diff --git a/FFmpegSource2/ffavsfilters.cpp b/FFmpegSource2/ffavsfilters.cpp
index db33247df..d059d0a3b 100644
--- a/FFmpegSource2/ffavsfilters.cpp
+++ b/FFmpegSource2/ffavsfilters.cpp
@@ -42,9 +42,10 @@ AVSValue __cdecl CreateFFIndex(AVSValue Args, void* UserData, IScriptEnvironment
 
 	const char *Source = Args[0].AsString();
 	const char *CacheFile = Args[1].AsString("");
-	int TrackMask = Args[2].AsInt(0);
-	const char *AudioFile = Args[3].AsString("");
-	bool OverWrite = Args[4].AsBool(false);
+	int IndexMask = Args[2].AsInt(0);
+	int DumpMask = Args[3].AsInt(0);
+	const char *AudioFile = Args[4].AsString("");
+	bool OverWrite = Args[5].AsBool(false);
 
 	std::string DefaultCache(Source);
 	DefaultCache.append(".ffindex");
@@ -61,7 +62,7 @@ AVSValue __cdecl CreateFFIndex(AVSValue Args, void* UserData, IScriptEnvironment
 
 	FrameIndex *Index;
 	if (OverWrite || !(Index = FFMS_ReadIndex(CacheFile, ErrorMsg, MsgSize))) {
-		if (!(Index = FFMS_MakeIndex(Source, TrackMask, AudioFile, NULL, NULL, ErrorMsg, MsgSize)))
+		if (!(Index = FFMS_MakeIndex(Source, IndexMask, DumpMask, AudioFile, NULL, NULL, ErrorMsg, MsgSize)))
 			Env->ThrowError("FFIndex: %s", ErrorMsg);
 		if (FFMS_WriteIndex(CacheFile, Index, ErrorMsg, MsgSize)) {
 			FFMS_DestroyFrameIndex(Index);
@@ -118,7 +119,7 @@ AVSValue __cdecl CreateFFVideoSource(AVSValue Args, void* UserData, IScriptEnvir
 	FrameIndex *Index;
 	if (Cache) {
 		if (!(Index = FFMS_ReadIndex(CacheFile, ErrorMsg, MsgSize))) {
-			if (!(Index = FFMS_MakeIndex(Source, 0, NULL, NULL, NULL, ErrorMsg, MsgSize)))
+			if (!(Index = FFMS_MakeIndex(Source, 0, 0, NULL, NULL, NULL, ErrorMsg, MsgSize)))
 				Env->ThrowError("FFVideoSource: %s", ErrorMsg);
 
 			if (Cache)
@@ -175,7 +176,7 @@ AVSValue __cdecl CreateFFAudioSource(AVSValue Args, void* UserData, IScriptEnvir
 	FrameIndex *Index;
 	if (Cache) {
 		if (!(Index = FFMS_ReadIndex(CacheFile, ErrorMsg, MsgSize))) {
-			if (!(Index = FFMS_MakeIndex(Source, -1, CacheFile, NULL, NULL, ErrorMsg, MsgSize)))
+			if (!(Index = FFMS_MakeIndex(Source, -1, 0, CacheFile, NULL, NULL, ErrorMsg, MsgSize)))
 				Env->ThrowError("FFAudioSource: %s", ErrorMsg);
 
 			if (Cache)
@@ -208,7 +209,7 @@ AVSValue __cdecl CreateSWScale(AVSValue Args, void* UserData, IScriptEnvironment
 }
 
