matroskaenc: require global header

fixes issue696

Originally committed as revision 15667 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/matroskaenc.c

@@ -903,6 +903,7 @@ AVOutputFormat matroska_muxer = {
     mkv_write_header,
     mkv_write_packet,
     mkv_write_trailer,
+    .flags = AVFMT_GLOBALHEADER,
     .codec_tag = (const AVCodecTag* const []){codec_bmp_tags, codec_wav_tags, 0},
     .subtitle_codec = CODEC_ID_TEXT,
 };
@@ -918,5 +919,6 @@ AVOutputFormat matroska_audio_muxer = {
     mkv_write_header,
     mkv_write_packet,
     mkv_write_trailer,
+    .flags = AVFMT_GLOBALHEADER,
     .codec_tag = (const AVCodecTag* const []){codec_wav_tags, 0},
 };

tests/libav.regression.ref

@@ -33,8 +33,8 @@ af78858062599fcbba049e4a02588a15 *./tests/data/b-libav.mov
 66a6584f9e83e8ea3af822a3ba71fbbe *./tests/data/b-libav.nut
 329264 ./tests/data/b-libav.nut
 ./tests/data/b-libav.nut CRC=0x400c29e9
-f108c91e3adadb39ce436c8836793045 *./tests/data/b-libav.mkv
-329860 ./tests/data/b-libav.mkv
+eae326ecf213a6f2ffb71a8a7afc5ef1 *./tests/data/b-libav.mkv
+329803 ./tests/data/b-libav.mkv
 ./tests/data/b-libav.mkv CRC=0x400c29e9
 af195c31e8f49de61e3851ccde4c3ebd *./tests/data/b-pbmpipe.pbm
 317075 ./tests/data/b-pbmpipe.pbm