Re-add AC3/EAC3 audio demuxing support

net/base/mime_util.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <algorithm>
 #include <iterator>
 #include <map>
 #include <string>
 
 #include "base/containers/hash_tables.h"
@@ skipping 30 matching lines @@
     MPEG4_AAC_SBR_v1,
     MPEG4_AAC_SBR_PS_v2,
     VORBIS,
     OPUS,
     H264_BASELINE,
     H264_MAIN,
     H264_HIGH,
     VP8,
     VP9,
     THEORA
+#if defined(ENABLE_AC3_EAC3_AUDIO_DEMUXING)
+    ,
+    AC3,
+    EAC3
+#endif
   };
 
   bool GetMimeTypeFromExtension(const base::FilePath::StringType& ext,
                                 std::string* mime_type) const;
 
   bool GetMimeTypeFromFile(const base::FilePath& file_path,
                            std::string* mime_type) const;
 
   bool GetWellKnownMimeTypeFromExtension(const base::FilePath::StringType& ext,
                                          std::string* mime_type) const;
@@ skipping 404 matching lines @@
     case MimeUtil::VP8:
     case MimeUtil::VORBIS:
       return true;
 
     case MimeUtil::MPEG2_AAC_LC:
     case MimeUtil::MPEG2_AAC_MAIN:
     case MimeUtil::MPEG2_AAC_SSR:
       // MPEG-2 variants of AAC are not supported on Android.
       return false;
 
+#if defined(ENABLE_AC3_EAC3_AUDIO_DEMUXING)
+    case MimeUtil::AC3:
+    case MimeUtil::EAC3:
+      // TODO(servolk): Revisit this for AC3/EAC3 support on AndroidTV
+      return false;
+#endif
+
     case MimeUtil::VP9:
       // VP9 is supported only in KitKat+ (API Level 19).
       return base::android::BuildInfo::GetInstance()->sdk_int() >= 19;
 
     case MimeUtil::OPUS:
       // Opus is supported only in Lollipop+ (API Level 21).
       return base::android::BuildInfo::GetInstance()->sdk_int() >= 21;
 
     case MimeUtil::THEORA:
       return false;
@@ skipping 29 matching lines @@
 //   mp4a.40.5   - MPEG-4 HE-AAC v1 (AAC LC + SBR)
 //   mp4a.40.05  - MPEG-4 HE-AAC v1 (AAC LC + SBR) (leading 0 in aud-oti for
 //                 compatibility)
 //   mp4a.40.29  - MPEG-4 HE-AAC v2 (AAC LC + SBR + PS)
 //
 //   avc1.42E0xx - H.264 Baseline
 //   avc1.4D40xx - H.264 Main
 //   avc1.6400xx - H.264 High
 static const char kMP4AudioCodecsExpression[] =
     "mp4a.66,mp4a.67,mp4a.68,mp4a.69,mp4a.6B,mp4a.40.2,mp4a.40.02,mp4a.40.5,"
+#if defined(ENABLE_AC3_EAC3_AUDIO_DEMUXING)
+    "ac-3,ec-3,"  // Note: only one variant of eac codec string is sufficient
+                  // here since these are converted into enums in
+                  // InitializeMimeTypeMaps
+#endif
     "mp4a.40.05,mp4a.40.29";
 static const char kMP4VideoCodecsExpression[] =
     // This is not a complete list of supported avc1 codecs. It is simply used
     // to register support for the corresponding Codec enum. Instead of using
     // strings in these three arrays, we should use the Codec enum values.
     // This will avoid confusion and unnecessary parsing at runtime.
     // kUnambiguousCodecStringMap/kAmbiguousCodecStringMap should be the only
     // mapping from strings to codecs. See crbug.com/461009.
     "avc1.42E00A,avc1.4D400A,avc1.64000A,"
+#if defined(ENABLE_AC3_EAC3_AUDIO_DEMUXING)
+    "ac-3,ec-3,"  // Note: only one variant of eac codec string is sufficient
+                  // here since these are converted into enums in
+                  // InitializeMimeTypeMaps
+#endif
     "mp4a.66,mp4a.67,mp4a.68,mp4a.69,mp4a.6B,mp4a.40.2,mp4a.40.02,mp4a.40.5,"
     "mp4a.40.05,mp4a.40.29";
 
