diff --git a/matroska/KaxBlock.h b/matroska/KaxBlock.h
index f9dbc987..96461972 100644
--- a/matroska/KaxBlock.h
+++ b/matroska/KaxBlock.h
@@ -198,7 +198,7 @@ class MATROSKA_DLL_API KaxInternalBlock : public libebml::EbmlBinary {
     /*!
       \note override this function to generate the Data/Size on the fly, unlike the usual binary elements
     */
-    libebml::filepos_t UpdateSize(ShouldWrite writeFilter = WriteSkipDefault, bool bForceRender = false) override;
+    libebml::filepos_t UpdateSize(const ShouldWrite & writeFilter = WriteSkipDefault, bool bForceRender = false) override;
     libebml::filepos_t ReadData(libebml::IOCallback & input, libebml::ScopeMode ReadFully = libebml::SCOPE_ALL_DATA) override;
 
     /*!
@@ -266,7 +266,7 @@ class MATROSKA_DLL_API KaxInternalBlock : public libebml::EbmlBinary {
 
     KaxCluster               *ParentCluster{nullptr};
 
-    libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter = WriteSkipDefault) override;
+    libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter = WriteSkipDefault) override;
 };
 
 class MATROSKA_DLL_API KaxBlock : public KaxInternalBlock {
@@ -342,11 +342,11 @@ DECLARE_MKX_BINARY_CONS(KaxBlockVirtual)
     /*!
       \note override this function to generate the Data/Size on the fly, unlike the usual binary elements
     */
-    libebml::filepos_t UpdateSize(ShouldWrite writeFilter = WriteSkipDefault, bool bForceRender = false) override;
+    libebml::filepos_t UpdateSize(const ShouldWrite & writeFilter = WriteSkipDefault, bool bForceRender = false) override;
 
     void SetParent(const KaxCluster & aParentCluster) {ParentCluster = &aParentCluster;}
 
-    libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+    libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 
     libebml::filepos_t ReadData(libebml::IOCallback & input, libebml::ScopeMode ReadFully = libebml::SCOPE_ALL_DATA) override;
 
diff --git a/matroska/KaxBlockData.h b/matroska/KaxBlockData.h
index 490d96db..83495bdb 100644
--- a/matroska/KaxBlockData.h
+++ b/matroska/KaxBlockData.h
@@ -26,7 +26,7 @@ DECLARE_MKX_SINTEGER_CONS(KaxReferenceBlock)
     /*!
       \brief override this method to compute the timestamp value
     */
-    libebml::filepos_t UpdateSize(ShouldWrite writeFilter = WriteSkipDefault, bool bForceRender = false) override;
+    libebml::filepos_t UpdateSize(const ShouldWrite & writeFilter = WriteSkipDefault, bool bForceRender = false) override;
 
     const KaxBlockBlob & RefBlock() const;
     void SetReferencedBlock(const KaxBlockBlob * aRefdBlock);
diff --git a/matroska/KaxSemantic.h b/matroska/KaxSemantic.h
index cb301cf4..34652cc8 100644
--- a/matroska/KaxSemantic.h
+++ b/matroska/KaxSemantic.h
@@ -87,12 +87,12 @@ DECLARE_MKX_UINTEGER(KaxClusterTimestamp)
 
 DECLARE_MKX_MASTER(KaxClusterSilentTracks)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER(KaxClusterSilentTrackNumber)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER(KaxClusterPosition)
@@ -121,7 +121,7 @@ DECLARE_MKX_UINTEGER_DEF(KaxReferencePriority)
 
 DECLARE_MKX_SINTEGER(KaxReferenceVirtual)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_BINARY(KaxCodecState)
@@ -132,57 +132,57 @@ DECLARE_MKX_SINTEGER(KaxDiscardPadding)
 
 DECLARE_MKX_MASTER(KaxSlices)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_MASTER(KaxTimeSlice)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER(KaxSliceLaceNumber)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER_DEF(KaxSliceFrameNumber)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER_DEF(KaxSliceBlockAddID)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER_DEF(KaxSliceDelay)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER_DEF(KaxSliceDuration)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_MASTER(KaxReferenceFrame)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER(KaxReferenceOffset)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER(KaxReferenceTimestamp)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_BINARY(KaxEncryptedBlock)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_MASTER(KaxTracks)
@@ -226,12 +226,12 @@ DECLARE_MKX_UINTEGER_DEF(KaxTrackFlagLacing)
 
 DECLARE_MKX_UINTEGER_DEF(KaxTrackMinCache)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER(KaxTrackMaxCache)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER(KaxTrackDefaultDuration)
@@ -242,12 +242,12 @@ DECLARE_MKX_UINTEGER(KaxTrackDefaultDecodedFieldDuration)
 
