ffmpeg: allow overriding and amending AVStream->disposition

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

ffmpeg.c

@@ -2968,6 +2968,37 @@ static int transcode_init(void)
                 }
             }
         }
+
+        if (ost->disposition) {
+            static const AVOption opts[] = {
+                { "disposition"         , NULL, 0, AV_OPT_TYPE_FLAGS, { .i64 = 0 }, INT64_MIN, INT64_MAX, .unit = "flags" },
+                { "default"             , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_DISPOSITION_DEFAULT           },    .unit = "flags" },
+                { "dub"                 , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_DISPOSITION_DUB               },    .unit = "flags" },
+                { "original"            , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_DISPOSITION_ORIGINAL          },    .unit = "flags" },
+                { "comment"             , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_DISPOSITION_COMMENT           },    .unit = "flags" },
+                { "lyrics"              , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_DISPOSITION_LYRICS            },    .unit = "flags" },
+                { "karaoke"             , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_DISPOSITION_KARAOKE           },    .unit = "flags" },
+                { "forced"              , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_DISPOSITION_FORCED            },    .unit = "flags" },
+                { "hearing_impaired"    , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_DISPOSITION_HEARING_IMPAIRED  },    .unit = "flags" },
+                { "visual_impaired"     , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_DISPOSITION_VISUAL_IMPAIRED   },    .unit = "flags" },
+                { "clean_effects"       , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_DISPOSITION_CLEAN_EFFECTS     },    .unit = "flags" },
+                { "captions"            , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_DISPOSITION_CAPTIONS          },    .unit = "flags" },
+                { "descriptions"        , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_DISPOSITION_DESCRIPTIONS      },    .unit = "flags" },
+                { "metadata"            , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_DISPOSITION_METADATA          },    .unit = "flags" },
+                { NULL },
+            };
+            static const AVClass class = {
+                .class_name = "",
+                .item_name  = av_default_item_name,
+                .option     = opts,
+                .version    = LIBAVUTIL_VERSION_INT,
+            };
+            const AVClass *pclass = &class;
+
+            ret = av_opt_eval_flags(&pclass, &opts[0], ost->disposition, &ost->st->disposition);
+            if (ret < 0)
+                goto dump_format;
+        }
     }
 
     /* open each encoder */
@@ -3879,6 +3910,7 @@ static int transcode(void)
                 }
                 av_freep(&ost->forced_kf_pts);
                 av_freep(&ost->apad);
+                av_freep(&ost->disposition);
                 av_dict_free(&ost->encoder_opts);
                 av_dict_free(&ost->swr_opts);
                 av_dict_free(&ost->resample_opts);

ffmpeg.h

@@ -206,6 +206,8 @@ typedef struct OptionsContext {
     int        nb_apad;
     SpecifierOpt *discard;
     int        nb_discard;
+    SpecifierOpt *disposition;
+    int        nb_disposition;
 } OptionsContext;
 
 typedef struct InputFilter {
@@ -430,6 +432,7 @@ typedef struct OutputStream {
     const char *attachment_filename;
     int copy_initial_nonkeyframes;
     int copy_prior_start;
+    char *disposition;
 
     int keep_pix_fmt;
 

ffmpeg_opt.c

@@ -1186,6 +1186,9 @@ static OutputStream *new_output_stream(OptionsContext *o, AVFormatContext *oc, e
         ost->enc_ctx->global_quality = FF_QP2LAMBDA * qscale;
     }
 
+    MATCH_PER_STREAM_OPT(disposition, str, ost->disposition, oc, st);
+    ost->disposition = av_strdup(ost->disposition);
+
     if (oc->oformat->flags & AVFMT_GLOBALHEADER)
         ost->enc_ctx->flags |= CODEC_FLAG_GLOBAL_HEADER;
 
@@ -2937,6 +2940,9 @@ const OptionDef options[] = {
     { "discard",        OPT_STRING | HAS_ARG | OPT_SPEC |
                         OPT_INPUT,                                   { .off = OFFSET(discard) },
         "discard", "" },
+    { "disposition",    OPT_STRING | HAS_ARG | OPT_SPEC |
+                        OPT_OUTPUT,                                  { .off = OFFSET(disposition) },
+        "disposition", "" },
 
     /* video options */
     { "vframes",      OPT_VIDEO | HAS_ARG  | OPT_PERFILE | OPT_OUTPUT,           { .func_arg = opt_video_frames },