TorchAudio 2.2.2 Release

This release is compatible with PyTorch 2.2.2 patch release. There are no new features added.

TorchAudio 2.2.1 Release

This release is compatible with PyTorch 2.2.1 patch release. There are no new features added.

TorchAudio 2.2.0 Release

New Features

• Add path-like object support to StreamReader/Writer #3608
• Introduce trio top-level module, dedicated for core I/O operations (#3676, #3680, #3681, #3682) Please refer to https://pytorch.org/audio/2.2.0/torio.html for the details.

Bug Fixes

• #3685 Make F.vad return empty tensor for zero valued tensor input

Recipe Updates

• #3631 Fix inconsistent naming

TorchAudio 2.1.2 Release

This is a patch release, which is compatible with PyTorch 2.1.2. There are no new features added.

v2.1.1

This is a minor release, which is compatible with PyTorch 2.1.1 and includes bug fixes, improvements and documentation updates.

Bug Fixes

• Cherry-pick 2.1.1: Fix WavLM bundles (#3665)
• Cherry-pick 2.1.1: Add back compression level in i/o dispatcher backend by (#3666)

Torchaudio 2.1 Release Note

Hilights

TorchAudio v2.1 introduces the new features and backward-incompatible changes;

1. [BETA] A new API to apply filter, effects and codec
   torchaudio.io.AudioEffector can apply filters, effects and encodings to waveforms in online/offline fashion.
   You can use it as a form of augmentation.
   Please refer to https://pytorch.org/audio/2.1/tutorials/effector_tutorial.html for the examples.
2. [BETA] Tools for forced alignment
   New functions and a pre-trained model for forced alignment were added.
   torchaudio.functional.forced_align computes alignment from an emission and torchaudio.pipelines.MMS_FA provides access to the model trained for multilingual forced alignment in MMS: Scaling Speech Technology to 1000+ languages project.
   Please refer to https://pytorch.org/audio/2.1/tutorials/ctc_forced_alignment_api_tutorial.html for the usage of forced_align function, and https://pytorch.org/audio/2.1/tutorials/forced_alignment_for_multilingual_data_tutorial.html for how one can use MMS_FA to align transcript in multiple languages.
3. [BETA] TorchAudio-Squim : Models for reference-free speech assessment
   Model architectures and pre-trained models from the paper TorchAudio-Squim: Reference-less Speech Quality and Intelligibility measures in TorchAudio were added.
   You can use torchaudio.pipelines.SQUIM_SUBJECTIVE and torchaudio.pipelines.SQUIM_OBJECTIVE models to estimate the various speech quality and intelligibility metrics. This is helpful when evaluating the quality of speech generation models, such as TTS.
   Please refer to https://pytorch.org/audio/2.1/tutorials/squim_tutorial.html for the detail.
4. [BETA] CUDA-based CTC decoder
   torchaudio.models.decoder.CUCTCDecoder takes emission stored in CUDA memory and performs CTC beam search on it in CUDA device. The beam search is fast. It eliminates the need to move data from CUDA device to CPU when performing automatic speech recognition. With PyTorch's CUDA support, it is now possible to perform the entire speech recognition pipeline in CUDA.
   Please refer to https://pytorch.org/audio/2.1/tutorials/asr_inference_with_cuda_ctc_decoder_tutorial.html for the detail.
5. [Prototype] Utilities for AI music generation
   We are working to add utilities that are relevant to music AI. Since the last release, the following APIs were added to the prototype.
   Please refer to respective documentation for the usage.
   • torchaudio.prototype.chroma_filterbank
   • torchaudio.prototype.transforms.ChromaScale
   • torchaudio.prototype.transforms.ChromaSpectrogram
   • torchaudio.prototype.pipelines.VGGISH
6. New recipes for training models.
   Recipes for Audio-visual ASR, multi-channel DNN beamforming and TCPGen context-biasing were added.
   Please refer to the recipes
   • https://github.com/pytorch/audio/tree/release/2.1/examples/avsr
   • https://github.com/pytorch/audio/tree/release/2.1/examples/dnn_beamformer
   • https://github.com/pytorch/audio/tree/release/2.1/examples/asr/librispeech_conformer_rnnt_biasing
7. Update to FFmpeg support
   The version of supported FFmpeg libraries was updated.
   TorchAudio v2.1 works with FFmpeg 6, 5 and 4.4. The support for 4.3, 4.2 and 4.1 are dropped.
   Please refer to https://pytorch.org/audio/2.1/installation.html#optional-dependencies for the detail of the new FFmpeg integration mechanism.
8. Update to libsox integration
   TorchAudio now depends on libsox installed separately from torchaudio. Sox I/O backend no longer supports file-like object. (This is supported by FFmpeg backend and soundfile)
   Please refer to https://pytorch.org/audio/2.1/installation.html#optional-dependencies for the detail.

