diff --git a/src/extractors/taglibextractor.h b/src/extractors/taglibextractor.h
--- a/src/extractors/taglibextractor.h
+++ b/src/extractors/taglibextractor.h
@@ -23,20 +23,6 @@
 
 #include "extractorplugin.h"
 
-namespace TagLib
-{
-    namespace ASF {
-        class Tag;
-    }
-    namespace ID3v2 {
-        class Tag;
-    }
-    namespace MP4 {
-        class Tag;
-    }
-    class PropertyMap;
-}
-
 namespace KFileMetaData
 {
 
@@ -52,13 +38,7 @@
 
     void extract(ExtractionResult* result) override;
     QStringList mimetypes() const override;
-    
-private:
 
-    void extractId3Tags(TagLib::ID3v2::Tag* Id3Tags, ExtractionResult* result);
-    void extractMp4Tags(TagLib::MP4::Tag* mp4Tags, ExtractionResult* result);
-    void extractAsfTags(TagLib::ASF::Tag* asfTags, ExtractionResult* result);
-    void readGenericProperties(const TagLib::PropertyMap &savedProperties, ExtractionResult* result);
 };
 
 }
diff --git a/src/extractors/taglibextractor.cpp b/src/extractors/taglibextractor.cpp
--- a/src/extractors/taglibextractor.cpp
+++ b/src/extractors/taglibextractor.cpp
@@ -47,10 +47,7 @@
 
 using namespace KFileMetaData;
 
-TagLibExtractor::TagLibExtractor(QObject* parent)
-    : ExtractorPlugin(parent)
-{
-}
+namespace {
 
 const QStringList supportedMimeTypes = {
     QStringLiteral("audio/flac"),
@@ -74,11 +71,6 @@
     QStringLiteral("audio/x-wavpack"),
 };
 
-QStringList TagLibExtractor::mimetypes() const
-{
-    return supportedMimeTypes;
-}
-
 void extractAudioProperties(TagLib::File* file, ExtractionResult* result)
 {
     TagLib::AudioProperties* audioProp = file->audioProperties();
@@ -102,7 +94,7 @@
     }
 }
 
-void TagLibExtractor::readGenericProperties(const TagLib::PropertyMap &savedProperties, ExtractionResult* result)
+void readGenericProperties(const TagLib::PropertyMap &savedProperties, ExtractionResult* result)
 {
     if (savedProperties.isEmpty()) {
         return;
@@ -260,7 +252,7 @@
     }
 }
 
-void TagLibExtractor::extractId3Tags(TagLib::ID3v2::Tag* Id3Tags, ExtractionResult* result)
+void extractId3Tags(TagLib::ID3v2::Tag* Id3Tags, ExtractionResult* result)
 {
     if (Id3Tags->isEmpty()) {
         return;
@@ -309,7 +301,7 @@
     }
 }
 
-void TagLibExtractor::extractMp4Tags(TagLib::MP4::Tag* mp4Tags, ExtractionResult* result)
+void extractMp4Tags(TagLib::MP4::Tag* mp4Tags, ExtractionResult* result)
 {
     if (mp4Tags->isEmpty()) {
         return;
@@ -327,7 +319,7 @@
     }
 }
 
-void TagLibExtractor::extractAsfTags(TagLib::ASF::Tag* asfTags, ExtractionResult* result)
+void extractAsfTags(TagLib::ASF::Tag* asfTags, ExtractionResult* result)
 {
     if (asfTags->isEmpty()) {
         return;
@@ -374,6 +366,18 @@
     }
 }
 
+} // anonymous namespace
+
+TagLibExtractor::TagLibExtractor(QObject* parent)
+    : ExtractorPlugin(parent)
+{
+}
+
+QStringList TagLibExtractor::mimetypes() const
+{
+    return supportedMimeTypes;
+}
+
 void TagLibExtractor::extract(ExtractionResult* result)
 {
     const QString fileUrl = result->inputUrl();