 extern "C" __declspec(dllexport) const char* __stdcall AvisynthPluginInit2(IScriptEnvironment* Env) {
-    Env->AddFunction("FFIndex", "[source]s[cachefile]s[trackmask]i[audiofile]s[overwrite]b", CreateFFIndex, 0);
+    Env->AddFunction("FFIndex", "[source]s[cachefile]s[indexmask]i[dumpmask]i[audiofile]s[overwrite]b", CreateFFIndex, 0);
     Env->AddFunction("FFVideoSource", "[source]s[track]i[cache]b[cachefile]s[pp]s[threads]i[timecodes]s[seekmode]i", CreateFFVideoSource, 0);
     Env->AddFunction("FFAudioSource", "[source]s[track]i[cache]b[cachefile]s", CreateFFAudioSource, 0);
 	Env->AddFunction("FFPP", "c[pp]s", CreateFFPP, 0);
diff --git a/FFmpegSource2/ffms.cpp b/FFmpegSource2/ffms.cpp
index bc48d1b7e..645402022 100644
--- a/FFmpegSource2/ffms.cpp
+++ b/FFmpegSource2/ffms.cpp
@@ -163,8 +163,8 @@ FFMS_API(int) FFMS_WriteTimecodes(FrameInfoVector *FIV, const char *TimecodeFile
 	return FIV->WriteTimecodes(TimecodeFile, ErrorMsg, MsgSize);
 }
 
-FFMS_API(FrameIndex *) FFMS_MakeIndex(const char *SourceFile, int AudioTrackMask, const char *AudioFile, IndexCallback IP, void *Private, char *ErrorMsg, unsigned MsgSize) {
-	return MakeIndex(SourceFile, AudioTrackMask, AudioFile, IP, Private, ErrorMsg, MsgSize);
+FFMS_API(FrameIndex *) FFMS_MakeIndex(const char *SourceFile, int IndexMask, int DumpMask, const char *AudioFile, IndexCallback IP, void *Private, char *ErrorMsg, unsigned MsgSize) {
+	return MakeIndex(SourceFile, IndexMask, DumpMask, AudioFile, IP, Private, ErrorMsg, MsgSize);
 }
 
 FFMS_API(FrameIndex *) FFMS_ReadIndex(const char *IndexFile, char *ErrorMsg, unsigned MsgSize) {
diff --git a/FFmpegSource2/ffms.h b/FFmpegSource2/ffms.h
index 5f4eec225..bf544f64d 100644
--- a/FFmpegSource2/ffms.h
+++ b/FFmpegSource2/ffms.h
@@ -182,7 +182,7 @@ FFMS_API(int) FFMS_FrameFromDTS(FrameInfoVector *FIV, int64_t DTS, char *ErrorMs
 FFMS_API(int) FFMS_ClosestFrameFromDTS(FrameInfoVector *FIV, int64_t DTS, char *ErrorMsg, unsigned MsgSize);
 FFMS_API(const TrackTimeBase *) FFMS_GetTimeBase(FrameInfoVector *FIV, char *ErrorMsg, unsigned MsgSize);
 FFMS_API(int) FFMS_WriteTimecodes(FrameInfoVector *FIV, const char *TimecodeFile, char *ErrorMsg, unsigned MsgSize);
-FFMS_API(FrameIndex *) FFMS_MakeIndex(const char *SourceFile, int AudioTrackMask, const char *AudioFile, IndexCallback IP, void *Private, char *ErrorMsg, unsigned MsgSize);
+FFMS_API(FrameIndex *) FFMS_MakeIndex(const char *SourceFile, int IndexMask, int DumpMask, const char *AudioFile, IndexCallback IP, void *Private, char *ErrorMsg, unsigned MsgSize);
 FFMS_API(FrameIndex *) FFMS_ReadIndex(const char *IndexFile, char *ErrorMsg, unsigned MsgSize);
 FFMS_API(int) FFMS_WriteIndex(const char *IndexFile, FrameIndex *TrackIndices, char *ErrorMsg, unsigned MsgSize);
 
diff --git a/FFmpegSource2/indexing.cpp b/FFmpegSource2/indexing.cpp
index 208b1f85d..4de60e85c 100644
--- a/FFmpegSource2/indexing.cpp
+++ b/FFmpegSource2/indexing.cpp
@@ -129,7 +129,7 @@ int WriteIndex(const char *IndexFile, FrameIndex *TrackIndices, char *ErrorMsg,
 	return 0;
 }
 