New Features

I/O

• Support overwriting PTS in torchaudio.io.StreamWriter (#3135)
• Include format information after filter torchaudio.io.StreamReader.get_out_stream_info (#3155)
• Support CUDA frame in torchaudio.io.StreamReader filter graph (#3183, #3479)
• Support YUV444P in GPU decoder (#3199)
• Add additional filter graph processing to torchaudio.io.StreamWriter (#3194)
• Cache and reuse HW device context in GPU decoder (#3178)
• Cache and reuse HW device context in GPU encoder (#3215)
• Support changing the number of channels in torchaudio.io.StreamReader (#3216)
• Support encode spec change in torchaudio.io.StreamWriter (#3207)
• Support encode options such as compression rate and bit rate (#3179, #3203, #3224)
• Add 420p10le support to torchaudio.io.StreamReader CPU decoder (#3332)
• Support multiple FFmpeg versions (#3464, #3476)
• Support writing opus and mp3 with soundfile (#3554)
• Add switch to disable sox integration and ffmpeg integration at runtime (#3500)

Ops

• Add torchaudio.io.AudioEffector (#3163, #3372, #3374)
• Add torchaudio.transforms.SpecAugment (#3309, #3314)
• Add torchaudio.functional.forced_align (#3348, #3355, #3533, #3536, #3354, #3365, #3433, #3357)
• Add torchaudio.functional.merge_tokens (#3535, #3614)
• Add torchaudio.functional.frechet_distance (#3545)

Models

• Add torchaudio.models.SquimObjective for speech enhancement (#3042, 3087, #3512)
• Add torchaudio.models.SquimSubjective for speech enhancement (#3189)
• Add torchaudio.models.decoder.CUCTCDecoder (#3096)

Pipelines

• Add torchaudio.pipelines.SquimObjectiveBundle for speech enhancement (#3103)
• Add torchaudio.pipelines.SquimSubjectiveBundle for speech enhancement (#3197)
• Add torchaudio.pipelines.MMS_FA Bundle for forced alignment (#3521, #3538)

Tutorials

• Add tutorial for torchaudio.io.AudioEffector (#3226)
• Add tutorials for CTC forced alignment API (#3356, #3443, #3529, #3534, #3542, #3546, #3566)
• Add tutorial for torchaudio.models.decoder.CUCTCDecoder (#3297)
• Add tutorial for real-time av-asr (#3511)
• Add tutorial for TorchAudio-SQUIM pipelines (#3279, #3313)
• Split HW acceleration tutorial into nvdec/nvenc tutorials (#3483, #3478)

Recipe

• Add TCPGen context-biasing Conformer RNN-T (#2890)
• Add AV-ASR recipe (#3278, #3421, #3441, #3489, #3493, #3498, #3492, #3532)
• Add multi-channel DNN beamforming training recipe (#3036)

Backward-incompatible changes

Third-party libraries

In this release, the following third party libraries are removed from TorchAudio binary distributions. TorchAudio now search and link these libraries at runtime. Please install them to use the corresponding APIs.

SoX

libsox is used for various audio I/O, filtering operations.

Pre-built binaries are avaialble via package managers, such as conda, apt and brew. Please refer to the respective documetation.

The APIs affected include;

• torchaudio.load ("sox" backend)
• torchaudio.info ("sox" backend)
• torchaudio.save ("sox" backend)
• torchaudio.sox_effects.apply_effects_tensor
• torchaudio.sox_effects.apply_effects_file
• torchaudio.functional.apply_codec (also deprecated, see below)

Changes related to the removal: #3232, #3246, #3497, #3035

Flashlight Text

flashlight-text is the core of CTC decoder.

Pre-built packages are available on PyPI. Please refer to https://github.com/flashlight/text for the detail.

The APIs affected include;

• torchaudio.models.decoder.CTCDecoder

Changes related to the removal: #3232, #3246, #3236, #3339

Kaldi

A custom built libkaldi was used to implement torchaudio.functional.compute_kaldi_pitch. This function, along with libkaldi integration, is removed in this release. There is no replcement.

Changes related to the removal: #3368, #3403

I/O

• Switch to the backend dispatcher (#3241)

To make I/O operations more flexible, TorchAudio introduced the backend dispatcher in v2.0, and users could opt-in to use the dispatcher.
In this release, the backend dispatcher becomes the default mechanism for selecting the I/O backend.

