From 2d74b2d832659efc81090a2c6bd9808ffeba3bc2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jan=20Ekstr=C3=B6m?= <jeebjp@gmail.com>
Date: Wed, 18 Sep 2019 21:29:25 +0300
Subject: [PATCH] sub/sd_ass: utilize UINT32_MAX subtitle duration for unknown

US closed captions, teletext and ARIB caption decoders utilize this
value.
---
 sub/lavc_conv.c |  8 +++++---
 sub/sd_ass.c    | 15 ++++++++-------
 2 files changed, 13 insertions(+), 10 deletions(-)

diff --git a/sub/lavc_conv.c b/sub/lavc_conv.c
index 7077116180..65ebc0d8c7 100644
--- a/sub/lavc_conv.c
+++ b/sub/lavc_conv.c
@@ -260,9 +260,11 @@ char **lavc_conv_decode(struct lavc_conv *priv, struct demux_packet *packet,
     } else if (got_sub) {
         *sub_pts = packet->pts + mp_pts_from_av(priv->cur.start_display_time,
                                                &avctx->time_base);
-        *sub_duration = mp_pts_from_av(priv->cur.end_display_time -
-                                      priv->cur.start_display_time,
-                                      &avctx->time_base);
+        *sub_duration = priv->cur.end_display_time == UINT32_MAX ?
+                        UINT32_MAX :
+                        mp_pts_from_av(priv->cur.end_display_time -
+                                       priv->cur.start_display_time,
+                                       &avctx->time_base);
 
         for (int i = 0; i < priv->cur.num_rects; i++) {
             if (priv->cur.rects[i]->w > 0 && priv->cur.rects[i]->h > 0)
diff --git a/sub/sd_ass.c b/sub/sd_ass.c
index d3eee38a45..bf2a49eb9e 100644
--- a/sub/sd_ass.c
+++ b/sub/sd_ass.c
@@ -234,17 +234,18 @@ static void decode(struct sd *sd, struct demux_packet *packet)
         if (!sd->opts->sub_clear_on_seek && packet->pos >= 0 &&
             check_packet_seen(sd, packet->pos))
             return;
-        if (packet->duration < 0) {
-            if (!ctx->duration_unknown) {
-                MP_WARN(sd, "Subtitle with unknown duration.\n");
-                ctx->duration_unknown = true;
-            }
-            packet->duration = UNKNOWN_DURATION;
-        }
+
         double sub_pts = 0;
         double sub_duration = 0;
         char **r = lavc_conv_decode(ctx->converter, packet, &sub_pts,
                                     &sub_duration);
+        if (packet->duration < 0 || sub_duration == UINT32_MAX) {
+            if (!ctx->duration_unknown) {
+                MP_WARN(sd, "Subtitle with unknown duration.\n");
+                ctx->duration_unknown = true;
+            }
+            sub_duration = UNKNOWN_DURATION;
+        }
 
         for (int n = 0; r && r[n]; n++) {
             char *ass_line = r[n];