 DECLARE_MKX_FLOAT_DEF(KaxTrackTimestampScale)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_SINTEGER_DEF(KaxTrackOffset)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER_DEF(KaxMaxBlockAdditionID)
@@ -288,32 +288,32 @@ DECLARE_MKX_UNISTRING(KaxCodecName)
 
 DECLARE_MKX_UINTEGER(KaxTrackAttachmentLink)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UNISTRING(KaxCodecSettings)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_STRING(KaxCodecInfoURL)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_STRING(KaxCodecDownloadURL)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER_DEF(KaxCodecDecodeAll)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER(KaxTrackOverlay)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER_DEF(KaxCodecDelay)
@@ -351,7 +351,7 @@ DECLARE_MKX_UINTEGER_DEF(KaxVideoAlphaMode)
 
 DECLARE_MKX_UINTEGER(KaxOldStereoMode)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER(KaxVideoPixelWidth)
@@ -383,7 +383,7 @@ DECLARE_MKX_UINTEGER_DEF(KaxVideoDisplayUnit)
 
 DECLARE_MKX_UINTEGER_DEF(KaxVideoAspectRatio)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_BINARY_LENGTH(KaxVideoColourSpace, 4)
@@ -391,12 +391,12 @@ DECLARE_MKX_BINARY_LENGTH(KaxVideoColourSpace, 4)
 
 DECLARE_MKX_FLOAT(KaxVideoGamma)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_FLOAT(KaxVideoFrameRate)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_MASTER(KaxVideoColour)
@@ -506,7 +506,7 @@ DECLARE_MKX_UINTEGER_DEF(KaxAudioChannels)
 
 DECLARE_MKX_BINARY(KaxAudioPosition)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER(KaxAudioBitDepth)
@@ -538,27 +538,27 @@ DECLARE_MKX_UINTEGER(KaxTrackJoinUID)
 
 DECLARE_MKX_UINTEGER(KaxTrickTrackUID)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_BINARY_LENGTH(KaxTrickTrackSegmentUID, 16)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER_DEF(KaxTrickTrackFlag)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER(KaxTrickMasterTrackUID)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_BINARY_LENGTH(KaxTrickMasterTrackSegmentUID, 16)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_MASTER(KaxContentEncodings)
@@ -602,22 +602,22 @@ DECLARE_MKX_UINTEGER(KaxAESSettingsCipherMode)
 
 DECLARE_MKX_BINARY(KaxContentSignature)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_BINARY(KaxContentSigKeyID)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER_DEF(KaxContentSigAlgo)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER_DEF(KaxContentSigHashAlgo)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER(KaxCueTime)
@@ -646,17 +646,17 @@ DECLARE_MKX_UINTEGER(KaxCueRefTime)
 
 DECLARE_MKX_UINTEGER(KaxCueRefCluster)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER_DEF(KaxCueRefNumber)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER_DEF(KaxCueRefCodecState)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_MASTER(KaxAttachments)
@@ -682,17 +682,17 @@ DECLARE_MKX_UINTEGER(KaxFileUID)
 
 DECLARE_MKX_BINARY(KaxFileReferral)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER(KaxFileUsedStartTime)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER(KaxFileUsedEndTime)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_MASTER(KaxChapters)
@@ -838,7 +838,7 @@ DECLARE_MKX_UINTEGER_DEF(KaxTagDefault)
 
 DECLARE_MKX_UINTEGER_DEF(KaxTagDefaultBogus)
 public:
-  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, const ShouldWrite & writeFilter) override;
 };
 
 DECLARE_MKX_UNISTRING(KaxTagString)
diff --git a/src/KaxBlock.cpp b/src/KaxBlock.cpp
index cb509924..79c0db33 100644
--- a/src/KaxBlock.cpp
+++ b/src/KaxBlock.cpp
@@ -201,7 +201,7 @@ LacingType KaxInternalBlock::GetBestLacingType() const {
   return LACING_EBML;
 }
 
-filepos_t KaxInternalBlock::UpdateSize(ShouldWrite, bool /* bForceRender */)
+filepos_t KaxInternalBlock::UpdateSize(const ShouldWrite &, bool /* bForceRender */)
 {
   LacingType LacingHere;
   assert(!EbmlBinary::GetBuffer()); // Data is not used for KaxInternalBlock
@@ -277,7 +277,7 @@ KaxBlockVirtual::~KaxBlockVirtual()
     SetBuffer( nullptr, 0 );
 }
 
