Remove legacy backends (#1311)

Author: prabhat00155

docs/source/backend.rst

@@ -11,44 +11,18 @@ Overview
 There are currently four implementations available.
 
 * :ref:`"sox_io" <sox_io_backend>` (default on Linux/macOS)
-* :ref:`"sox" <sox_backend>` (deprecated, will be removed in 0.9.0 release)
 * :ref:`"soundfile" <soundfile_backend>` (default on Windows)
-* :ref:`"soundfile" (legacy interface) <soundfile_legacy_backend>` (deprecated, will be removed in 0.9.0 release)
-
-The use of ``"sox"`` backend is strongly discouraged as it cannot correctly handle formats other than 16-bit integer WAV. See `#726 <https://github.com/pytorch/audio/pull/726>`_ for the detail.
 
 .. note::
    Instead of calling functions in ``torchaudio.backend`` directly, please use ``torchaudio.info``, ``torchaudio.load``, ``torchaudio.load_wav`` and ``torchaudio.save`` with proper backend set with :func:`torchaudio.set_audio_backend`.
 
 Availability
 ------------
 
-``"sox"`` and ``"sox_io"`` backends require C++ extension module, which is included in Linux/macOS binary distributions. These backends are not available on Windows.
+``"sox_io"`` backend requires C++ extension module, which is included in Linux/macOS binary distributions. This backend is not available on Windows.
 
 ``"soundfile"`` backend requires ``SoundFile``. Please refer to `the SoundFile documentation <https://pysoundfile.readthedocs.io/en/latest/>`_ for the installation.
 
-Changes in default backend and deprecation
-------------------------------------------
-
-Backend module is going through a major overhaul. The following table summarizes the timeline for the deprecations and removals.
-
- +--------------------+-----------------------+------------------------+
- | **Backend**        | **0.8.0**             | **0.9.0**              |
- +====================+=======================+========================+
- | ``"sox_io"``       | Default on Linx/macOS | Default on Linux/macOS |
- +--------------------+-----------------------+------------------------+
- | ``"sox"``          | Available             | Removed                |
- | (deprecated)       |                       |                        |
- +--------------------+-----------------------+------------------------+
- | ``"soundfile"``    | Default on Windows    | Default on Windows     |
- +--------------------+-----------------------+------------------------+
- | ``"soundfile"``    | Available             | Removed                |
- | (legacy interface, |                       |                        |
- | deprecated)        |                       |                        |
- +--------------------+-----------------------+------------------------+
-
-* The ``"sox"`` and ``"soundfile" (legacy interface)`` backends are deprecated and will be removed in 0.9.0 release.
-
 Common Data Structure
 ~~~~~~~~~~~~~~~~~~~~~
 
@@ -59,16 +33,6 @@ AudioMetaData
 
 .. autoclass:: torchaudio.backend.common.AudioMetaData
 
-SignalInfo (Deprecated)
------------------------
-
-.. autoclass:: torchaudio.backend.common.SignalInfo
-
-EncodingInfo (Deprecated)
--------------------------
-
-.. autoclass:: torchaudio.backend.common.EncodingInfo
-
 .. _sox_io_backend:
 
 Sox IO Backend
@@ -102,44 +66,6 @@ save
 
 .. autofunction:: torchaudio.backend.sox_io_backend.save
 
-.. _sox_backend:
-
-Sox Backend (Deprecated)
-~~~~~~~~~~~~~~~~~~~~~~~~
-
-The ``"sox"`` backend is available on Linux/macOS and not available on Windows. This backend is deprecated and will be removed in ``0.9.0`` release.
-
-You can switch from another backend to ``sox`` backend with the following;
-
-.. code::
-
-   torchaudio.set_audio_backend("sox")
-
-info
-----
-
-.. autofunction:: torchaudio.backend.sox_backend.info
-
-load
-----
-
-.. autofunction:: torchaudio.backend.sox_backend.load
-
-.. autofunction:: torchaudio.backend.sox_backend.load_wav
-
-
-save
-----
-
-.. autofunction:: torchaudio.backend.sox_backend.save
-
-others
-------
-
-.. automodule:: torchaudio.backend.sox_backend
-   :members:
-   :exclude-members: info, load, load_wav, save
-
 .. _soundfile_backend:
 
 Soundfile Backend
@@ -153,55 +79,20 @@ You can switch from another backend to the ``"soundfile"`` backend with the foll
 
    torchaudio.set_audio_backend("soundfile")
 
-.. note::
-    If you are switching from `"soundfile" (legacy interface) <soundfile_legacy_backend>` backend, set ``torchaudio.USE_SOUNDFILE_LEGACY_INTERFACE`` flag **before** switching the backend.
-
 info
 ----
 
-.. autofunction:: torchaudio.backend._soundfile_backend.info
-
-load
-----
-
-.. autofunction:: torchaudio.backend._soundfile_backend.load
-
-.. autofunction:: torchaudio.backend._soundfile_backend.load_wav
-
-
-save
-----
-
-.. autofunction:: torchaudio.backend._soundfile_backend.save
-
-.. _soundfile_legacy_backend:
-
-Legacy Interface (Deprecated)
------------------------------
-
-``"soundfile"`` backend with legacy interface is made available for backward compatibility reason, however this interface is deprecated and will be removed in the ``0.9.0`` release.
-
-To switch to this backend/interface, set ``torchaudio.USE_SOUNDFILE_LEGACY_INTERFACE`` flag **before** switching the backend.
-
-.. code::
-
-   torchaudio.USE_SOUNDFILE_LEGACY_INTERFACE = True
-   torchaudio.set_audio_backend("soundfile")  # The legacy interface
-
-info
-^^^^
-
 .. autofunction:: torchaudio.backend.soundfile_backend.info
 
 load
-^^^^
+----
 
 .. autofunction:: torchaudio.backend.soundfile_backend.load
 
 .. autofunction:: torchaudio.backend.soundfile_backend.load_wav
 
 
 save
-^^^^
+----
 
 .. autofunction:: torchaudio.backend.soundfile_backend.save