surfaceproxy: add copy function.

Add gst_vaapi_surface_proxy_copy() function that creates a new surface
proxy with the same information from the parent proxy, except that the
user-defined destroy notify function is not copied over.

The underlying VA surface is pushed back to the video pool only when
the last reference to the parent surface proxy is released.

docs/reference/libs/libs-sections.txt

@@ -366,6 +366,7 @@ gst_vaapi_surface_proxy_get_surface
 gst_vaapi_surface_proxy_get_surface_id
 gst_vaapi_surface_proxy_get_timestamp
 gst_vaapi_surface_proxy_new_from_pool
+gst_vaapi_surface_proxy_copy
 gst_vaapi_surface_proxy_ref
 gst_vaapi_surface_proxy_replace
 gst_vaapi_surface_proxy_set_destroy_notify

gst-libs/gst/vaapi/gstvaapisurfaceproxy.c

@@ -39,12 +39,13 @@ static void
 gst_vaapi_surface_proxy_finalize(GstVaapiSurfaceProxy *proxy)
 {
     if (proxy->surface) {
-        if (proxy->pool)
+        if (proxy->pool && !proxy->parent)
             gst_vaapi_video_pool_put_object(proxy->pool, proxy->surface);
         gst_vaapi_object_unref(proxy->surface);
         proxy->surface = NULL;
     }
     gst_vaapi_video_pool_replace(&proxy->pool, NULL);
+    gst_vaapi_surface_proxy_replace(&proxy->parent, NULL);
 
     /* Notify the user function that the object is now destroyed */
     if (proxy->destroy_func)
@@ -61,6 +62,17 @@ gst_vaapi_surface_proxy_class(void)
     return &GstVaapiSurfaceProxyClass;
 }
 
+/**
+ * gst_vaapi_surface_proxy_new_from_pool:
+ * @pool: a #GstVaapiSurfacePool
+ *
+ * Allocates a new surface from the supplied surface @pool and creates
+ * the wrapped surface proxy object from it. When the last reference
+ * to the proxy object is released, then the underlying VA surface is
+ * pushed back to its parent pool.
+ *
+ * Returns: The same newly allocated @proxy object, or %NULL on error
+ */
 GstVaapiSurfaceProxy *
 gst_vaapi_surface_proxy_new_from_pool(GstVaapiSurfacePool *pool)
 {
@@ -73,6 +85,7 @@ gst_vaapi_surface_proxy_new_from_pool(GstVaapiSurfacePool *pool)
     if (!proxy)
         return NULL;
 
+    proxy->parent = NULL;
     proxy->destroy_func = NULL;
     proxy->pool = gst_vaapi_video_pool_ref(pool);
     proxy->surface = gst_vaapi_video_pool_get_object(proxy->pool);
@@ -89,6 +102,48 @@ error:
     return NULL;
 }
 
+
+/**
+ * gst_vaapi_surface_proxy_copy:
+ * @proxy: the parent #GstVaapiSurfaceProxy
+ *
+ * Creates are new VA surface proxy object from the supplied parent
+ * @proxy object with the same initial information, e.g. timestamp,
+ * duration.
+ *
+ * Note: the destroy notify function is not copied into the new
+ * surface proxy object.
+ *
+ * Returns: The same newly allocated @proxy object, or %NULL on error
+ */
+GstVaapiSurfaceProxy *
+gst_vaapi_surface_proxy_copy(GstVaapiSurfaceProxy *proxy)
+{
+    GstVaapiSurfaceProxy *copy;
+
+    g_return_val_if_fail(proxy != NULL, NULL);
+
+    copy = (GstVaapiSurfaceProxy *)
+        gst_vaapi_mini_object_new(gst_vaapi_surface_proxy_class());
+    if (!copy)
+        return NULL;
+
+    GST_VAAPI_SURFACE_PROXY_FLAGS(copy) =
+        GST_VAAPI_SURFACE_PROXY_FLAGS(proxy);
+
+    copy->parent = gst_vaapi_surface_proxy_ref(proxy->parent ?
+        proxy->parent : proxy);
+    copy->pool = gst_vaapi_video_pool_ref(proxy->pool);
+    copy->surface = gst_vaapi_object_ref(proxy->surface);
+    copy->timestamp = proxy->timestamp;
+    copy->duration = proxy->duration;
+    copy->destroy_func = NULL;
+    copy->has_crop_rect = proxy->has_crop_rect;
+    if (copy->has_crop_rect)
+        copy->crop_rect = proxy->crop_rect;
+    return copy;
+}
+
 /**
  * gst_vaapi_surface_proxy_ref:
  * @proxy: a #GstVaapiSurfaceProxy

gst-libs/gst/vaapi/gstvaapisurfaceproxy.h

@@ -90,6 +90,9 @@ typedef enum {
 GstVaapiSurfaceProxy *
 gst_vaapi_surface_proxy_new_from_pool(GstVaapiSurfacePool *pool);
 
+GstVaapiSurfaceProxy *
+gst_vaapi_surface_proxy_copy(GstVaapiSurfaceProxy *proxy);
+
 GstVaapiSurfaceProxy *
 gst_vaapi_surface_proxy_ref(GstVaapiSurfaceProxy *proxy);
 

gst-libs/gst/vaapi/gstvaapisurfaceproxy_priv.h

@@ -36,6 +36,7 @@
 struct _GstVaapiSurfaceProxy {
     /*< private >*/
     GstVaapiMiniObject  parent_instance;
+    GstVaapiSurfaceProxy *parent;
 
     GstVaapiVideoPool  *pool;
     GstVaapiSurface    *surface;