 // These containers are also included in
 // common_media_types/proprietary_media_types. See crbug.com/461012.
 static const MediaFormatStrict format_codec_mappings[] = {
     {"video/webm", "opus,vorbis,vp8,vp8.0,vp9,vp9.0"},
     {"audio/webm", "opus,vorbis"},
     {"audio/wav", "1"},
     {"audio/x-wav", "1"},
@@ skipping 33 matching lines @@
     {"mp4a.66", MimeUtil::MPEG2_AAC_MAIN},
     {"mp4a.67", MimeUtil::MPEG2_AAC_LC},
     {"mp4a.68", MimeUtil::MPEG2_AAC_SSR},
     {"mp4a.69", MimeUtil::MP3},
     {"mp4a.6B", MimeUtil::MP3},
     {"mp4a.40.2", MimeUtil::MPEG4_AAC_LC},
     {"mp4a.40.02", MimeUtil::MPEG4_AAC_LC},
     {"mp4a.40.5", MimeUtil::MPEG4_AAC_SBR_v1},
     {"mp4a.40.05", MimeUtil::MPEG4_AAC_SBR_v1},
     {"mp4a.40.29", MimeUtil::MPEG4_AAC_SBR_PS_v2},
+#if defined(ENABLE_AC3_EAC3_AUDIO_DEMUXING)
+    {"ac-3", MimeUtil::AC3},
+    {"ec-3", MimeUtil::EAC3},
+    {"mp4a.a5", MimeUtil::AC3},
+    {"mp4a.a6", MimeUtil::EAC3},
+#endif
     {"vorbis", MimeUtil::VORBIS},
     {"opus", MimeUtil::OPUS},
     {"vp8", MimeUtil::VP8},
     {"vp8.0", MimeUtil::VP8},
     {"vp9", MimeUtil::VP9},
     {"vp9.0", MimeUtil::VP9},
     {"theora", MimeUtil::THEORA}};
 
 // List of codec IDs that are ambiguous and don't provide
 // enough information to determine the codec and profile.
@@ skipping 305 matching lines @@
   base::TrimString(codecs, "\"", &no_quote_codecs);
   base::SplitString(no_quote_codecs, ',', codecs_out);
 
   if (!strip)
     return;
 
   // Strip everything past the first '.'
   for (std::vector<std::string>::iterator it = codecs_out->begin();
        it != codecs_out->end();
        ++it) {
+#if defined(ENABLE_AC3_EAC3_AUDIO_DEMUXING)
+    // We need to know the codec subtype to properly support AC3/EAC3.
+    // Do not strip the first '.' for mp4a.a5 and mp4a.a6.
+    if (it->compare("mp4a.a5") == 0 || it->compare("mp4a.a6") == 0) {
+      continue;
+    }
+#endif
     size_t found = it->find_first_of('.');
     if (found != std::string::npos)
       it->resize(found);
   }
 }
 
 bool MimeUtil::IsStrictMediaMimeType(const std::string& mime_type) const {
   return strict_format_map_.find(base::StringToLowerASCII(mime_type)) !=
          strict_format_map_.end();
 }
@@ skipping 156 matching lines @@
     case MP3:
     case MPEG2_AAC_LC:
     case MPEG2_AAC_MAIN:
     case MPEG2_AAC_SSR:
     case MPEG4_AAC_LC:
     case MPEG4_AAC_SBR_v1:
     case MPEG4_AAC_SBR_PS_v2:
     case H264_BASELINE:
     case H264_MAIN:
     case H264_HIGH:
+#if defined(ENABLE_AC3_EAC3_AUDIO_DEMUXING)
+    case AC3:
+    case EAC3:
+#endif
       return true;
 
     case PCM:
     case VORBIS:
     case OPUS:
     case VP8:
     case VP9:
     case THEORA:
       return false;
   }
@@ skipping 330 matching lines @@
   post_data->append("\r\n" + value + "\r\n");
 }
 
 void AddMultipartFinalDelimiterForUpload(const std::string& mime_boundary,
                                          std::string* post_data) {
   DCHECK(post_data);
   post_data->append("--" + mime_boundary + "--\r\n");
 }
 
 }  // namespace net