define getter for FilterContext.graph

av/filter/context.pxd

@@ -7,7 +7,7 @@ from av.filter.graph cimport Graph
 cdef class FilterContext:
 
     cdef lib.AVFilterContext *ptr
-    cdef readonly object graph
+    cdef readonly object _graph
     cdef readonly Filter filter
 
     cdef object _inputs

av/filter/context.pyi

@@ -1,4 +1,5 @@
 from av.frame import Frame
+from av.filter import Graph
 
 from .pad import FilterContextPad
 
@@ -13,3 +14,4 @@ class FilterContext:
     ) -> None: ...
     def push(self, frame: Frame) -> None: ...
     def pull(self) -> Frame: ...
+    def graph(self) -> Graph: ...

av/filter/context.pyx

@@ -15,7 +15,7 @@ cdef object _cinit_sentinel = object()
 
 cdef FilterContext wrap_filter_context(Graph graph, Filter filter, lib.AVFilterContext *ptr):
     cdef FilterContext self = FilterContext(_cinit_sentinel)
-    self.graph = weakref.ref(graph)
+    self._graph = weakref.ref(graph)
     self.filter = filter
     self.ptr = ptr
     return self
@@ -74,6 +74,13 @@ cdef class FilterContext:
 
     def link_to(self, FilterContext input_, int output_idx=0, int input_idx=0):
         err_check(lib.avfilter_link(self.ptr, output_idx, input_.ptr, input_idx))
+
+    @property
+    def graph(self):
+        if (gr := self._graph()):
+            return gr
+        else:
+            raise RuntimeError("graph is unallocated")
 
     def push(self, Frame frame):
         cdef int res
@@ -116,10 +123,7 @@ cdef class FilterContext:
                 raise ValueError("cannot delegate pull without linked output")
             return self.outputs[0].linked.context.pull()
 
-        if (gr := self.graph()):
-            gr.configure()
-        else:
-            raise RuntimeError("graph is dead")
+        self.graph.configure()
 
         with nogil:
             res = lib.av_buffersink_get_frame(self.ptr, frame.ptr)