lavc: switch from ts_end to duration in ff_ass_add_rect.

Make possible a end-to-presentation duration.

1 files changed, 8 insertions, 6 deletions

diff --git a/libavcodec/microdvddec.c b/libavcodec/microdvddec.c
index 083efdb94f..33a75c4f9e 100644
--- a/libavcodec/microdvddec.c
+++ b/libavcodec/microdvddec.c
@@ -261,10 +261,6 @@ static int microdvd_decode_frame(AVCodecContext *avctx,
     char *decoded_sub;
     char *line = avpkt->data;
     char *end = avpkt->data + avpkt->size;
-    int64_t frame_start = avpkt->pts;
-    int64_t frame_end   = avpkt->pts + avpkt->duration;
-    int ts_start = av_rescale_q(frame_start, avctx->time_base, (AVRational){1,100});
-    int ts_end   = av_rescale_q(frame_end,   avctx->time_base, (AVRational){1,100});
     struct microdvd_tag tags[sizeof(MICRODVD_TAGS) - 1] = {{0}};
 
     if (avpkt->size <= 0)
@@ -299,8 +295,14 @@ static int microdvd_decode_frame(AVCodecContext *avctx,
 
 end:
     av_bprint_finalize(&new_line, &decoded_sub);
-    if (*decoded_sub)
-        ff_ass_add_rect(sub, decoded_sub, ts_start, ts_end, 0);
+    if (*decoded_sub) {
+        int64_t start    = avpkt->pts;
+        int64_t duration = avpkt->duration;
+        int ts_start     = av_rescale_q(start,    avctx->time_base, (AVRational){1,100});
+        int ts_duration  = duration != -1 ?
+                           av_rescale_q(duration, avctx->time_base, (AVRational){1,100}) : -1;
+        ff_ass_add_rect(sub, decoded_sub, ts_start, ts_duration, 0);
+    }
     av_free(decoded_sub);
 
     *got_sub_ptr = sub->num_rects > 0;