diff --git a/src/common/chapter_parser_cue.cpp b/src/common/chapter_parser_cue.cpp
index 2f2a3674c..6fefb7479 100644
--- a/src/common/chapter_parser_cue.cpp
+++ b/src/common/chapter_parser_cue.cpp
@@ -374,7 +374,7 @@ parse_cue_chapters(mm_text_io_c *in,
 
   if (in->get_byte_order() == BO_NONE) {
     a.do_convert = true;
-    a.cc_utf8 = utf8_init(charset.c_str());
+    a.cc_utf8 = utf8_init(charset);
 
   } else {
     a.do_convert = false;
diff --git a/src/common/chapters.cpp b/src/common/chapters.cpp
index 1ba52859e..0d6a1bae8 100644
--- a/src/common/chapters.cpp
+++ b/src/common/chapters.cpp
@@ -214,7 +214,7 @@ parse_simple_chapters(mm_text_io_c *in,
 
   if (in->get_byte_order() == BO_NONE) {
     do_convert = true;
-    cc_utf8 = utf8_init(charset.c_str());
+    cc_utf8 = utf8_init(charset);
 
   } else
     do_convert = false;
diff --git a/src/common/common.cpp b/src/common/common.cpp
index f94c44fe8..5a1ac76be 100644
--- a/src/common/common.cpp
+++ b/src/common/common.cpp
@@ -541,12 +541,12 @@ add_kax_conv(const char *charset,
 }
 
 int
-utf8_init(const char *charset) {
+utf8_init(const string &charset) {
   string lc_charset;
   iconv_t ict_from_utf8, ict_to_utf8;
   int i;
 
-  if ((charset == NULL) || (*charset == 0)) {
+  if (charset == "") {
     setlocale(LC_CTYPE, "");
 #if defined(COMP_MINGW) || defined(COMP_MSC)
     lc_charset = "CP" + to_string(GetACP());
diff --git a/src/common/common.h b/src/common/common.h
index 15139b72f..2f02d869b 100644
--- a/src/common/common.h
+++ b/src/common/common.h
@@ -152,7 +152,7 @@ void MTX_DLL_API put_uint64_be(void *buf, uint64_t value);
 
 extern int MTX_DLL_API cc_local_utf8;
 
-int MTX_DLL_API utf8_init(const char *charset);
+int MTX_DLL_API utf8_init(const string &charset);
 void MTX_DLL_API utf8_done();
 char *MTX_DLL_API to_utf8_c(int handle, const char *local);
 inline char *
diff --git a/src/extract/mkvextract.cpp b/src/extract/mkvextract.cpp
index 3bb15f9a0..f0102a1af 100644
--- a/src/extract/mkvextract.cpp
+++ b/src/extract/mkvextract.cpp
@@ -252,7 +252,7 @@ parse_args(int argc,
       if ((i + 1) >= argc)
         mxerror(_("'-c' lacks a charset.\n"));
 
-      conv_handle = utf8_init(argv[i + 1]);
+      conv_handle = utf8_init(argv[i + 1] == NULL ? "" : argv[i + 1]);
       sub_charset = argv[i + 1];
       i++;
 
@@ -405,7 +405,7 @@ main(int argc,
 #endif
 
   srand(time(NULL));
-  utf8_init(NULL);
+  utf8_init("");
   conv_utf8 = utf8_init("UTF-8");
 
   xml_element_map_init();
diff --git a/src/info/mkvinfo.cpp b/src/info/mkvinfo.cpp
index 30af9fbe7..baff652e7 100644
--- a/src/info/mkvinfo.cpp
+++ b/src/info/mkvinfo.cpp
@@ -1891,7 +1891,7 @@ setup() {
   textdomain("mkvtoolnix");
 #endif
 
-  cc_local_utf8 = utf8_init(NULL);
+  cc_local_utf8 = utf8_init("");
 
   xml_element_map_init();
 }
diff --git a/src/input/r_ssa.cpp b/src/input/r_ssa.cpp
index 41717753b..b32f4d25d 100644
--- a/src/input/r_ssa.cpp
+++ b/src/input/r_ssa.cpp
@@ -82,7 +82,8 @@ ssa_reader_c::ssa_reader_c(track_info_c *nti)
     for (i = 0; i < ti->sub_charsets->size(); i++)
       if ((*ti->sub_charsets)[i].id == 0) {
         sub_charset_found = true;
-        cc_utf8 = utf8_init((*ti->sub_charsets)[i].language);
+        cc_utf8 = utf8_init((*ti->sub_charsets)[i].language == NULL ? "" :
+                            (*ti->sub_charsets)[i].language);
         break;
       }
 