-static FrameIndex *MakeMatroskaIndex(const char *SourceFile, int AudioTrackMask, const char *AudioFile, IndexCallback IP, void *Private, char *ErrorMsg, unsigned MsgSize) {
+static FrameIndex *MakeMatroskaIndex(const char *SourceFile, int IndexMask, int DumpMask, const char *AudioFile, IndexCallback IP, void *Private, char *ErrorMsg, unsigned MsgSize) {
 	MatroskaFile *MF;
 	char ErrorMessage[256];
 	MatroskaReaderContext MC;
@@ -161,7 +161,7 @@ static FrameIndex *MakeMatroskaIndex(const char *SourceFile, int AudioTrackMask,
 	IndexMemory IM = IndexMemory(mkv_GetNumTracks(MF), db, AudioContexts);
 
 	for (unsigned int i = 0; i < mkv_GetNumTracks(MF); i++) {
-		if (AudioTrackMask & (1 << i) && mkv_GetTrackInfo(MF, i)->Type == TT_AUDIO) {
+		if (IndexMask & (1 << i) && mkv_GetTrackInfo(MF, i)->Type == TT_AUDIO) {
 			AVCodecContext *AudioCodecContext = avcodec_alloc_context();
 			AudioCodecContext->extradata = (uint8_t *)mkv_GetTrackInfo(MF, i)->CodecPrivate;
 			AudioCodecContext->extradata_size = mkv_GetTrackInfo(MF, i)->CodecPrivateSize;
@@ -186,7 +186,8 @@ static FrameIndex *MakeMatroskaIndex(const char *SourceFile, int AudioTrackMask,
 					return NULL;
 			}
 		} else {
-			AudioTrackMask &= ~(1 << i);
+			IndexMask &= ~(1 << i);
+			DumpMask &= ~(1 << i);
 		}
 	}
 
@@ -220,7 +221,7 @@ static FrameIndex *MakeMatroskaIndex(const char *SourceFile, int AudioTrackMask,
 		if (mkv_GetTrackInfo(MF, Track)->Type == TT_VIDEO)
 			(*TrackIndices)[Track].push_back(FrameInfo(StartTime, (FrameFlags & FRAME_KF) != 0));
 
-		if (AudioTrackMask & (1 << Track)) {
+		if (IndexMask & (1 << Track)) {
 			ReadFrame(FilePos, FrameSize, AudioContexts[Track].CS, MC, ErrorMsg, MsgSize);
 			(*TrackIndices)[Track].push_back(FrameInfo(AudioContexts[Track].CurrentSample, FilePos, FrameSize, (FrameFlags & FRAME_KF) != 0));
 
@@ -241,7 +242,7 @@ static FrameIndex *MakeMatroskaIndex(const char *SourceFile, int AudioTrackMask,
 					Size -= Ret;
 					Data += Ret;
 				}
-				if (dbsize > 0) {
+				if (dbsize > 0 && (DumpMask & (1 << Track))) {
 					// Delay writer creation until after an audio frame has been decoded. This ensures that all parameters are known when writing the headers.
 					if (!AudioContexts[Track].W64W) {
 						char ABuf[50];
@@ -265,8 +266,9 @@ static FrameIndex *MakeMatroskaIndex(const char *SourceFile, int AudioTrackMask,
 	return TrackIndices;
 }
 
-FrameIndex *MakeIndex(const char *SourceFile, int AudioTrackMask, const char *AudioFile, IndexCallback IP, void *Private, char *ErrorMsg, unsigned MsgSize) {
+FrameIndex *MakeIndex(const char *SourceFile, int IndexMask, int DumpMask, const char *AudioFile, IndexCallback IP, void *Private, char *ErrorMsg, unsigned MsgSize) {
 	AVFormatContext *FormatContext = NULL;
+	IndexMask |= DumpMask;
 
