diff --git a/av/frame.pyx b/av/frame.pyx
index b98624cc5..352b68157 100644
--- a/av/frame.pyx
+++ b/av/frame.pyx
@@ -75,6 +75,12 @@ cdef class Frame:
                 return None
             return self.ptr.pkt_dts
 
+        def __set__(self, value):
+            if value is None:
+                self.ptr.pkt_dts = lib.AV_NOPTS_VALUE
+            else:
+                self.ptr.pkt_dts = value
+
     property pts:
         """
         The presentation timestamp in :attr:`time_base` units for this frame.
diff --git a/av/packet.pyx b/av/packet.pyx
index 0687b2237..af77e2c10 100644
--- a/av/packet.pyx
+++ b/av/packet.pyx
@@ -196,5 +196,17 @@ cdef class Packet(Buffer):
     property is_keyframe:
         def __get__(self): return bool(self.ptr.flags & lib.AV_PKT_FLAG_KEY)
 
+        def __set__(self, v):
+            if v:
+                self.ptr.flags |= lib.AV_PKT_FLAG_KEY
+            else:
+                self.ptr.flags &= ~(lib.AV_PKT_FLAG_KEY)
+
     property is_corrupt:
         def __get__(self): return bool(self.ptr.flags & lib.AV_PKT_FLAG_CORRUPT)
+
+        def __set__(self, v):
+            if v:
+                self.ptr.flags |= lib.AV_PKT_FLAG_CORRUPT
+            else:
+                self.ptr.flags &= ~(lib.AV_PKT_FLAG_CORRUPT)