av1parse: Use the intersected caps to decide the alignment.

When we negotiate with downstream, We should use the intersected
caps of input and output to decide the alignment and stream format.
The current code just uses the input caps which may lack the stream
format.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/1837>

diff --git a/subprojects/gst-plugins-bad/gst/videoparsers/gstav1parse.c b/subprojects/gst-plugins-bad/gst/videoparsers/gstav1parse.c
index ab3af01..c4c6519 100644 (file)
--- a/subprojects/gst-plugins-bad/gst/videoparsers/gstav1parse.c
+++ b/subprojects/gst-plugins-bad/gst/videoparsers/gstav1parse.c
@@ -761,9 +761,11 @@ gst_av1_parse_negotiate (GstAV1Parse * self, GstCaps * in_caps)
   /* Both upsteam and downstream support, best */
   if (in_caps && caps) {
     if (gst_caps_can_intersect (in_caps, caps)) {
-      GST_DEBUG_OBJECT (self, "downstream accepts upstream caps");
-      align = gst_av1_parse_alignment_from_caps (in_caps);
-      gst_clear_caps (&caps);
+      GstCaps *common_caps = NULL;
+
+      common_caps = gst_caps_intersect (in_caps, caps);
+      align = gst_av1_parse_alignment_from_caps (common_caps);
+      gst_clear_caps (&common_caps);
     }
   }
   if (align != GST_AV1_PARSE_ALIGN_NONE)
@@ -867,7 +869,8 @@ gst_av1_parse_set_sink_caps (GstBaseParse * parse, GstCaps * caps)
   if (align == GST_AV1_PARSE_ALIGN_NONE) {
     align = GST_AV1_PARSE_ALIGN_BYTE;
     gst_caps_set_simple (in_caps, "alignment", G_TYPE_STRING,
-        gst_av1_parse_alignment_to_string (align), NULL);
+        gst_av1_parse_alignment_to_string (align),
+        "stream-format", G_TYPE_STRING, "obu-stream", NULL);
   }
 
   /* negotiate with downstream, set output align */