Implement IAMF v1.0.0 errata changes

Updates the IAMF mp4 parsing implementation to support v1.0.0-errata.
Streams configured with the original v1.0.0 spec are no longer
supported.

Changes are pulled from Chromium. Original CL descriptions follow:

Update IAMF mp4 parsing implementation

Updates the IAMF parsing implemenation to parse the IA Configuration Box
defined in the IAMF v1.0.0-errata specification.

https://aomediacodec.github.io/iamf/v1.0.0-errata.html#iaconfigurationbox-section

Bug: b/340618404
Change-Id: I1467e60928ac28e0ead4a9e0f3857b6c5540c7e7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5550540
Reviewed-by: Mark Foltz <[email protected]>
Commit-Queue: Austin Osagie <[email protected]>
Reviewed-by: Dale Curtis <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1304144}

Fix iacb atom parsing error

Fixes an error in a previous change that parses the iamf atom instead of
the iacb atom. Now, the iacb atom is properly read.

Bug: b/340618404
Change-Id: I61d8c8c2758c9181b40ff6e99da24c790b202687

third_party/chromium/media/formats/mp4/box_definitions.cc

@@ -1456,15 +1456,21 @@ IamfSpecificBox::IamfSpecificBox(const IamfSpecificBox& other) = default;
 IamfSpecificBox::~IamfSpecificBox() = default;
 
 FourCC IamfSpecificBox::BoxType() const {
-  return FOURCC_IAMF;
+  return FOURCC_IACB;
 }
 
 bool IamfSpecificBox::Parse(BoxReader* reader) {
-  const int obu_bitstream_size = reader->box_size() - reader->pos();
+  uint8_t configuration_version;
+  RCHECK(reader->Read1(&configuration_version));
+  RCHECK(configuration_version == 0x01);
+
+  uint32_t config_obus_size;
+  RCHECK(ReadLeb128Value(reader, &config_obus_size));
+
   const uint8_t* buf = reader->buffer() + reader->pos();
-  ia_descriptors.assign(buf, buf + obu_bitstream_size);
+  ia_descriptors.assign(buf, buf + config_obus_size);
 
-  RCHECK(reader->SkipBytes(obu_bitstream_size));
+  RCHECK(reader->SkipBytes(config_obus_size));
 
   BufferReader config_reader(ia_descriptors.data(), ia_descriptors.size());
 
@@ -1582,14 +1588,6 @@ bool AudioSampleEntry::Parse(BoxReader* reader) {
   // Convert from 16.16 fixed point to integer
   samplerate >>= 16;
 
-#if BUILDFLAG(ENABLE_PLATFORM_IAMF_AUDIO)
-  if (format == FOURCC_IAMF) {
-    RCHECK_MEDIA_LOGGED(iamf.Parse(reader), reader->media_log(),
-                        "Failure parsing IamfSpecificBox (iamf)");
-    return true;
-  }
-#endif  // BUILDFLAG(ENABLE_PLATFORM_IAMF_AUDIO)
-
   RCHECK(reader->ScanChildren());
   if (format == FOURCC_ENCA) {
     // Continue scanning until a recognized protection scheme is found, or until
@@ -1612,6 +1610,14 @@ bool AudioSampleEntry::Parse(BoxReader* reader) {
                         "OpusSpecificBox STREAMINFO channel count");
   }
 
+#if BUILDFLAG(ENABLE_PLATFORM_IAMF_AUDIO)
+  if (format == FOURCC_IAMF) {
+    RCHECK_MEDIA_LOGGED(reader->ReadChild(&iacb), reader->media_log(),
+                        "Failure parsing IamfSpecificBox (iacb)");
+    return true;
+  }
+#endif  // BUILDFLAG(ENABLE_PLATFORM_IAMF_AUDIO)
+
   // Read the FLACSpecificBox, even if CENC is signalled.
   if (format == FOURCC_FLAC ||
       (format == FOURCC_ENCA && sinf.format.format == FOURCC_FLAC)) {

