Support album artist and fix/improve grouping

CMakeLists.txt

@@ -179,8 +179,8 @@ set(META_APP_AUTHOR "Martchus")
 set(META_APP_URL "https://github.com/${META_APP_AUTHOR}/${META_PROJECT_NAME}")
 set(META_APP_DESCRIPTION "C++ library for reading and writing MP4 (iTunes), ID3, Vorbis, Opus, FLAC and Matroska tags")
 set(META_VERSION_MAJOR 8)
-set(META_VERSION_MINOR 0)
+set(META_VERSION_MINOR 1)
-set(META_VERSION_PATCH 2)
+set(META_VERSION_PATCH 0)
 set(META_PUBLIC_SHARED_LIB_DEPENDS c++utilities)
 set(META_PUBLIC_STATIC_LIB_DEPENDS c++utilities_static)
 set(META_REQUIRED_CPP_UNIT_VERSION 1.14.0)

id3/id3v2frameids.cpp

@@ -59,6 +59,8 @@ uint32 convertToShortId(uint32 id)
         return sUnsynchronizedLyrics;
     case lGrouping:
         return sGrouping;
+    case lContentGroupDescription:
+        return sContentGroupDescription;
     case lRecordLabel:
         return sRecordLabel;
     case lUserDefinedText:
@@ -111,6 +113,8 @@ uint32 convertToLongId(uint32 id)
         return lUnsynchronizedLyrics;
     case sGrouping:
         return lGrouping;
+    case sContentGroupDescription:
+        return lContentGroupDescription;
     case sRecordLabel:
         return lRecordLabel;
     case sUserDefinedText:

id3/id3v2frameids.h

@@ -27,7 +27,8 @@ enum KnownValue : uint32 {
     lEncoderSettings = 0x54535345,
     lUnsynchronizedLyrics = 0x55534c54,
     lSynchronizedLyrics = 0x53594C54,
-    lGrouping = 0x54504532,
+    lGrouping = 0x54504532, // FIXME: rename to lAlbumArtist in v9
+    lContentGroupDescription = 0x54495431,
     lRecordLabel = 0x54505542,
     lUniqueFileId = 0x55464944,
     lComposer = 0x54434f4d,
@@ -52,7 +53,8 @@ enum KnownValue : uint32 {
     sEncoderSettings = 0x545353,
     sUnsynchronizedLyrics = 0x554C54,
     sSynchronizedLyrics = 0x534C54,
-    sGrouping = 0x545032,
+    sGrouping = 0x545032, // FIXME: rename to sAlbumArtist in v9
+    sContentGroupDescription = 0x545431,
     sRecordLabel = 0x545042,
     sUniqueFileId = 0x554649,
     sComposer = 0x54434d,

id3/id3v2tag.cpp

@@ -44,6 +44,7 @@ bool Id3v2Tag::supportsMultipleValues(KnownField field) const
     case KnownField::Grouping:
     case KnownField::RecordLabel:
     case KnownField::Composer:
+    case KnownField::AlbumArtist:
         return m_majorVersion > 3;
     case KnownField::Rating:
     case KnownField::Comment:
@@ -166,13 +167,15 @@ Id3v2Tag::IdentifierType Id3v2Tag::internallyGetFieldId(KnownField field) const
         case KnownField::SynchronizedLyrics:
             return lSynchronizedLyrics;
         case KnownField::Grouping:
-            return lGrouping;
+            return lContentGroupDescription;
         case KnownField::RecordLabel:
             return lRecordLabel;
         case KnownField::Composer:
             return lComposer;
         case KnownField::Rating:
             return lRating;
+        case KnownField::AlbumArtist:
+            return lGrouping;
         default:;
         }
     } else {
@@ -214,13 +217,15 @@ Id3v2Tag::IdentifierType Id3v2Tag::internallyGetFieldId(KnownField field) const
         case KnownField::SynchronizedLyrics:
             return sSynchronizedLyrics;
         case KnownField::Grouping:
-            return sGrouping;
+            return sContentGroupDescription;
         case KnownField::RecordLabel:
             return sRecordLabel;
         case KnownField::Composer:
             return sComposer;
         case KnownField::Rating:
             return sRating;
+        case KnownField::AlbumArtist:
+            return sGrouping;
         default:;
         }
     }
@@ -268,6 +273,8 @@ KnownField Id3v2Tag::internallyGetKnownField(const IdentifierType &id) const
     case lSynchronizedLyrics:
         return KnownField::SynchronizedLyrics;
     case lGrouping:
+        return KnownField::AlbumArtist;
+    case lContentGroupDescription:
         return KnownField::Grouping;
     case lRecordLabel:
         return KnownField::RecordLabel;

