isom: Add MPEG4SYSTEMS dummy object type indication.

libavcodec/avcodec.h

@@ -372,6 +372,8 @@ enum CodecID {
 
     CODEC_ID_MPEG2TS= 0x20000, /**< _FAKE_ codec to indicate a raw MPEG-2 TS
                                 * stream (only used by libavformat) */
+    CODEC_ID_MPEG4SYSTEMS = 0x20001, /**< _FAKE_ codec to indicate a MPEG-4 Systems
+                                * stream (only used by libavformat) */
     CODEC_ID_FFMETADATA=0x21000,   ///< Dummy codec for streams containing only metadata information.
 };
 

libavformat/isom.c

@@ -61,6 +61,8 @@ const AVCodecTag ff_mp4_obj_type[] = {
     { CODEC_ID_VORBIS    , 0xDD }, /* non standard, gpac uses it */
     { CODEC_ID_DVD_SUBTITLE, 0xE0 }, /* non standard, see unsupported-embedded-subs-2.mp4 */
     { CODEC_ID_QCELP     , 0xE1 },
+    { CODEC_ID_MPEG4SYSTEMS, 0x01 },
+    { CODEC_ID_MPEG4SYSTEMS, 0x02 },
     { CODEC_ID_NONE      ,    0 },
 };