@@ -90,7 +91,7 @@ ssa_reader_c::ssa_reader_c(track_info_c *nti)
       if (mm_io->get_byte_order() != BO_NONE)
         cc_utf8 = utf8_init("UTF-8");
       else
-        cc_utf8 = utf8_init(ti->sub_charset);
+        cc_utf8 = utf8_init(ti->sub_charset == NULL ? "" : ti->sub_charset);
     }
 
     ti->id = 0;                 // ID for this track.
diff --git a/src/merge/mkvmerge.cpp b/src/merge/mkvmerge.cpp
index bfc7c361a..dfa33b5b3 100644
--- a/src/merge/mkvmerge.cpp
+++ b/src/merge/mkvmerge.cpp
@@ -1417,6 +1417,7 @@ parse_args(vector<string> &args) {
                   "'--chapter-charset %s'.\n"), next_arg.c_str());
 
       chapter_charset = next_arg;
+      ti->chapter_charset = next_arg;
       sit++;
 
     } else if ((this_arg == "--cue-chapter-name-format")) {
@@ -1829,7 +1830,7 @@ handle_args(int argc,
       if (!strcmp(argv[i], "--command-line-charset")) {
         if ((i + 1) == argc)
           mxerror(_("'--command-line-charset' is missing its argument.\n"));
-        cc_command_line = utf8_init(argv[i + 1]);
+        cc_command_line = utf8_init(argv[i + 1] == NULL ? "" : argv[i + 1]);
         i++;
       } else
         args.push_back(to_utf8(cc_command_line, argv[i]));
diff --git a/src/merge/output_control.cpp b/src/merge/output_control.cpp
index ed859a71b..8b9c68534 100644
--- a/src/merge/output_control.cpp
+++ b/src/merge/output_control.cpp
@@ -1766,7 +1766,7 @@ setup() {
 #endif
 
   srand(time(NULL));
-  cc_local_utf8 = utf8_init(NULL);
+  cc_local_utf8 = utf8_init("");
 
   cluster_helper = new cluster_helper_c();
 
diff --git a/src/merge/pr_generic.cpp b/src/merge/pr_generic.cpp
index 0c644fc07..15cd0cf32 100644
--- a/src/merge/pr_generic.cpp
+++ b/src/merge/pr_generic.cpp
@@ -1378,6 +1378,8 @@ track_info_c::operator =(const track_info_c &src) {
   no_attachments = src.no_attachments;
   no_tags = src.no_tags;
 
+  chapter_charset = src.chapter_charset;
+
   avi_block_align = src.avi_block_align;
   avi_samples_per_sec = src.avi_samples_per_sec;
   avi_avg_bytes_per_sec = src.avi_avg_bytes_per_sec;
diff --git a/src/merge/pr_generic.h b/src/merge/pr_generic.h
index 3e8391b14..1207a7a29 100644
--- a/src/merge/pr_generic.h
+++ b/src/merge/pr_generic.h
@@ -223,6 +223,10 @@ public:
 
   bool no_chapters, no_attachments, no_tags;
 
+  // Some file formats can contain chapters, but for some the charset
+  // cannot be identified unambiguously (*cough* OGM *cough*).
+  string chapter_charset;
+
   // The following variables are needed for the broken way of
   // syncing audio in AVIs: by prepending it with trash. Thanks to
   // the nandub author for this really, really sucky implementation.
diff --git a/src/mmg/mmg.cpp b/src/mmg/mmg.cpp
index 86b7f659d..f05b5caf8 100644
--- a/src/mmg/mmg.cpp
+++ b/src/mmg/mmg.cpp
@@ -1743,7 +1743,7 @@ mmg_app::OnInit() {
   uint32_t i;
   wxString k, v;
 
-  cc_local_utf8 = utf8_init(NULL);
+  cc_local_utf8 = utf8_init("");
   xml_element_map_init();
 
   cfg = new wxConfig(wxT("mkvmergeGUI"));
diff --git a/src/output/p_textsubs.cpp b/src/output/p_textsubs.cpp
index aa2eb6eae..df0add451 100644
--- a/src/output/p_textsubs.cpp
+++ b/src/output/p_textsubs.cpp
@@ -38,7 +38,7 @@ textsubs_packetizer_c::textsubs_packetizer_c(generic_reader_c *nreader,
   recode = nrecode;
   if (recode) {
     if ((ti->sub_charset != NULL) || !is_utf8)
-      cc_utf8 = utf8_init(ti->sub_charset);
+      cc_utf8 = utf8_init(ti->sub_charset == NULL ? "" : ti->sub_charset);
     else
       cc_utf8 = utf8_init("UTF-8");
   }