 	if (av_open_input_file(&FormatContext, SourceFile, NULL, 0, NULL) != 0) {
 		_snprintf(ErrorMsg, MsgSize, "Can't open '%s'", SourceFile);
@@ -276,7 +278,7 @@ FrameIndex *MakeIndex(const char *SourceFile, int AudioTrackMask, const char *Au
 	// Do matroska indexing instead?
 	if (!strcmp(FormatContext->iformat->name, "matroska")) {
 		av_close_input_file(FormatContext);
-		return MakeMatroskaIndex(SourceFile, AudioTrackMask, AudioFile, IP, Private, ErrorMsg, MsgSize);
+		return MakeMatroskaIndex(SourceFile, IndexMask, DumpMask, AudioFile, IP, Private, ErrorMsg, MsgSize);
 	}
 	
 	if (av_find_stream_info(FormatContext) < 0) {
@@ -292,7 +294,7 @@ FrameIndex *MakeIndex(const char *SourceFile, int AudioTrackMask, const char *Au
 	IndexMemory IM = IndexMemory(FormatContext->nb_streams, db, AudioContexts);
 
 	for (unsigned int i = 0; i < FormatContext->nb_streams; i++) {
-		if (AudioTrackMask & (1 << i) && FormatContext->streams[i]->codec->codec_type == CODEC_TYPE_AUDIO) {
+		if (IndexMask & (1 << i) && FormatContext->streams[i]->codec->codec_type == CODEC_TYPE_AUDIO) {
 			AVCodecContext *AudioCodecContext = FormatContext->streams[i]->codec;
 
 			AVCodec *AudioCodec = avcodec_find_decoder(AudioCodecContext->codec_id);
@@ -306,7 +308,8 @@ FrameIndex *MakeIndex(const char *SourceFile, int AudioTrackMask, const char *Au
 				return NULL;
 			}
 		} else {
-			AudioTrackMask &= ~(1 << i);
+			IndexMask &= ~(1 << i);
+			DumpMask &= ~(1 << i);
 		}
 	}
 
@@ -335,7 +338,7 @@ FrameIndex *MakeIndex(const char *SourceFile, int AudioTrackMask, const char *Au
 		if (FormatContext->streams[Packet.stream_index]->codec->codec_type == CODEC_TYPE_VIDEO)
 			(*TrackIndices)[Packet.stream_index].push_back(FrameInfo(Packet.dts, (Packet.flags & PKT_FLAG_KEY) ? 1 : 0));
 
-		if (AudioTrackMask & (1 << Packet.stream_index)) {
+		if (IndexMask & (1 << Packet.stream_index)) {
 				AVCodecContext *AudioCodecContext = FormatContext->streams[Packet.stream_index]->codec;
 				int Size = Packet.size;
 				uint8_t *Data = Packet.data;
@@ -354,7 +357,7 @@ FrameIndex *MakeIndex(const char *SourceFile, int AudioTrackMask, const char *Au
 						Data += Ret;
 					}
 
-					if (dbsize > 0) {
+					if (dbsize > 0 && (DumpMask & (1 << Packet.stream_index))) {
 						// Delay writer creation until after an audio frame has been decoded. This ensures that all parameters are known when writing the headers.
 						if (!AudioContexts[Packet.stream_index].W64W) {
 							char ABuf[50];
diff --git a/FFmpegSource2/indexing.h b/FFmpegSource2/indexing.h
index d8a13fb3d..87f807fc0 100644
--- a/FFmpegSource2/indexing.h
+++ b/FFmpegSource2/indexing.h
@@ -62,7 +62,7 @@ public:
 	int Decoder;
 };
 
-FrameIndex *MakeIndex(const char *SourceFile, int AudioTrackMask, const char *AudioFile, IndexCallback IP, void *Private, char *ErrorMsg, unsigned MsgSize);
+FrameIndex *MakeIndex(const char *SourceFile, int IndexMask, int DumpMask, const char *AudioFile, IndexCallback IP, void *Private, char *ErrorMsg, unsigned MsgSize);
 FrameIndex *ReadIndex(const char *IndexFile, char *ErrorMsg, unsigned MsgSize);
 int WriteIndex(const char *IndexFile, FrameIndex *TrackIndices, char *ErrorMsg, unsigned MsgSize);