avcodec/dvbsubdec: make compute_edt user settable

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

ffmpeg.c

@@ -2298,7 +2298,7 @@ static int init_input_stream(int ist_index, char *error, int error_len)
 
         av_opt_set_int(ist->dec_ctx, "refcounted_frames", 1, 0);
         if(ist->dec_ctx->codec_id == AV_CODEC_ID_DVB_SUBTITLE)
-            av_dict_set(&ist->decoder_opts, "compute_edt", "1", 0);
+            av_dict_set(&ist->decoder_opts, "compute_edt", "1", AV_DICT_DONT_OVERWRITE);
 
         if (!av_dict_get(ist->decoder_opts, "threads", NULL, 0))
             av_dict_set(&ist->decoder_opts, "threads", "auto", 0);

libavcodec/dvbsubdec.c

@@ -1585,8 +1585,9 @@ end:
     return p - buf;
 }
 
+#define DS AV_OPT_FLAG_DECODING_PARAM | AV_OPT_FLAG_SUBTITLE_PARAM
 static const AVOption options[] = {
-    {"compute_edt", "compute end of time using pts or timeout", offsetof(DVBSubContext, compute_edt), FF_OPT_TYPE_INT, {.i64 = 0}, 0, 1, 0},
+    {"compute_edt", "compute end of time using pts or timeout", offsetof(DVBSubContext, compute_edt), FF_OPT_TYPE_INT, {.i64 = 0}, 0, 1, DS},
     {NULL}
 };
 static const AVClass dvbsubdec_class = {