dvbsub: fix encoding of termination packets.

The old code generates a termination packet with the same regions as the
start packet and page_state set to "only what changed"; the result is
that the termination packet is decoded as identical to the start packet.

The new code does as found in some DVB broadcasts: produce a packet with
no regions. This is done by expecting num_rects to be 0 rather than
using a flip-flop. ffmpeg.c is updated accordingly.

1 files changed, 2 insertions, 0 deletions

diff --git a/ffmpeg.c b/ffmpeg.c
index ea90ada0ae..b2963bbad0 100644
--- a/ffmpeg.c
+++ b/ffmpeg.c
@@ -703,6 +703,8 @@ static void do_subtitle_out(AVFormatContext *s,
         sub->pts               += av_rescale_q(sub->start_display_time, (AVRational){ 1, 1000 }, AV_TIME_BASE_Q);
         sub->end_display_time  -= sub->start_display_time;
         sub->start_display_time = 0;
+        if (i == 1)
+            sub->num_rects = 0;
         subtitle_out_size = avcodec_encode_subtitle(enc, subtitle_out,
                                                     subtitle_out_max_size, sub);
         if (subtitle_out_size < 0) {