Added MPEG-H support (mha1, mhm1)

Implemented according to `Audio Amendment to Guidelines for Implementation:
DASH-IF Interoperability Points, Version 4.3`
(https://dashif.org/docs/Audio%20Amendment%20to%20DASH%20IOP%204.3.pdf).

Closes #930.

AUTHORS

@@ -15,6 +15,7 @@
 
 3Q GmbH <*@3qsdn.com>
 Alen Vrecko <alen.vrecko@gmail.com>
+Amazon Music <*@amazon.com>
 Anders Hasselqvist <anders.hasselqvist@gmail.com>
 Audible <*@audible.com>
 Chun-da Chen <capitalm.c@gmail.com>

CONTRIBUTORS

@@ -48,4 +48,5 @@ Sanil Raut <sr1990003@gmail.com>
 Sergio Ammirata <sergio@ammirata.net>
 Thomas Inskip <tinskip@google.com>
 Tim Lansen <tim.lansen@gmail.com>
+Vincent Nguyen <nvincen@amazon.com>
 Weiguo Shao <weiguo.shao@dolby.com>

README.md

@@ -43,6 +43,7 @@ Shaka Packager supports:
   |       MP3         |      O       |      -       |     I / O    |      -      |       O      |
   |    Dolby AC3      |    I / O     |      -       |     I / O    |      -      |       O      |
   |    Dolby EAC3     |    I / O     |      -       |       O      |      -      |       O      |
+  |   MPEG-H Audio    |    I / O     |      -       |       -      |      -      |       -      |
   |    Dolby AC4      |    I / O     |      -       |       -      |      -      |       -      |
   |       DTS         |    I / O     |      -       |       -      |      -      |       -      |
   |       FLAC        |    I / O     |      -       |       -      |      -      |       -      |

packager/media/base/audio_stream_info.cc

@@ -52,6 +52,17 @@ std::string AudioCodecToString(Codec codec) {
       return "UnknownCodec";
   }
 }
+
+FourCC CodecToFourCC(Codec codec) {
+  switch (codec) {
+    case kCodecMha1:
+      return FOURCC_mha1;
+    case kCodecMhm1:
+      return FOURCC_mhm1;
+    default:
+      return FOURCC_NULL;
+  }
+}
 }  // namespace
 
 AudioStreamInfo::AudioStreamInfo(
@@ -139,6 +150,17 @@ std::string AudioStreamInfo::GetCodecString(Codec codec,
       return "mp3";
     case kCodecVorbis:
       return "vorbis";
+    case kCodecMha1:
+    case kCodecMhm1:
+      // The signalling of the codecs parameters is according to RFC6381 [11]
+      //   and ISO/IEC 23008-3 clause 21 [7].
+      // The value consists of the following two parts separated by a dot:
+      //  - the sample entry 4CC code ('mha1', 'mha2', 'mhm1', 'mhm2')
+      //  - ‘0x’ followed by the hex value of the profile-levelid, as defined 
+      //      in in ISO/IEC 23008-3 [7]
+      return base::StringPrintf("%s.0x%02x", 
+                                FourCCToString(CodecToFourCC(codec)).c_str(), 
+                                audio_object_type);
     default:
       NOTIMPLEMENTED() << "Codec: " << codec;
       return "unknown";

packager/media/base/fourccs.h

@@ -89,6 +89,9 @@ enum FourCC : uint32_t {
   FOURCC_meta = 0x6d657461,
   FOURCC_mfhd = 0x6d666864,
   FOURCC_mfra = 0x6d667261,
+  FOURCC_mha1 = 0x6d686131,
+  FOURCC_mhaC = 0x6d686143,
+  FOURCC_mhm1 = 0x6d686d31,
   FOURCC_minf = 0x6d696e66,
   FOURCC_moof = 0x6d6f6f66,
   FOURCC_moov = 0x6d6f6f76,

packager/media/base/stream_info.h

@@ -54,6 +54,8 @@ enum Codec {
   kCodecOpus,
   kCodecVorbis,
   kCodecMP3,
+  kCodecMha1,
+  kCodecMhm1,
   kCodecAudioMaxPlusOne,
 
   kCodecText = 300,

packager/media/formats/mp4/box_definitions.cc

@@ -1709,6 +1709,29 @@ size_t ElementaryStreamDescriptor::ComputeSizeInternal() {
   return HeaderSize() + es_descriptor.ComputeSize();
 }
 
+MHAConfiguration::MHAConfiguration() = default;
+MHAConfiguration::~MHAConfiguration() = default;
+
+FourCC MHAConfiguration::BoxType() const {
+  return FOURCC_mhaC;
+}
+
+bool MHAConfiguration::ReadWriteInternal(BoxBuffer* buffer) {
+  RCHECK(ReadWriteHeaderInternal(buffer) &&
+         buffer->ReadWriteVector(
+             &data, buffer->Reading() ? buffer->BytesLeft() : data.size()));
+  RCHECK(data.size() > 1);
+  mpeg_h_3da_profile_level_indication = data[1];
+  return true;
+}
+
+size_t MHAConfiguration::ComputeSizeInternal() {
+  // This box is optional. Skip it if not initialized.
+  if (data.empty())
+    return 0;
+  return HeaderSize() + data.size();
+}
+
 DTSSpecific::DTSSpecific() = default;
 DTSSpecific::~DTSSpecific() = default;
 ;
@@ -1922,6 +1945,7 @@ bool AudioSampleEntry::ReadWriteInternal(BoxBuffer* buffer) {
   RCHECK(buffer->TryReadWriteChild(&dac4));
   RCHECK(buffer->TryReadWriteChild(&dops));
   RCHECK(buffer->TryReadWriteChild(&dfla));
+  RCHECK(buffer->TryReadWriteChild(&mhac));
 