mp4/mp4tag.cpp

@@ -159,6 +159,8 @@ Mp4Tag::IdentifierType Mp4Tag::internallyGetFieldId(KnownField field) const
         return Performers;
     case KnownField::Lyricist:
         return Lyricist;
+    case KnownField::AlbumArtist:
+        return AlbumArtist;
     default:
         return 0;
     }
@@ -207,6 +209,8 @@ KnownField Mp4Tag::internallyGetKnownField(const IdentifierType &id) const
         return KnownField::Performers;
     case Lyricist:
         return KnownField::Lyricist;
+    case AlbumArtist:
+        return KnownField::AlbumArtist;
     default:
         return KnownField::Invalid;
     }

tag.h

@@ -35,6 +35,8 @@ enum class TagType : unsigned int {
  *
  * Not all fields are supported by all tag types (see Tag::supportsField()).
  *
+ * Mapping proposed by HAK: https://wiki.hydrogenaud.io/index.php?title=Tag_Mapping
+ *
  * \sa Tag::type()
  */
 enum class KnownField : unsigned int {
@@ -66,7 +68,8 @@ enum class KnownField : unsigned int {
     Composer, /**< composer */
     Rating, /**< rating */
     Description, /**< description */
-    Vendor /**< vendor */
+    Vendor, /**< vendor */
+    AlbumArtist, /**< album artist */
 };
 
 /*!

vorbis/vorbiscomment.cpp

@@ -77,6 +77,8 @@ VorbisComment::IdentifierType VorbisComment::internallyGetFieldId(KnownField fie
         return encoderSettings();
     case KnownField::Description:
         return description();
+    case KnownField::Grouping:
+        return grouping();
     case KnownField::RecordLabel:
         return label();
     case KnownField::Performers:
@@ -85,6 +87,8 @@ VorbisComment::IdentifierType VorbisComment::internallyGetFieldId(KnownField fie
         return language();
     case KnownField::Lyricist:
         return lyricist();
+    case KnownField::AlbumArtist:
+        return albumArtist();
     default:
         return string();
     }
@@ -93,12 +97,29 @@ VorbisComment::IdentifierType VorbisComment::internallyGetFieldId(KnownField fie
 KnownField VorbisComment::internallyGetKnownField(const IdentifierType &id) const
 {
     using namespace VorbisCommentIds;
-    static const map<string, KnownField, CaseInsensitiveStringComparer> fieldMap({ { album(), KnownField::Album }, { artist(), KnownField::Artist },
+    // clang-format off
-        { comment(), KnownField::Comment }, { cover(), KnownField::Cover }, { date(), KnownField::Year }, { title(), KnownField::Title },
+    static const map<string, KnownField, CaseInsensitiveStringComparer> fieldMap({
-        { genre(), KnownField::Genre }, { trackNumber(), KnownField::TrackPosition }, { diskNumber(), KnownField::DiskPosition },
+         { album(), KnownField::Album },
-        { partNumber(), KnownField::PartNumber }, { composer(), KnownField::Composer }, { encoder(), KnownField::Encoder },
+         { artist(), KnownField::Artist },
-        { encoderSettings(), KnownField::EncoderSettings }, { description(), KnownField::Description }, { label(), KnownField::RecordLabel },
+         { comment(), KnownField::Comment },
-        { performer(), KnownField::Performers }, { lyricist(), KnownField::Lyricist } });
+         { cover(), KnownField::Cover },
+         { date(), KnownField::Year },
+         { title(), KnownField::Title },
+         { genre(), KnownField::Genre },
+         { trackNumber(), KnownField::TrackPosition },
+         { diskNumber(), KnownField::DiskPosition },
+         { partNumber(), KnownField::PartNumber },
+         { composer(), KnownField::Composer },
+         { encoder(), KnownField::Encoder },
+         { encoderSettings(), KnownField::EncoderSettings },
+         { description(), KnownField::Description },
+         { grouping(), KnownField::Grouping },
+         { label(), KnownField::RecordLabel },
+         { performer(), KnownField::Performers },
+         { lyricist(), KnownField::Lyricist },
+         { albumArtist(), KnownField::AlbumArtist },
+    });
+    // clang-format on
     const auto knownField(fieldMap.find(id));
     return knownField != fieldMap.cend() ? knownField->second : KnownField::Invalid;
 }

vorbis/vorbiscommentids.h

@@ -38,6 +38,14 @@ constexpr TAG_PARSER_EXPORT const char *artist()
 {
     return "ARTIST";
 }
+constexpr TAG_PARSER_EXPORT const char *albumArtist()
+{
+    return "ALBUMARTIST";
+}
+constexpr TAG_PARSER_EXPORT const char *grouping()
+{
+    return "GROUPING";
+}
 constexpr TAG_PARSER_EXPORT const char *album()
 {
     return "ALBUM";