qtdemux: support seeking of CENC encrypted streams

When playing a stream that has been protected by DASH CENC, playback
will fail if a seek is performed. Qtdemux produces the error "stream
is protected using cenc, but no cenc protection system information
has been found" and playback stops.

The problem is that gst_qtdemux_reset() gets called as part of the
FLUSH during a seek. This function frees the protection_system_ids
array. When gst_qtdemux_configure_protected_caps() is called after the
seek has completed, the protection_system_ids array is empty and
qtdemux is unable to create the correct output caps for the protected
stream.

This commit changes it to only free the protection_system_ids on
hard resets.

https://bugzilla.gnome.org/show_bug.cgi?id=761787

diff --git a/gst/isomp4/qtdemux.c b/gst/isomp4/qtdemux.c
index c4aa9c5..e3e2d9d 100644 (file)
--- a/gst/isomp4/qtdemux.c
+++ b/gst/isomp4/qtdemux.c
@@ -1973,10 +1973,6 @@ gst_qtdemux_reset (GstQTDemux * qtdemux, gboolean hard)
     qtdemux->have_group_id = FALSE;
     qtdemux->group_id = G_MAXUINT;
 
-    if (qtdemux->protection_system_ids) {
-      g_ptr_array_free (qtdemux->protection_system_ids, TRUE);
-      qtdemux->protection_system_ids = NULL;
-    }
     g_queue_foreach (&qtdemux->protection_event_queue, (GFunc) gst_event_unref,
         NULL);
     g_queue_clear (&qtdemux->protection_event_queue);
@@ -2001,6 +1997,10 @@ gst_qtdemux_reset (GstQTDemux * qtdemux, gboolean hard)
     qtdemux->timescale = 0;
     qtdemux->got_moov = FALSE;
     qtdemux->pending_configure = FALSE;
+    if (qtdemux->protection_system_ids) {
+      g_ptr_array_free (qtdemux->protection_system_ids, TRUE);
+      qtdemux->protection_system_ids = NULL;
+    }
   } else if (qtdemux->mss_mode) {
     gst_flow_combiner_reset (qtdemux->flowcombiner);
     for (n = 0; n < qtdemux->n_streams; n++)