You can pass backend argument to torchaudio.info, torchaudio.load and torchaudio.save function to select I/O backend library per-call basis. (If it is omitted, an available backend is automatically selected.)

If you want to use the global backend mechanism, you can set the environment variable, TORCHAUDIO_USE_BACKEND_DISPATCHER=0.
Please note, however, that this the global backend mechanism is deprecated and is going to be removed in the next release.

Please see #2950 for the detail of migration work.

• Remove Tensor binding from StreamReader (#3093, #3272)

torchaudio.io.StreamReader accepted a byte-string wrapped in 1D torch.Tensor object. This is no longer supported.
Please wrap the underlying data with io.BytesIO instead.

• Make I/O optional arguments kw-only (#3208, #3227)

The optional arguments of add_[audio|video]_stream methods of torchaudio.io.StreamReader and torchaudio.io.StreamWriter are now keyword-only arguments.

• Drop the support of FFmpeg < 4.1 (#3561, 3557)

Previously TorchAudio supported FFmpeg 4 (>=4.1, <=4.4). In this release, TorchAudio supports FFmpeg 4, 5 and 6 (>=4.4, <7). With this change, support for FFmpeg 4.1, 4.2 and 4.3 are dropped.

Ops

• Use named file in torchaudio.functional.apply_codec (#3397)

In previous versions, TorchAudio shipped custom built libsox, so that it can perform in-memory decoding and encoding.
Now, in-memory decoding and encoding are handled by FFmpeg binding, and with the switch to dynamic libsox linking, torchaudio.functional.apply_codec no longer process audio in in-memory fashion. Instead it writes to temporary file.
For in-memory processing, please use torchaudio.io.AudioEffector.

• Switch to lstsq when solving InverseMelScale (#3280)

Previously, torchaudio.transform.InverseMelScale ran SGD optimizer to find the inverse of mel-scale transfo...

v2.0.2

TorchAudio 2.0.2 Release Note

This is a minor release, which is compatible with PyTorch 2.0.1 and includes bug fixes, improvements and documentation updates. There is no new feature added.

Bug fix

• #3239 Properly set #samples passed to encoder (#3204)
• #3238 Fix virtual function issue with CTC decoder (#3230)
• #3245 Fix path-like object support in FFmpeg dispatcher (#3243, #3248)
• #3261 Use scaled_dot_product_attention in Wav2vec2/HuBERT's SelfAttention (#3253)
• #3264 Use scaled_dot_product_attention in WavLM attention (#3252, #3265)

Full Changelog: v2.0.1...v2.0.2

Torchaudio 2.0 Release Note

Highlights

TorchAudio 2.0 release includes:

• Data augmentation operators, e.g. convolution, additive noise, speed perturbation
• WavLM and XLS-R models and pre-trained pipelines
• Backend dispatcher powering revised info, load, save functions
• Dropped support of Python 3.7
• Added Python 3.11 support

[Beta] Data augmentation operators

The release adds several data augmentation operators under torchaudio.functional and torchaudio.transforms:

• torchaudio.functional.add_noise
• torchaudio.functional.convolve
• torchaudio.functional.deemphasis
• torchaudio.functional.fftconvolve
• torchaudio.functional.preemphasis
• torchaudio.functional.speed
• torchaudio.transforms.AddNoise
• torchaudio.transforms.Convolve
• torchaudio.transforms.Deemphasis
• torchaudio.transforms.FFTConvolve
• torchaudio.transforms.Preemphasis
• torchaudio.transforms.Speed
• torchaudio.transforms.SpeedPerturbation

The operators can be used to synthetically diversify training data to improve the generalizability of downstream models.

For usage details, please refer to the documentation for torchaudio.functional and torchaudio.transforms, and tutorial “Audio Data Augmentation”.

[Beta] WavLM and XLS-R models and pre-trained pipelines

The release adds two self-supervised learning models for speech and audio.

• WavLM that is robust to noise and reverberation.
• XLS-R that is trained on cross-lingual datasets.

Besides the model architectures, torchaudio also supports corresponding pre-trained pipelines:

• torchaudio.pipelines.WAVLM_BASE
• torchaudio.pipelines.WAVLM_BASE_PLUS
• torchaudio.pipelines.WAVLM_LARGE
• torchaudio.pipelines.WAV2VEC_XLSR_300M
• torchaudio.pipelines.WAV2VEC_XLSR_1B
• torchaudio.pipelines.WAV2VEC_XLSR_2B

For usage details, please refer to factory function and pre-trained pipelines documentation.