-filepos_t KaxBlockVirtual::UpdateSize(ShouldWrite, bool /* bForceRender */)
+filepos_t KaxBlockVirtual::UpdateSize(const ShouldWrite &, bool /* bForceRender */)
 {
   assert(TrackNumber < 0x4000);
   binary *cursor = EbmlBinary::GetBuffer();
@@ -305,7 +305,7 @@ filepos_t KaxBlockVirtual::UpdateSize(ShouldWrite, bool /* bForceRender */)
   \todo more optimisation is possible (render the Block head and don't copy the buffer in memory, care should be taken with the allocation of Data)
   \todo the actual timestamp to write should be retrieved from the Cluster from here
 */
-filepos_t KaxInternalBlock::RenderData(IOCallback & output, bool /* bForceRender */, ShouldWrite)
+filepos_t KaxInternalBlock::RenderData(IOCallback & output, bool /* bForceRender */, const ShouldWrite &)
 {
   if (myBuffers.empty())
     return 0;
diff --git a/src/KaxBlockData.cpp b/src/KaxBlockData.cpp
index e69947e7..a1645577 100644
--- a/src/KaxBlockData.cpp
+++ b/src/KaxBlockData.cpp
@@ -47,7 +47,7 @@ void KaxReferenceBlock::FreeBlob()
   RefdBlock = nullptr;
 }
 
-filepos_t KaxReferenceBlock::UpdateSize(ShouldWrite writeFilter, bool bForceRender)
+filepos_t KaxReferenceBlock::UpdateSize(const ShouldWrite & writeFilter, bool bForceRender)
 {
   if (!bTimestampSet) {
     assert(RefdBlock);
diff --git a/src/KaxSemantic.cpp b/src/KaxSemantic.cpp
index bd384f08..18384aa0 100644
--- a/src/KaxSemantic.cpp
+++ b/src/KaxSemantic.cpp
@@ -737,232 +737,232 @@ DEFINE_MKX_UINTEGER_DEF(KaxTagDefaultBogus, 0x44B4, 2, KaxTagSimple, "TagDefault
 DEFINE_MKX_UNISTRING(KaxTagString, 0x4487, 2, KaxTagSimple, "TagString", VERSION_ALL_MATROSKA)
 DEFINE_MKX_BINARY (KaxTagBinary, 0x4485, 2, KaxTagSimple, "TagBinary", VERSION_ALL_MATROSKA)
 
-libebml::filepos_t KaxClusterSilentTracks::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxClusterSilentTracks::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxClusterSilentTrackNumber::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxClusterSilentTrackNumber::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxBlockVirtual::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxBlockVirtual::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxReferenceVirtual::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxReferenceVirtual::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxSlices::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxSlices::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxTimeSlice::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxTimeSlice::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxSliceLaceNumber::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxSliceLaceNumber::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxSliceFrameNumber::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxSliceFrameNumber::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxSliceBlockAddID::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxSliceBlockAddID::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxSliceDelay::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxSliceDelay::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxSliceDuration::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxSliceDuration::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxReferenceFrame::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxReferenceFrame::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxReferenceOffset::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxReferenceOffset::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxReferenceTimestamp::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxReferenceTimestamp::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxEncryptedBlock::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxEncryptedBlock::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxTrackMinCache::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxTrackMinCache::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxTrackMaxCache::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxTrackMaxCache::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxTrackTimestampScale::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxTrackTimestampScale::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxTrackOffset::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxTrackOffset::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxTrackAttachmentLink::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxTrackAttachmentLink::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxCodecSettings::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxCodecSettings::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxCodecInfoURL::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxCodecInfoURL::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxCodecDownloadURL::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxCodecDownloadURL::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxCodecDecodeAll::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxCodecDecodeAll::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxTrackOverlay::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxTrackOverlay::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxOldStereoMode::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxOldStereoMode::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxVideoAspectRatio::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxVideoAspectRatio::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxVideoGamma::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxVideoGamma::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxVideoFrameRate::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxVideoFrameRate::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxAudioPosition::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxAudioPosition::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxTrickTrackUID::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxTrickTrackUID::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxTrickTrackSegmentUID::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxTrickTrackSegmentUID::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxTrickTrackFlag::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxTrickTrackFlag::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxTrickMasterTrackUID::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxTrickMasterTrackUID::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxTrickMasterTrackSegmentUID::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxTrickMasterTrackSegmentUID::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxContentSignature::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxContentSignature::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxContentSigKeyID::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxContentSigKeyID::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxContentSigAlgo::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxContentSigAlgo::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxContentSigHashAlgo::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxContentSigHashAlgo::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxCueRefCluster::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxCueRefCluster::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxCueRefNumber::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxCueRefNumber::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxCueRefCodecState::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxCueRefCodecState::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxFileReferral::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxFileReferral::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxFileUsedStartTime::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxFileUsedStartTime::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxFileUsedEndTime::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxFileUsedEndTime::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }
 
-libebml::filepos_t KaxTagDefaultBogus::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+libebml::filepos_t KaxTagDefaultBogus::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, const ShouldWrite & /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;
 }