   // Somehow Edge does not support having sinf box before codec_configuration,
   // box, so just do it in the end of AudioSampleEntry. See
@@ -1947,7 +1971,7 @@ size_t AudioSampleEntry::ComputeSizeInternal() {
          sizeof(samplesize) + sizeof(samplerate) + sinf.ComputeSize() +
          esds.ComputeSize() + ddts.ComputeSize() + dac3.ComputeSize() +
          dec3.ComputeSize() + dops.ComputeSize() + dfla.ComputeSize() +
-         dac4.ComputeSize() +
+         dac4.ComputeSize() + mhac.ComputeSize() +
          // Reserved and predefined bytes.
          6 + 8 +  // 6 + 8 bytes reserved.
          4;       // 4 bytes predefined.

packager/media/formats/mp4/box_definitions.h

@@ -328,6 +328,13 @@ struct AC3Specific : Box {
   std::vector<uint8_t> data;
 };
 
+struct MHAConfiguration : Box {
+  DECLARE_BOX_METHODS(MHAConfiguration);
+
+  std::vector<uint8_t> data;
+  uint8_t mpeg_h_3da_profile_level_indication;
+};
+
 struct EC3Specific : Box {
   DECLARE_BOX_METHODS(EC3Specific);
 
@@ -382,6 +389,7 @@ struct AudioSampleEntry : Box {
   AC4Specific dac4;
   OpusSpecific dops;
   FlacSpecific dfla;
+  MHAConfiguration mhac;
 };
 
 struct WebVTTConfigurationBox : Box {

packager/media/formats/mp4/box_definitions_unittest.cc

@@ -1222,6 +1222,21 @@ TEST_F(BoxDefinitionsTest, AC3SampleEntry) {
   ASSERT_EQ(entry, entry_readback);
 }
 
+TEST_F(BoxDefinitionsTest, MHA1SampleEntry) {
+  AudioSampleEntry entry;
+  entry.format = FOURCC_mha1;
+  entry.data_reference_index = 2;
+  entry.channelcount = 5;
+  entry.samplesize = 16;
+  entry.samplerate = 44100;
+  Fill(&entry.mhac);
+  entry.Write(this->buffer_.get());
+
+  AudioSampleEntry entry_readback;
+  ASSERT_TRUE(ReadBack(&entry_readback));
+  ASSERT_EQ(entry, entry_readback);
+}
+
 TEST_F(BoxDefinitionsTest, EC3SampleEntry) {
   AudioSampleEntry entry;
   entry.format = FOURCC_ec_3;

packager/media/formats/mp4/mp4_media_parser.cc

@@ -99,6 +99,10 @@ Codec FourCCToCodec(FourCC fourcc) {
       return kCodecAC4;
     case FOURCC_fLaC:
       return kCodecFlac;
+    case FOURCC_mha1:
+      return kCodecMha1;
+    case FOURCC_mhm1:
+      return kCodecMhm1;
     default:
       return kUnknownCodec;
   }
@@ -510,6 +514,11 @@ bool MP4MediaParser::ParseMoov(BoxReader* reader) {
           codec_delay_ns =
               entry.dops.preskip * kNanosecondsPerSecond / sampling_frequency;
           break;
+        case FOURCC_mha1:
+        case FOURCC_mhm1:
+          codec_config = entry.mhac.data;
+          audio_object_type = entry.mhac.mpeg_h_3da_profile_level_indication;
+          break;
         default:
           // Intentionally not to fail in the parser as there may be multiple
           // streams in the source content, which allows the supported stream to

packager/media/formats/mp4/mp4_muxer.cc

@@ -90,6 +90,10 @@ FourCC CodecToFourCC(Codec codec, H26xStreamFormat h26x_stream_format) {
       return FOURCC_fLaC;
     case kCodecOpus:
       return FOURCC_Opus;
+    case kCodecMha1:
+      return FOURCC_mha1;
+    case kCodecMhm1:
+      return FOURCC_mhm1;
     default:
       return FOURCC_NULL;
   }
@@ -513,6 +517,10 @@ bool MP4Muxer::GenerateAudioTrak(const AudioStreamInfo* audio_info,
     case kCodecOpus:
       audio.dops.opus_identification_header = audio_info->codec_config();
       break;
+    case kCodecMha1:
+    case kCodecMhm1:
+      audio.mhac.data = audio_info->codec_config();
+      break;
     default:
       NOTIMPLEMENTED() << " Unsupported audio codec " << audio_info->codec();
       return false;