Expose CodecContext flush_buffers

av/codec/context.pxd

@@ -37,6 +37,8 @@ cdef class CodecContext:
     cpdef encode(self, Frame frame=?)
     cpdef decode(self, Packet packet=?)
 
+    cpdef flush_buffers(self)
+
     # Used by both transcode APIs to setup user-land objects.
     # TODO: Remove the `Packet` from `_setup_decoded_frame` (because flushing
     # packets are bogus). It should take all info it needs from the context and/or stream.

av/codec/context.pyi

@@ -1,6 +1,7 @@
 from typing import Any, Literal
 
 from av.enum import EnumFlag, EnumItem
+from av.frame import Frame
 from av.packet import Packet
 
 from .codec import Codec
@@ -78,3 +79,6 @@ class CodecContext:
     def parse(
         self, raw_input: bytes | bytearray | memoryview | None = None
     ) -> list[Packet]: ...
+    def encode(self, frame: Frame | None) -> list[Packet]: ...
+    def decode(self, packet: Packet | None) -> list[Frame]: ...
+    def flush_buffers(self) -> None: ...

av/codec/context.pyx

@@ -510,6 +510,17 @@ cdef class CodecContext:
             res.append(frame)
         return res
 
+    cpdef flush_buffers(self):
+        """Reset the internal codec state and discard all internal buffers.
+
+        Should be called before you start decoding from a new position e.g.
+        when seeking or when switching to a different stream.
+
+        """
+        if self.is_open:
+            with nogil:
+                lib.avcodec_flush_buffers(self.ptr)
+
     cdef _setup_decoded_frame(self, Frame frame, Packet packet):
 
         # Propagate our manual times.

av/container/input.pyx

@@ -278,6 +278,5 @@ cdef class InputContainer(Container):
 
         for stream in self.streams:
             codec_context = stream.codec_context
-            if codec_context and codec_context.is_open:
-                with nogil:
-                    lib.avcodec_flush_buffers(codec_context.ptr)
+            if codec_context:
+                codec_context.flush_buffers()