third_party/chromium/media/formats/mp4/box_definitions.h

@@ -408,7 +408,7 @@ struct MEDIA_EXPORT AudioSampleEntry : Box {
   FlacSpecificBox dfla;
   OpusSpecificBox dops;
 #if BUILDFLAG(ENABLE_PLATFORM_IAMF_AUDIO)
-  IamfSpecificBox iamf;
+  IamfSpecificBox iacb;
 #endif  // BUILDFLAG(ENABLE_PLATFORM_IAMF_AUDIO)
 };
 

third_party/chromium/media/formats/mp4/fourccs.h

@@ -64,6 +64,7 @@ enum FourCC {
   FOURCC_HVCC = 0x68766343,
 #endif
 #if BUILDFLAG(ENABLE_PLATFORM_IAMF_AUDIO)
+  FOURCC_IACB = 0x69616362,
   FOURCC_IAMF = 0x69616d66,
 #endif  // BUILDFLAG(ENABLE_PLATFORM_IAMF_AUDIO)
   FOURCC_ID32 = 0x49443332,

third_party/chromium/media/formats/mp4/mp4_stream_parser.cc

@@ -397,7 +397,7 @@ bool MP4StreamParser::ParseMoov(BoxReader* reader) {
         }
 
         codec = AudioCodec::kIAMF;
-        profile = entry.iamf.profile == 0 ? AudioCodecProfile::kIAMF_SIMPLE
+        profile = entry.iacb.profile == 0 ? AudioCodecProfile::kIAMF_SIMPLE
                                           : AudioCodecProfile::kIAMF_BASE;
         // The correct values for the channel layout and sample rate can
         // be parsed from the descriptor bitstream prepended to each sample.
@@ -755,18 +755,18 @@ bool MP4StreamParser::PrepareAACBuffer(
 
 #if BUILDFLAG(ENABLE_PLATFORM_IAMF_AUDIO)
 bool MP4StreamParser::PrependIADescriptors(
-    const IamfSpecificBox& iamf_box,
+    const IamfSpecificBox& iacb,
     std::vector<uint8_t>* frame_buf,
     std::vector<SubsampleEntry>* subsamples) const {
   // Prepend the IA Descriptors to every IA Sample.
-  frame_buf->insert(frame_buf->begin(), iamf_box.ia_descriptors.begin(),
-                    iamf_box.ia_descriptors.end());
+  frame_buf->insert(frame_buf->begin(), iacb.ia_descriptors.begin(),
+                    iacb.ia_descriptors.end());
+  size_t descriptors_size = iacb.ia_descriptors.size();
   if (subsamples->empty()) {
     subsamples->push_back(
-        SubsampleEntry(iamf_box.ia_descriptors.size(),
-                       frame_buf->size() - iamf_box.ia_descriptors.size()));
+        SubsampleEntry(descriptors_size, frame_buf->size() - descriptors_size));
   } else {
-    (*subsamples)[0].clear_bytes += iamf_box.ia_descriptors.size();
+    (*subsamples)[0].clear_bytes += descriptors_size;
   }
 
   return true;
@@ -939,7 +939,7 @@ ParseResult MP4StreamParser::EnqueueSample(BufferQueueMap* buffers) {
     } else {
 #if BUILDFLAG(ENABLE_PLATFORM_IAMF_AUDIO)
       if (runs_->audio_description().format == FOURCC_IAMF) {
-        if (!PrependIADescriptors(runs_->audio_description().iamf, &frame_buf,
+        if (!PrependIADescriptors(runs_->audio_description().iacb, &frame_buf,
                                   &subsamples)) {
           MEDIA_LOG(ERROR, media_log_)
               << "Failed to prepare IA sample for decode";

third_party/chromium/media/formats/mp4/mp4_stream_parser.h

@@ -95,7 +95,7 @@ class MEDIA_EXPORT MP4StreamParser : public StreamParser {
                         std::vector<SubsampleEntry>* subsamples) const;
 #endif
 #if BUILDFLAG(ENABLE_PLATFORM_IAMF_AUDIO)
-  bool PrependIADescriptors(const IamfSpecificBox& iamf_box,
+  bool PrependIADescriptors(const IamfSpecificBox& iacb,
                             std::vector<uint8_t>* frame_buf,
                             std::vector<SubsampleEntry>* subsamples) const;
 #endif  // BUILDFLAG(ENABLE_PLATFORM_IAMF_AUDIO)