basetsmux: fix SCTE pts_adjustment with offsets

When there are elements between the demuxer and the muxer that
introduce an offset to the running time, or when offsets are
set on pads by the application, this shift must be taken into
account when calculating the final pts_adjustement.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/913>

diff --git a/subprojects/gst-plugins-bad/gst/mpegtsmux/gstbasetsmux.c b/subprojects/gst-plugins-bad/gst/mpegtsmux/gstbasetsmux.c
index d60afb0..fc78be5 100644 (file)
--- a/subprojects/gst-plugins-bad/gst/mpegtsmux/gstbasetsmux.c
+++ b/subprojects/gst-plugins-bad/gst/mpegtsmux/gstbasetsmux.c
@@ -1550,8 +1550,9 @@ deep_copy_sit (const GstMpegtsSCTESIT * sit)
  * to the application to ensure that that is the case.
  */
 static void
-handle_scte35_section (GstBaseTsMux * mux, GstMpegtsSection * section,
-    guint64 mpeg_pts_offset, GstStructure * rtime_map)
+handle_scte35_section (GstBaseTsMux * mux, GstEvent * event,
+    GstMpegtsSection * section, guint64 mpeg_pts_offset,
+    GstStructure * rtime_map)
 {
   GstMpegtsSCTESIT *sit;
   guint i;
@@ -1744,6 +1745,11 @@ handle_scte35_section (GstBaseTsMux * mux, GstMpegtsSection * section,
      * - Our own 1-hour offset
      */
     pts_adjust = sit->pts_adjustment + mpeg_pts_offset + TS_MUX_CLOCK_BASE;
+
+    /* Account for offsets potentially introduced between the demuxer and us */
+    pts_adjust +=
+        GSTTIME_TO_MPEGTIME (gst_event_get_running_time_offset (event));
+
     pts_adjust &= 0x1ffffffff;
     section_data = g_memdup (section->data, section->section_length);
     section_data[4] |= pts_adjust >> 32;
@@ -1790,7 +1796,7 @@ gst_base_ts_mux_send_event (GstElement * element, GstEvent * event)
     GST_DEBUG ("Received event with mpegts section");
 
     if (section->section_type == GST_MPEGTS_SECTION_SCTE_SIT) {
-      handle_scte35_section (mux, section, 0, NULL);
+      handle_scte35_section (mux, event, section, 0, NULL);
     } else {
       /* TODO: Check that the section type is supported */
       tsmux_add_mpegts_si_section (mux->tsmux, section);
@@ -1847,7 +1853,8 @@ gst_base_ts_mux_sink_event (GstAggregator * agg, GstAggregatorPad * agg_pad,
                 &rtime_map, NULL);
             gst_structure_get_uint64 (s, "mpeg-pts-offset", &mpeg_pts_offset);
 
-            handle_scte35_section (mux, section, mpeg_pts_offset, rtime_map);
+            handle_scte35_section (mux, event, section, mpeg_pts_offset,
+                rtime_map);
             if (rtime_map)
               gst_structure_free (rtime_map);
             mux->last_scte35_event_seqnum = gst_event_get_seqnum (event);