[FFmpeg-devel] [PATCH] avformat/asfenc: write group_mutual_exclusion_objects on multiple languages

[Marton Balint]

Improves streaming compatibility with Windows Media Services. Also tested for
compatilbility in Windows Media Player, Windows Media ASF Viewer and VLC.

Signed-off-by: Marton Balint <cus at passwd.hu>
---
 libavformat/asf.c    |  8 ++++++++
 libavformat/asf.h    |  2 ++
 libavformat/asfenc.c | 15 +++++++++++++++
 3 files changed, 25 insertions(+)

diff --git a/libavformat/asf.c b/libavformat/asf.c
index 455ca4d..719cae9 100644
--- a/libavformat/asf.c
+++ b/libavformat/asf.c
@@ -147,6 +147,14 @@ const ff_asf_guid ff_asf_extended_stream_properties_object = {
     0xcb, 0xa5, 0xe6, 0x14, 0x72, 0xc6, 0x32, 0x43, 0x83, 0x99, 0xa9, 0x69, 0x52, 0x06, 0x5b, 0x5a
 };
 
+const ff_asf_guid ff_asf_group_mutual_exclusion_object = {
+    0x40, 0x5a, 0x46, 0xd1, 0x79, 0x5a, 0x38, 0x43, 0xb7, 0x1b, 0xe3, 0x6b, 0x8f, 0xd6, 0xc2, 0x49
+};
+
+const ff_asf_guid ff_asf_mutex_language = {
+    0x00, 0x2a, 0xe2, 0xd6, 0xda, 0x35, 0xd1, 0x11, 0x90, 0x34, 0x00, 0xa0, 0xc9, 0x03, 0x49, 0xbe
+};
+
 /* List of official tags at http://msdn.microsoft.com/en-us/library/dd743066(VS.85).aspx */
 const AVMetadataConv ff_asf_metadata_conv[] = {
     { "WM/AlbumArtist",          "album_artist"     },
diff --git a/libavformat/asf.h b/libavformat/asf.h
index 914ddef..43288dd 100644
--- a/libavformat/asf.h
+++ b/libavformat/asf.h
@@ -100,6 +100,8 @@ extern const ff_asf_guid ff_asf_content_encryption;
 extern const ff_asf_guid ff_asf_ext_content_encryption;
 extern const ff_asf_guid ff_asf_digital_signature;
 extern const ff_asf_guid ff_asf_extended_stream_properties_object;
+extern const ff_asf_guid ff_asf_group_mutual_exclusion_object;
+extern const ff_asf_guid ff_asf_mutex_language;
 
 extern const AVMetadataConv ff_asf_metadata_conv[];
 
diff --git a/libavformat/asfenc.c b/libavformat/asfenc.c
index a6a8242..3317133 100644
--- a/libavformat/asfenc.c
+++ b/libavformat/asfenc.c
@@ -396,6 +396,7 @@ static int asf_write_header1(AVFormatContext *s, int64_t file_size,
     int64_t header_offset, cur_pos, hpos;
     int bit_rate;
     int64_t duration;
+    int language_counts[128] = { 0 };
 
     ff_metadata_conv(&s->metadata, ff_asf_metadata_conv, NULL);
 
@@ -447,6 +448,7 @@ static int asf_write_header1(AVFormatContext *s, int64_t file_size,
                     asf->streams[n].stream_language_index = asf->nb_languages;
                     asf->nb_languages++;
                 }
+                language_counts[asf->streams[n].stream_language_index]++;
             }
         } else {
             asf->streams[n].stream_language_index = 128;
@@ -496,6 +498,19 @@ static int asf_write_header1(AVFormatContext *s, int64_t file_size,
         }
         end_header(pb, hpos2);
 
+        if (asf->nb_languages > 1) {
+            hpos2 = put_header(pb, &ff_asf_group_mutual_exclusion_object);
+            ff_put_guid(pb, &ff_asf_mutex_language);
+            avio_wl16(pb, asf->nb_languages);
+            for (i = 0; i < asf->nb_languages; i++) {
+                avio_wl16(pb, language_counts[i]);
+                for (n = 0; n < s->nb_streams; n++)
+                    if (asf->streams[n].stream_language_index == i)
+                        avio_wl16(pb, n + 1);
+            }
+            end_header(pb, hpos2);
+        }
+
         for (n = 0; n < s->nb_streams; n++) {
             int64_t es_pos;
             if (asf->streams[n].stream_language_index > 127)
-- 
2.6.2