From 1c4f9fafaa17df4e1eddea06329f34537af1ef50 Mon Sep 17 00:00:00 2001
From: Damiano Galassi <damiog@gmail.com>
Date: Sat, 16 Jul 2022 10:02:27 +0200
Subject: [PATCH 2/2] dvdsubdec: use pts of initial packet

When the source is DVD, only the initial packet of a subtitle that spans
multiple packets will have a pts value. Original patch by John Stebbins.
---
 libavcodec/dvdsubdec.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/libavcodec/dvdsubdec.c b/libavcodec/dvdsubdec.c
index fdeead372b..13e7ccad9d 100644
--- a/libavcodec/dvdsubdec.c
+++ b/libavcodec/dvdsubdec.c
@@ -43,6 +43,7 @@ typedef struct DVDSubContext
   int      buf_size;
   int      forced_subs_only;
   uint8_t  used_color[256];
+  int64_t  pts;
 } DVDSubContext;
 
 static void yuv_a_to_rgba(const uint8_t *ycbcr, const uint8_t *alpha, uint32_t *rgba, int num_values)
@@ -522,10 +523,13 @@ static int dvdsub_decode(AVCodecContext *avctx, AVSubtitle *sub,
     int appended = 0;
     int is_menu;
 
+    if (ctx->pts == AV_NOPTS_VALUE && sub->pts != AV_NOPTS_VALUE)
+        ctx->pts = sub->pts;
     if (ctx->buf_size) {
         int ret = append_to_cached_buf(avctx, buf, buf_size);
         if (ret < 0) {
             *data_size = 0;
+            ctx->pts = AV_NOPTS_VALUE;
             return ret;
         }
         buf = ctx->buf;
@@ -538,6 +542,7 @@ static int dvdsub_decode(AVCodecContext *avctx, AVSubtitle *sub,
         *data_size = 0;
         int ret = appended ? 0 : append_to_cached_buf(avctx, buf, buf_size);
         if (ret < 0) {
+            ctx->pts = AV_NOPTS_VALUE;
             return ret;
         }
         return buf_size;
@@ -549,6 +554,7 @@ static int dvdsub_decode(AVCodecContext *avctx, AVSubtitle *sub,
         reset_rects(sub);
         *data_size = 0;
 
+        ctx->pts = AV_NOPTS_VALUE;
         return buf_size;
     }
     if (!is_menu && find_smallest_bounding_rectangle(ctx, sub) == 0)
@@ -559,6 +565,8 @@ static int dvdsub_decode(AVCodecContext *avctx, AVSubtitle *sub,
 
     ctx->buf_size = 0;
     *data_size = 1;
+    sub->pts = ctx->pts;
+    ctx->pts = AV_NOPTS_VALUE;
     return buf_size;
 }
 
@@ -684,6 +692,7 @@ static av_cold int dvdsub_init(AVCodecContext *avctx)
             av_log(avctx, AV_LOG_DEBUG, " 0x%06"PRIx32, ctx->palette[i]);
         av_log(avctx, AV_LOG_DEBUG, "\n");
     }
+    ctx->pts = AV_NOPTS_VALUE;
 
     return 1;
 }
-- 
2.32.1 (Apple Git-133)