ffmpeg_opt: Respect default disposition when select audio/video

Respect default disposition when select audio/video
Reviewed-by: NMichael Niedermayer <michael@niedermayer.cc>
Signed-off-by: NJun Zhao <barryjzhao@tencent.com>

fftools/ffmpeg_opt.c

@@ -2198,7 +2198,8 @@ static int open_output_file(OptionsContext *o, const char *filename)
             for (i = 0; i < nb_input_streams; i++) {
                 int new_area;
                 ist = input_streams[i];
-                new_area = ist->st->codecpar->width * ist->st->codecpar->height + 100000000*!!ist->st->codec_info_nb_frames;
+                new_area = ist->st->codecpar->width * ist->st->codecpar->height + 100000000*!!ist->st->codec_info_nb_frames
+                           + 5000000*!!(ist->st->disposition & AV_DISPOSITION_DEFAULT);
                 if (ist->user_set_discard == AVDISCARD_ALL)
                     continue;
                 if((qcr!=MKTAG('A', 'P', 'I', 'C')) && (ist->st->disposition & AV_DISPOSITION_ATTACHED_PIC))
@@ -2221,7 +2222,8 @@ static int open_output_file(OptionsContext *o, const char *filename)
             for (i = 0; i < nb_input_streams; i++) {
                 int score;
                 ist = input_streams[i];
-                score = ist->st->codecpar->channels + 100000000*!!ist->st->codec_info_nb_frames;
+                score = ist->st->codecpar->channels + 100000000*!!ist->st->codec_info_nb_frames
+                        + 5000000*!!(ist->st->disposition & AV_DISPOSITION_DEFAULT);
                 if (ist->user_set_discard == AVDISCARD_ALL)
                     continue;
                 if (ist->st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO &&