@@ -283,12 +283,24 @@ static void mpegts_write_pmt(AVFormatContext *s, MpegTSService *service)

         /* write optional descriptors here */

         switch(st->codec->codec_type) {

         case AVMEDIA_TYPE_AUDIO:

-            if (lang && strlen(lang->value) == 3) {

+            if (lang) {

+                char *p;

+                char *next = lang->value;

+                uint8_t *len_ptr;

+

                 *q++ = 0x0a; /* ISO 639 language descriptor */

-                *q++ = 4;

-                *q++ = lang->value[0];

-                *q++ = lang->value[1];

-                *q++ = lang->value[2];

+                len_ptr = q++;

+                *len_ptr = 0;

+

+                for (p = lang->value; next && *len_ptr < 255 / 4 * 4; p = next + 1) {

+                    next = strchr(p, ',');

+                    if (strlen(p) != 3 && (!next || next != p + 3))

+                        continue; /* not a 3-letter code */

+

+                    *q++ = *p++;

+                    *q++ = *p++;

+                    *q++ = *p++;

+

                 if (st->disposition & AV_DISPOSITION_CLEAN_EFFECTS)

                     *q++ = 0x01;

                 else if (st->disposition & AV_DISPOSITION_HEARING_IMPAIRED)

@@ -297,6 +309,12 @@ static void mpegts_write_pmt(AVFormatContext *s, MpegTSService *service)

                     *q++ = 0x03;

                 else

                     *q++ = 0; /* undefined type */

+

+                    *len_ptr += 4;

+                }

+

+                if (*len_ptr == 0)

+                    q -= 2; /* no language codes were written */

             }

             break;

         case AVMEDIA_TYPE_SUBTITLE: