PyAV-Org · WyattBlue · Aug 13, 2026 · Aug 13, 2026
diff --git a/CHANGELOG.rst b/CHANGELOG.rst
@@ -28,191 +28,17 @@ We are operating with `semantic versioning <https://semver.org>`_.
     - Bug fixes (PATCH) go here. 
     - $CHANGE by :gh-user:`mikeboers` in (:pr:`1`).
 
-v18.1.0
--------
-
-Features:
-
-- Infer the specific stream and codec context types for all FFmpeg encoder names in type-checked code by :gh-user:`WyattBlue`.
-- Add ``CodecContext.supported_options`` to discover generic and codec-specific options by :gh-user:`WyattBlue` (:issue:`2032`).
-- Add ``Packet.rescale_ts()`` to rescale packet PTS, DTS, and duration to a new ``AVRational`` time base by :gh-user:`WyattBlue`.
-- Support reusing the thread's current CUDA context via a ``current_ctx`` flag on ``CudaContext`` and ``VideoFrame.from_dlpack``, for interop with libraries like PyTorch that initialize CUDA first by :gh-user:`Yozer` (:pr:`2339`).
-- ``VideoFrame.from_dlpack`` no longer requires restating ``primary_ctx``/``current_ctx`` when passing an explicit ``cuda_context``; the flags are only validated when explicitly given by :gh-user:`WyattBlue`.
-- Support passing an explicit CUDA stream to FFmpeg CUDA operations, including NVENC input and output, via a ``cuda_stream`` parameter on ``CudaContext``; currently limited to logical CUDA device 0 by :gh-user:`Yozer` (:pr:`2360`).
-- Add ``av.AVRational``, an exact rational number stored as two int32s that mirrors FFmpeg's ``AVRational``. ``Codec.frame_rates`` now holds these rather than ``fractions.Fraction``, and every setter that accepts a ``Fraction`` also accepts an ``AVRational``. Unset rational attributes are falsy, so test them with ``if not stream.time_base:`` rather than ``is None`` by :gh-user:`WyattBlue`.
-- Add ``Frame.metadata``, the metadata FFmpeg attaches to a frame, by :gh-user:`WyattBlue`.
-- Add ``CodecContext.level`` by :gh-user:`WyattBlue`.
-- Add ``VideoCodecContext.field_order`` by :gh-user:`WyattBlue`.
-- ``VideoFrame.save`` now forwards keyword arguments to the encoder, letting callers trade file size for speed (e.g. ``pred="none"`` or ``compression_level=1`` for PNG, ``qscale=2`` for JPG) by :gh-user:`WyattBlue`.
-- Add ``InputContainer.start_time_realtime``, the stream's start time in microseconds since the Unix epoch, which RTSP derives from RTCP sender reports, by :gh-user:`WyattBlue` (:issue:`2365`).
+v19.0.0 (Unreleased)
+--------------------
 
 Fixes:
 
-- Fix ``VideoFrame.save`` raising ``AttributeError`` when given a ``Path`` rather than a ``str`` by :gh-user:`WyattBlue`.
-- Fix a frame rate assigned to a ``VideoStream`` after ``add_stream`` being dropped from the output; the codec context's frame rate is now copied to the stream before the header is written by :gh-user:`WyattBlue` (:issue:`2301`).
+- 
 
-Misc.:
 
-- Support building from source against FFmpeg 9.0 by :gh-user:`WyattBlue`. The binary wheels still ship FFmpeg 8.1.2.
-
-- Prevent crashes and corrupted output when structural codec properties are changed after an output stream has been opened by :gh-user:`WyattBlue`, reported by :gh-user:`oakaigh` (:issue:`2232`).
-- Fix a crash when using a stream that has no ``CodecContext`` (a demuxed stream with no available decoder, such as one from a truncated file, or a stream created by ``add_mux_stream``); decoding now raises ``DecoderNotFoundError``, encoding now raises ``EncoderNotFoundError``, and ``BitStreamFilterContext`` accepts such a stream as ``out_stream`` by :gh-user:`WyattBlue`, reported by :gh-user:`justinrmiller` (:issue:`2344`).
-
-v18.0.0
--------
-
-Breaking:
-
-- Remove Python 3.10
-
-Features:
-
-- Support HW encoding via a ``hwaccel`` parameter on ``OutputContainer.add_stream`` (e.g. ``h264_vaapi``, ``h264_nvenc``, ``h264_videotoolbox``); software frames passed to ``encode`` are uploaded to the device automatically by :gh-user:`WyattBlue` (:issue:`2156`).
-- Use FFmpeg 8.1.2 in the binary wheels by :gh-user:`WyattBlue`.
-- Expose ``sw_format`` on ``VideoCodecContext``, and allow configuring the software format of hardware encoders by :gh-user:`WyattBlue`.
-- Add ``options`` parameter to ``AudioResampler`` for passing ``libswresample`` options (e.g. ``resampler``, ``filter_size``, ``cutoff``) by :gh-user:`WyattBlue` (:issue:`2262`).
-- Support ``yuv420p10le`` in ``VideoFrame.to_ndarray`` and ``VideoFrame.from_ndarray`` by :gh-user:`WyattBlue` (:issue:`1981`).
-- Add ``at`` parameter to ``Graph.push`` and ``Graph.vpush`` to push a frame to a single buffer source by index, for multi-input filters like ``overlay`` by :gh-user:`WyattBlue`.
-- ``find_best_pix_fmt_of_list`` now returns the loss as a ``PixFmtLoss`` ``enum.IntFlag`` instead of a plain ``int`` by :gh-user:`WyattBlue` (:issue:`2300`).
-- Add ``Colorspace.BT2020`` by :gh-user:`mark-oshea`.
-- ``BitStreamFilterContext`` now accepts a ``Codec`` or a codec-name ``str`` as ``in_stream`` to pin the input codec without a full ``Stream`` by :gh-user:`WyattBlue`.
-
-Fixes:
-
-- Fix ``VideoFrame.reformat`` (and ``to_ndarray``/``to_rgb``/``to_image``) raising ``OSError`` ``Operation not supported`` on frames tagged with reserved or otherwise unsupported ``color_primaries``/``color_trc`` values (e.g. VP9 and NVDEC output); a transfer/primaries conversion is now only performed when explicitly requested by :gh-user:`WyattBlue` (:issue:`2208`).
-- Fix ``add_mux_stream`` producing unwritable Matroska files by extracting codec extradata from the bitstream before the header is written by :gh-user:`WyattBlue` (:issue:`2198`).
-- Encode GPU frames (e.g. CUDA frames from DLPack) directly with ``pix_fmt="cuda"`` by adopting the frame's ``hw_frames_ctx`` before opening the encoder by :gh-user:`WyattBlue` (:issue:`2199`).
-- Fix a crash when reading ``VideoCodecContext.pix_fmt`` before it is set; it now returns ``None`` by :gh-user:`CarlosRDomin`.
-- Preserve frame attributes (``pts``, ``time_base``, colorspace, etc.) when downloading hardware frames to system memory by :gh-user:`CarlosRDomin`.
-
-v17.1.0
--------
-
-Breaking:
-
-- Remove the undertested ``av.option`` and ``av.descriptor`` APIs, along with the related ``Codec`` and ``Filter`` descriptor accessors.
-
-Features:
-
-- Use FFmpeg 8.1.1 in the binary wheels by :gh-user:`WyattBlue`.
-- Build Linux ARMv7 binary wheels by :gh-user:`WyattBlue`.
-- Expose ``AVCodecContext.global_quality`` by :gh-user:`WyattBlue` in (:pr:`2246`).
-- Expose ``Stream.discard`` so demuxing and seeking can skip unwanted streams by :gh-user:`WyattBlue` (:issue:`2272`).
-- Add ``Stream.set_display_matrix()`` and ``Stream.set_display_rotation()`` to write the container display (rotation) matrix on output streams by :gh-user:`hmaarrfk` in (:pr:`2287`).
-- Add ``Container.video_codec_id`` to force a specific video codec on a container by :gh-user:`WyattBlue` (:issue:`2243`).
-
-Fixes:
-
-- Add ``cython.final`` to leaf classes, ensuring that they are not subclassed by :gh-user:`WyattBlue`.
-- Warn that ``CodecContext.decode()`` is not memory safe in some cases.
-- Fix memory leaks in ``FFmpegError``, ``AudioLayout`` channel layouts, and ``Frame.opaque``, and break a reference cycle between ``FilterLink`` and ``Graph`` by :gh-user:`lgeiger`.
-- Reduce excessive logging lock contention by :gh-user:`WyattBlue` (:issue:`2276`).
-- Fix a crash when accessing ``Stream`` from multiple threads under FFmpeg 8.1 by :gh-user:`WyattBlue` (:issue:`2247`).
-- Fix a crash during ``InputContainer`` initialization by :gh-user:`WyattBlue` (:issue:`2010`).
-- Fix ``enumerate_input_devices`` and ``enumerate_output_devices`` raising ``AttributeError`` by :gh-user:`WyattBlue` and :gh-user:`kazuki` (:issue:`2264`).
-- Map HTTP 429 to ``HTTPTooManyRequestsError`` instead of ``UndefinedError`` by :gh-user:`WyattBlue` (:issue:`2267`).
-- Fix crash in ``VideoFrame.to_ndarray()`` and ``to_image()`` on bottom-up frames with a negative ``line_size`` by :gh-user:`WyattBlue` (:issue:`2213`).
-- Make ``Disposition`` an ``IntFlag`` so ``Stream.disposition`` can be assigned without raising ``TypeError`` by :gh-user:`HotariTobu`.
-- Assign parser-inferred ``pts``, ``dts``, and ``duration`` to packets from ``CodecContext.parse()`` by :gh-user:`WyattBlue` (:issue:`1919`).
-- Copy ``time_base`` in ``add_stream_from_template()`` by :gh-user:`daveisfera` in (:pr:`2249`).
-- Fix the remux examples dropping keyframes that demux with no DTS, which produced audio-only output by :gh-user:`WyattBlue` (:issue:`1917`).
-- Fix subtitle UTF-8 handling by :gh-user:`jbree` in (:pr:`2271`).
-- Fix several incorrect ``malloc`` size calculations by :gh-user:`WyattBlue`.
-
-v17.0.1
--------
-
-Fixes:
-
-- A cdivision decorator for faster division.
-- Adjust tests so they work with 8.1 by :gh-user:`strophy`.
-- Make VideoFormat.components lazy by :gh-user:`WyattBlue`.
-- Break reference cycle ``StreamContainer.get()`` by :gh-user:`lgeiger`.
-- Expose threads in filter graph by :gh-user:`lgeiger`.
-- Fix crash with container closing with GC by :gh-user:`WyattBlue`.
-- Fix "Writing packets to data stream broken in av>=17" regression :issue:`2223` by :gh-user:`WyattBlue`.
-- Remove ``_send_packet_and_recv`` to simplify ``decode()`` by :gh-user:`lgeiger`.
-- Reuse a ``AVPacket`` read buffer when demuxing by :gh-user:`lgeiger` and :gh-user:`WyattBlue`.
-- Use ``AVCodecContext.frame_num`` instead of counting ourselves by :gh-user:`WyattBlue`.
-- Use ``av_channel_layout_compare()`` for ``AudioLayout.__eq__()`` by :gh-user:`WyattBlue`.
-
-v17.0.0
--------
-
-Major:
-
-- Limited API binary wheels are now built.
-- 3.13t (free-threading) will be dropped because of storage limitations.
-- When an FFmpeg C function indicates an error, raise av.ArgumentError instead of ValueError/av.ValueError. This helps disambiguate why an exception is being thrown.
-- Save space by removing libaom (av1 encoder/decoder); dav1d, stvav1, and hardware, are available alternatives.
-
-Features:
-
-- Add ``OutputContainer.add_mux_stream()`` for creating codec-context-free streams, enabling muxing of pre-encoded packets without an encoder, addressing :issue:`1970` by :gh-user:`WyattBlue`.
-- Use zero-copy for Packet init from buffer data by :gh-user:`WyattBlue` in (:pr:`2199`).
-- Expose AVIndexEntry by :gh-user:`Queuecumber` in (:pr:`2136`).
-- Preserving hardware memory during cuvid decoding, exporting/importing via dlpack by :gh-user:`WyattBlue` in (:pr:`2155`).
-- Add enumerate_input_devices and enumerate_output_devices API by :gh-user:`WyattBlue` in (:pr:`2174`).
-- Add ``ColorTrc`` and ``ColorPrimaries`` enums; add ``color_trc`` and ``color_primaries`` properties to ``VideoFrame``; add ``dst_color_trc`` and ``dst_color_primaries`` parameters to ``VideoFrame.reformat()``, addressing :issue:`1968` by :gh-user:`WyattBlue` in (:pr:`2175`).
-- Add multithreaded reformatting and reduce Python overhead by replacing ``sws_scale`` with ``sws_scale_frame``, skipping unnecessary reformats, and minimizing Python interactions by :gh-user:`lgeiger`.
-- Prevent data copy in ``VideoFrame.to_ndarray()`` for padded frames by :gh-user:`lgeiger` in (:pr:`2190`).
-
-Fixes:
-
-- Fix :issue:`2149` by :gh-user:`WyattBlue` in (:pr:`2155`).
-- Fix packet typing based on stream and specify InputContainer.demux based on incoming stream by :gh-user:`ntjohnson1` in (:pr:`2134`).
-- Fix memory growth when remuxing with ``add_stream_from_template`` by skipping ``avcodec_open2`` for template-initialized codec contexts, addressing :issue:`2135` by :gh-user:`WyattBlue`.
-- Explicitly disable OpenSSL in source builds (``scripts/build-deps``) to prevent accidental OpenSSL linkage that breaks FIPS-enabled systems, addressing :issue:`1972`.
-- Add missing ``SWS_SPLINE`` interpolation by :gh-user:`lgeiger` in (:pr:`2188`).
-
-v16.1.0
--------
-
-Features:
-
-- Add support for Intel QSV codecs by :gh-user:`ladaapp`.
-- Add AMD AMF hardware decoding by :gh-user:`ladaapp2`.
-- Add subtitle encoding support by :gh-user:`skeskinen` in (:pr:`2050`).
-- Add read/write access to PacketSideData by :gh-user:`skeskinen` in (:pr:`2051`).
-- Add yuv422p support for video frame to_ndarray and from_ndarray by :gh-user:`wader` in (:pr:`2054`).
-- Add binding for ``avcodec_find_best_pix_fmt_of_list()`` by :gh-user:`ndeybach` in (:pr:`2058`).
-
-Fixes:
-
-- Fix #2036, #2053, #2057 by :gh-user:`WyattBlue`.
-
-v16.0.1
--------
-
-Fixes:
-
-- Add new hwaccel enums by :gh-user:`WyattBlue` in (:pr:`2030`).
-
-v16.0.0
--------
-
-Major:
-
-- Drop Python 3.9, Support Python 3.14.
-- Drop support for i686 Linux.
-
-Features:
-
-- Add ``Filter.Context.process_command()`` method by :gh-user:`caffeinism` in (:pr:`2000`).
-- Add packet side-data handling mechanism by :gh-user:`tikuma-lsuhsc` in (:pr:`2003`).
-- Implemented set_chapters method by :gh-user:`DE-AI` in (:pr:`2004`).
-- Declare free-threaded support and support 3.13t by :gh-user:`ngoldbaum` in (:pr:`2005`).
-- Add writable and copyable attachment and data streams by :gh-user:`skeskinen` in (:pr:`2026`).
-
-Fixes:
-
-- Declare free-threaded support and support 3.13t by :gh-user:`ngoldbaum` in (:pr:`2005`).
-- Allow ``None`` in ``FilterContext.push()`` type stub by :gh-user:`velsinki` in (:pr:`2015`).
-- Fix typos
-
-15.X and Below
+18.X and Below
 --------------
 ..
   or see older git commits
 
-`15.X Changelog <https://pyav.basswood.io/docs/15.1/development/changelog.html>`
+`18.X Changelog <https://pyav.basswood.io/docs/18.1/development/changelog.html>`
diff --git a/av/about.py b/av/about.py
@@ -1 +1 @@
-__version__ = "18.1.0"
+__version__ = "19.0.0pre1"