diff --git a/ChangeLog b/ChangeLog
index b9f2b726..d4ec62cc 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2012-01-05  Erik de Castro Lopo  <erikd AT mega-nerd DOT com>
+
+    * src/aiff.c src/wav.c src/common.h
+    Refactor common code into src/common.h.
+
 2012-01-04  Erik de Castro Lopo  <erikd AT mega-nerd DOT com>
 
     * programs/sndfile-cmp.c
diff --git a/src/aiff.c b/src/aiff.c
index fb9b6335..6e7ca2a5 100644
--- a/src/aiff.c
+++ b/src/aiff.c
@@ -1,5 +1,5 @@
 /*
-** Copyright (C) 1999-2011 Erik de Castro Lopo <erikd@mega-nerd.com>
+** Copyright (C) 1999-2012 Erik de Castro Lopo <erikd@mega-nerd.com>
 ** Copyright (C) 2005 David Viens <davidv@plogue.com>
 **
 ** This program is free software; you can redistribute it and/or modify
@@ -1750,20 +1750,9 @@ aiff_read_chanmap (SF_PRIVATE * psf, unsigned dword)
 /*==============================================================================
 */
 
-static int
-aiff_id_to_marker (const SF_CHUNK_INFO * chunk_info)
-{	const unsigned char * cptr ;
-
-	if (chunk_info->id_size != 4)
-		return 0 ;
-
-	cptr = (const unsigned char *) chunk_info->id ;
-	return (cptr [3] << 24) + (cptr [2] << 16) + (cptr [1] << 8) + cptr [0] ;
-} /* aiff_id_to_marker */
-
 static int
 aiff_set_chunk (SF_PRIVATE *psf, const SF_CHUNK_INFO * chunk_info)
-{	int marker = aiff_id_to_marker (chunk_info) ;
+{	int marker = fourcc_to_marker (chunk_info) ;
 
 	return psf_save_write_chunk (&psf->wchunks, marker, chunk_info) ;
 } /* aiff_set_chunk */
@@ -1771,7 +1760,7 @@ aiff_set_chunk (SF_PRIVATE *psf, const SF_CHUNK_INFO * chunk_info)
 
 static int
 aiff_get_chunk_size (SF_PRIVATE *psf, SF_CHUNK_INFO * chunk_info)
-{	int indx, marker = aiff_id_to_marker (chunk_info) ;
+{	int indx, marker = fourcc_to_marker (chunk_info) ;
 
 	if ((indx = psf_find_read_chunk (&psf->rchunks, marker)) < 0)
 		return SFE_UNKNOWN_CHUNK ;
@@ -1783,7 +1772,7 @@ aiff_get_chunk_size (SF_PRIVATE *psf, SF_CHUNK_INFO * chunk_info)
 
 static int
 aiff_get_chunk_data (SF_PRIVATE *psf, SF_CHUNK_INFO * chunk_info)
-{	int indx, marker = aiff_id_to_marker (chunk_info) ;
+{	int indx, marker = fourcc_to_marker (chunk_info) ;
 	sf_count_t pos ;
 
 	if ((indx = psf_find_read_chunk (&psf->rchunks, marker)) < 0)
diff --git a/src/common.h b/src/common.h
index 3b3cc543..1fb0578a 100644
--- a/src/common.h
+++ b/src/common.h
@@ -1,5 +1,5 @@
 /*
-** Copyright (C) 1999-2011 Erik de Castro Lopo <erikd@mega-nerd.com>
+** Copyright (C) 1999-2012 Erik de Castro Lopo <erikd@mega-nerd.com>
 **
 ** This program is free software; you can redistribute it and/or modify
 ** it under the terms of the GNU Lesser General Public License as published by
@@ -866,6 +866,17 @@ int		psf_save_write_chunk (WRITE_CHUNKS * pchk, int64_t marker, const SF_CHUNK_I
 int		psf_find_read_chunk (READ_CHUNKS * pchk, int64_t marker) ;
 int		psf_find_write_chunk (WRITE_CHUNKS * pchk, int64_t marker) ;
 
+static inline int
+fourcc_to_marker (const SF_CHUNK_INFO * chunk_info)
+{	const unsigned char * cptr ;
+
+	if (chunk_info->id_size != 4)
+		return 0 ;
+
+	cptr = (const unsigned char *) chunk_info->id ;
+	return (cptr [3] << 24) + (cptr [2] << 16) + (cptr [1] << 8) + cptr [0] ;
+} /* fourcc_to_marker */
+
 /*------------------------------------------------------------------------------------
 ** Functions that work like OpenBSD's strlcpy/strlcat to replace strncpy/strncat.
 **
diff --git a/src/wav.c b/src/wav.c
index 55bc6f12..a5676544 100644
--- a/src/wav.c
+++ b/src/wav.c
@@ -1,5 +1,5 @@
 /*
-** Copyright (C) 1999-2011 Erik de Castro Lopo <erikd@mega-nerd.com>
+** Copyright (C) 1999-2012 Erik de Castro Lopo <erikd@mega-nerd.com>
 ** Copyright (C) 2004-2005 David Viens <davidv@plogue.com>
 **
 ** This program is free software; you can redistribute it and/or modify
@@ -1829,20 +1829,9 @@ exif_subchunk_parse (SF_PRIVATE *psf, unsigned int length)
 /*==============================================================================
 */
 
-static int
-wav_id_to_marker (const SF_CHUNK_INFO * chunk_info)
-{	const unsigned char * cptr ;
-
-	if (chunk_info->id_size != 4)
-		return 0 ;
-
-	cptr = (const unsigned char *) chunk_info->id ;
-	return (cptr [3] << 24) + (cptr [2] << 16) + (cptr [1] << 8) + cptr [0] ;
-} /* wav_id_to_marker */
-
 static int
 wav_set_chunk (SF_PRIVATE *psf, const SF_CHUNK_INFO * chunk_info)
-{	int marker = wav_id_to_marker (chunk_info) ;
+{	int marker = fourcc_to_marker (chunk_info) ;
 
 	return psf_save_write_chunk (&psf->wchunks, marker, chunk_info) ;
 } /* wav_set_chunk */
@@ -1850,7 +1839,7 @@ wav_set_chunk (SF_PRIVATE *psf, const SF_CHUNK_INFO * chunk_info)
 
 static int
 wav_get_chunk_size (SF_PRIVATE *psf, SF_CHUNK_INFO * chunk_info)
-{	int indx, marker = wav_id_to_marker (chunk_info) ;
+{	int indx, marker = fourcc_to_marker (chunk_info) ;
 
 	if ((indx = psf_find_read_chunk (&psf->rchunks, marker)) < 0)
 		return SFE_UNKNOWN_CHUNK ;
@@ -1862,7 +1851,7 @@ wav_get_chunk_size (SF_PRIVATE *psf, SF_CHUNK_INFO * chunk_info)
 
 static int
 wav_get_chunk_data (SF_PRIVATE *psf, SF_CHUNK_INFO * chunk_info)
-{	int indx, marker = wav_id_to_marker (chunk_info) ;
+{	int indx, marker = fourcc_to_marker (chunk_info) ;
 	sf_count_t pos ;
 
 	if ((indx = psf_find_read_chunk (&psf->rchunks, marker)) < 0)