisDsp, &mVorbisBlock);
   }
   mon.NotifyAll();
   return ret == 0 ? NS_OK : NS_ERROR_FAILURE;
 }
 void VorbisTrackEncoder::WriteLacing(nsTArray<uint8_t> *aOutput, int32_t aLacing)
 {
   while (aLacing >= 255) {
     aLacing -= 255;
     aOutput->AppendElement(255);
   }
   aOutput->AppendElement((uint8_t)aLacing);
 }
 already_AddRefed<TrackMetadataBase>
 VorbisTrackEncoder::GetMetadata()
 {
   {
     // Wait if encoder is not initialized.
     ReentrantMonitorAutoEnter mon(mReentrantMonitor);
     while (!mCanceled && !mInitialized) {
       mon.Wait();
     }
   }
   if (mCanceled || mEncodingComplete) {
     return nullptr;
   }
   // Vorbis codec specific data
   // http://matroska.org/technical/specs/codecid/index.html
   nsRefPtr<VorbisMetadata> meta = new VorbisMetadata();
   meta->mBitDepth = 32; // float for desktop
   meta->mChannels = mChannels;
   meta->mSamplingFrequency = mSamplingRate;
   ogg_packet header;
   ogg_packet header_comm;
   ogg_packet header_code;
   // Add comment
   vorbis_comment vorbisComment;
   vorbis_comment_init(&vorbisComment);
   vorbis_comment_add_tag(&vorbisComment, "ENCODER",
     NS_LITERAL_CSTRING("Mozilla VorbisTrackEncoder " MOZ_APP_UA_VERSION).get());
   vorbis_analysis_headerout(&mVorbisDsp, &vorbisComment,
                             &header,&header_comm, &header_code);
   vorbis_comment_clear(&vorbisComment);
   // number of distinct packets - 1
   meta->mData.AppendElement(2);
   // Xiph-style lacing header.bytes, header_comm.bytes
   WriteLacing(&(meta->mData), header.bytes);
   WriteLacing(&(meta->mData), header_comm.bytes);
   // Append the three packets
   meta->mData.AppendElements(header.packet, header.bytes);
   meta->mData.AppendElements(header_comm.packet, header_comm.bytes);
   meta->mData.AppendElements(header_code.packet, header_code.bytes);
   return meta.forget();
 }
 void
 VorbisTrackEncoder::GetEncodedFrames(EncodedFrameContainer& aData)
 {
   // vorbis does some data preanalysis, then divvies up blocks for
   // more involved (potentially parallel) processing. Get a single
   // block for encoding now.
   while (vorbis_analysis_blockout(&mVorbisDsp, &mVorbisBlock) == 1) {
     ogg_packet oggPacket;
     if (vorbis_analysis(&mVorbisBlock, &oggPacket) == 0) {
       VORBISLOG("vorbis_analysis_blockout block size %d", oggPacket.bytes);
       EncodedFrame* audiodata = new EncodedFrame();
       audiodata->SetFrameType(EncodedFrame::VORBIS_AUDIO_FRAME);
       nsTArray<uint8_t> frameData;
       frameData.AppendElements(oggPacket.packet, oggPacket.bytes);
       audiodata->SwapInFrameData(frameData);
       aData.AppendEncodedFrame(audiodata);
     }
   }
 }
 nsresult
 VorbisTrackEncoder::GetEncodedTrack(EncodedFrameContainer& aData)
 {
   if (mEosSetInEncoder) {
     return NS_OK;
   }
   nsAutoPtr<AudioSegment> sourceSegment;
   sourceSegment = new AudioSegment();
   {
     // Move all the samples from mRawSegment to sourceSegment. We only hold
     // the monitor in this block.
     ReentrantMonitorAutoEnter mon(mReentrantMonitor);
     // Wait if mEncoder is not initialized, or when not enough raw data, but is
     // not the end of stream nor is being canceled.
     while (!mCanceled && mRawSegment.GetDuration() < GetPacketDuration() &&
            !mEndOfStream) {
       mon.Wait();
     }
     VORBISLOG("GetEncodedTrack passes wait, duration is %lld\n",
       mRawSegment.GetDuration());
     if (mCanceled || mEncodingComplete) {
       return NS_ERROR_FAILURE;
     }
     sourceSegment->AppendFrom(&mRawSegment);
   }
   if (mEndOfStream && (sourceSegment->GetDuration() == 0)
       && !mEosSetInEncoder) {
     mEncodingComplete = true;
     mEosSetInEncoder = true;
     VORBISLOG("[Vorbis] Done encoding.");
     vorbis_analysis_wrote(&mVorbisDsp, 0);
     GetEncodedFrames(aData);
     return NS_OK;
   }
   // Start encoding data.
   AudioSegment::ChunkIterator iter(*sourceSegment);
   AudioDataValue **vorbisBuffer =
     vorbis_analysis_buffer(&mVorbisDsp, (int)sourceSegment->GetDuration());
   int framesCopied = 0;
   nsAutoTArray<AudioDataValue, 9600> interleavedPcm;
   nsAutoTArray<AudioDataValue, 9600> nonInterleavedPcm;
   interleavedPcm.SetLength(sourceSegment->GetDuration() * mChannels);
   nonInterleavedPcm.SetLength(sourceSegment->GetDuration() * mChannels);
   while (!iter.IsEnded()) {
     AudioChunk chunk = *iter;
     int frameToCopy = chunk.GetDuration();
     if (!chunk.IsNull()) {
       InterleaveTrackData(chunk, frameToCopy, mChannels,
                           interleavedPcm.Elements() + framesCopied * mChannels);
     } else { // empty data
       memset(interleavedPcm.Elements() + framesCopied * mChannels, 0,
              frameToCopy * mChannels * sizeof(AudioDataValue));
     }
     framesCopied += frameToCopy;
     iter.Next();
   }
   // De-interleave the interleavedPcm.
   DeInterleaveTrackData(interleavedPcm.Elements(), framesCopied, mChannels,
                         nonInterleavedPcm.Elements());
   // Copy the nonInterleavedPcm to vorbis buffer.
   for(uint8_t i = 0; i < mChannels; ++i) {
     memcpy(vorbisBuffer[i], nonInterleavedPcm.Elements() + framesCopied * i,
            framesCopied * sizeof(AudioDataValue));
   }
   // Now the vorbisBuffer contain the all data in non-interleaved.
   // Tell the library how much we actually submitted.
   vorbis_analysis_wrote(&mVorbisDsp, framesCopied);
   VORBISLOG("vorbis_analysis_wrote framesCopied %d\n", framesCopied);
   GetEncodedFrames(aData);
   return NS_OK;
 }
 } // namespace mozilla

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content/media/encoder/VorbisTrackEncoder.cpp@44a2da4a2ab2 (annotated)

content/media/encoder/VorbisTrackEncoder.cpp