Commit 447d5112 authored by Eugen Sawin's avatar Eugen Sawin Committed by Georg Koppen
Browse files

Bug 1291543 - [1.1] Accept partial information from VBR headers. r=jya 

This fixes our bug 20160.
parent 421cd216

dom/media/MP3Demuxer.cpp

+10 −6
Original line number Diff line number Diff line
@@ -347,7 +347,7 @@ MP3TrackDemuxer::Duration() const { 


  int64_t numFrames = 0;

  const auto numAudioFrames = mParser.VBRInfo().NumAudioFrames();

  if (mParser.VBRInfo().IsValid()) {

  if (mParser.VBRInfo().IsValid() && numAudioFrames.valueOr(0) + 1 > 1) {

    // VBR headers don't include the VBR header frame.

    numFrames = numAudioFrames.value() + 1;

  } else {
@@ -513,7 +513,6 @@ MP3TrackDemuxer::GetNextFrame(const MediaByteRange& aRange) { 


  if (mNumParsedFrames == 1) {

    // First frame parsed, let's read VBR info if available.

    // TODO: read info that helps with seeking (bug 1163667).

    ByteReader reader(frame->Data(), frame->Size());

    mParser.ParseVBRHeader(&reader);

    reader.DiscardRemaining();
@@ -534,7 +533,7 @@ MP3TrackDemuxer::OffsetFromFrameIndex(int64_t aFrameIndex) const { 
  int64_t offset = 0;

  const auto& vbr = mParser.VBRInfo();



  if (vbr.IsValid()) {

  if (vbr.IsComplete()) {

    offset = mFirstFrameOffset + aFrameIndex * vbr.NumBytes().value() /

             vbr.NumAudioFrames().value();

  } else if (AverageFrameLength() > 0) {
@@ -550,7 +549,7 @@ MP3TrackDemuxer::FrameIndexFromOffset(int64_t aOffset) const { 
  int64_t frameIndex = 0;

  const auto& vbr = mParser.VBRInfo();



  if (vbr.IsValid()) {

  if (vbr.IsComplete()) {

    frameIndex = static_cast<float>(aOffset - mFirstFrameOffset) /

                 vbr.NumBytes().value() * vbr.NumAudioFrames().value();

    frameIndex = std::min<int64_t>(vbr.NumAudioFrames().value(), frameIndex);
@@ -626,7 +625,7 @@ MP3TrackDemuxer::AverageFrameLength() const { 
    return static_cast<double>(mTotalFrameLen) / mNumParsedFrames;

  }

  const auto& vbr = mParser.VBRInfo();

  if (vbr.IsValid() && vbr.NumAudioFrames().value() + 1) {

  if (vbr.IsComplete() && vbr.NumAudioFrames().value() + 1) {

    return static_cast<double>(vbr.NumBytes().value()) /

           (vbr.NumAudioFrames().value() + 1);

  }
@@ -964,7 +963,12 @@ FrameParser::VBRHeader::IsTOCPresent() const { 


bool

FrameParser::VBRHeader::IsValid() const {

  return mType != NONE &&

  return mType != NONE;

}



bool

FrameParser::VBRHeader::IsComplete() const {

  return IsValid() &&

         mNumAudioFrames.valueOr(0) > 0 &&

         mNumBytes.valueOr(0) > 0 &&

         // We don't care about the scale for any computations here.

dom/media/MP3Demuxer.h

+4 −1
Original line number Diff line number Diff line
@@ -232,9 +232,12 @@ public: 
    // Returns true iff Xing/Info TOC (table of contents) is present.

    bool IsTOCPresent() const;



    // Returns whether the header is valid (containing reasonable field values).

    // Returns whether the header is valid (type XING or VBRI).

    bool IsValid() const;



    // Returns whether the header is valid and contains reasonable non-zero field values.

    bool IsComplete() const;



    // Returns the byte offset for the given duration percentage as a factor

    // (0: begin, 1.0: end).

    int64_t Offset(float aDurationFac) const;