basetransform: add recursive-accept-caps handlerrecursive-accept-caps

The handler will do an accept-caps to check if the caps is accepted
by the element and, if successful, create new query with the output
caps and send it to its peer.

1 files changed, 50 insertions, 0 deletions

diff --git a/libs/gst/base/gstbasetransform.c b/libs/gst/base/gstbasetransform.c
index 4155a51a6..a9122270e 100644
--- a/libs/gst/base/gstbasetransform.c
+++ b/libs/gst/base/gstbasetransform.c
@@ -1590,6 +1590,56 @@ gst_base_transform_default_query (GstBaseTransform * trans,
       }
       break;
     }
+    case GST_QUERY_RECURSIVE_ACCEPT_CAPS:
+    {
+      GstCaps *caps;
+      GstQuery *accept_caps_query;
+      gboolean accept_caps_result;
+
+      gst_query_parse_recursive_accept_caps (query, &caps);
+
+      /* check if we accept it */
+      accept_caps_query = gst_query_new_accept_caps (gst_caps_ref (caps));
+      if (!gst_pad_query (pad, query)) {
+        GST_DEBUG_OBJECT (pad, "Accept-caps query got no answer, can't "
+            "proceed with recursive-accept-caps");
+        break;
+      }
+
+      gst_query_parse_accept_caps_result (accept_caps_query,
+          &accept_caps_result);
+      gst_query_unref (accept_caps_query);
+      if (accept_caps_result) {
+        GstCaps *othercaps;
+        GstQuery *peer_query;
+        gboolean peer_query_result;
+
+        /* convert our caps to the output caps and proceed with the query */
+        othercaps = gst_base_transform_find_transform (trans, pad, caps);
+        if (!othercaps || gst_caps_is_empty (othercaps)) {
+          GST_DEBUG_OBJECT (pad, "Could not generate othercaps from caps %"
+              GST_PTR_FORMAT, caps);
+          gst_query_set_recursive_accept_caps_result (query, FALSE);
+          gst_caps_unref (othercaps);
+          ret = TRUE;
+        } else {
+          peer_query = gst_query_new_recursive_accept_caps (othercaps);
+          if (gst_pad_peer_query (otherpad, peer_query)) {
+            ret = TRUE;
+            gst_query_parse_recursive_accept_caps_result (peer_query,
+                &peer_query_result);
+            gst_query_set_recursive_accept_caps_result (query,
+                peer_query_result);
+          }
+          gst_query_unref (peer_query);
+        }
+
+      } else {
+        ret = TRUE;
+        gst_query_set_recursive_accept_caps_result (query, FALSE);
+      }
+      break;
+    }
     case GST_QUERY_CAPS:
     {
       GstCaps *filter, *caps;