Backend dispatcher

Release 2.0 introduces new versions of I/O functions torchaudio.info, torchaudio.load and torchaudio.save, backed by a dispatcher that allows for selecting one of backends FFmpeg, SoX, and SoundFile to use, subject to library availability. Users can enable the new logic in Release 2.0 by setting the environment variable TORCHAUDIO_USE_BACKEND_DISPATCHER=1; the new logic will be enabled by default in Release 2.1.

# Fetch metadata using FFmpeg
metadata = torchaudio.info("test.wav", backend="ffmpeg")

# Load audio (with no backend parameter value provided, function prioritizes using FFmpeg if it is available)
waveform, rate = torchaudio.load("test.wav")

# Write audio using SoX
torchaudio.save("out.wav", waveform, rate, backend="sox")

Please see the documentation for torchaudio for more details.

Backward-incompatible changes

• Dropped Python 3.7 support (#3020)
  Following the upstream PyTorch (pytorch/pytorch#93155), the support for Python 3.7 has been dropped.

• Default to "precise" seek in torchaudio.io.StreamReader.seek (#2737, #2841, #2915, #2916, #2970)
  Previously, the StreamReader.seek method seeked into a key frame closest to the given time stamp. A new option mode has been added which can switch the behavior to seeking into any type of frame, including non-key frames, that is closest to the given timestamp, and this behavior is now default.

• Removed deprecated/unused/undocumented functions from datasets.utils (#2926, #2927)
  The following functions are removed from datasets.utils

  • stream_url
  • download_url
  • validate_file
  • extract_archive.

Deprecations

Ops

• Deprecated 'onesided' init param for MelSpectrogram (#2797, #2799)
  torchaudio.transforms.MelSpectrogram assumes the onesided argument to be always True. The forward path fails if its value is False. Therefore this argument is deprecated. Users specifying this argument should stop specifying it.

• Deprecated "sinc_interpolation" and "kaiser_window" option value in favor of "sinc_interp_hann" and "sinc_interp_kaiser" (#2922)
  The valid values of resampling_method argument of resampling operations (torchaudio.transforms.Resample and torchaudio.functional.resample) are changed. "kaiser_window" is now "sinc_interp_kaiser" and "sinc_interpolation" is "sinc_interp_hann". The old values will continue to work, but users are encouraged to update their code.
  For the reason behind of this change, please refer #2891.

• Deprecated sox initialization/shutdown public API functions (#3010)
  torchaudio.sox_effects.init_sox_effects and torchaudio.sox_effects.shutdown_sox_effects are deprecated. They were required to use libsox-related features, but are called automatically since v0.6, and the initialization/shutdown mechanism have been moved elsewhere. These functions are now no-op. Users can simply remove the call to these functions.

Models

• Deprecated static binding of Flashlight-text based CTC decoder (#3055, #3089)
  Since v0.12, TorchAudio binary distributions included the CTC decoder based on flashlight-text project. In a future release, TorchAudio will switch to dynamic binding of underlying CTC decoder implementation, and stop shipping the core CTC decoder implementations. Users who would like to use the CTC decoder need to separately install the CTC decoder from the upstream flashlight-text project. Other functionalities of TorchAudio will continue to work without flashlight-text.
  Note: The API and numerical behavior does not change.
  For more detail, please refer #3088.

I/O

• Deprecated file-like object support in sox_io (#3033)
  As a preparation to switch to dynamically bound libsox, file-like object support in sox_io backend has been deprecated. It will be removed in 2.1 release in favor of the dispatcher. This deprecation affects the following functionalities.
  • I/O: torchaudio.load, torchaudio.info and torchaudio.save.
  • Effects: torchaudio.sox_effects.apply_effects_file and torchaudio.functional.apply_codec.
    For I/O, to continue using file-like objects, please use the new dispatcher mechanism.
    For effects, replacement functions will be added in the next release.
• Deprecated the use of Tensor as a container for byte string in StreamReader (#3086)
  torchaudio.io.StreamReader supports decoding media from byte strings contained in 1D tensors of torch.uint8 type. Using torch.Tensor type as a container for byte string is now deprecated. To pass byte strings, please wrap the string with io.BytesIO.

  Deprecated	Migration
  data = b"..." src = torch.frombuffer(data, dtype=torch.uint8) StreamReader(src)	data = b"..." src = io.BytesIO(data) StreamReader(src)

Bug Fixes

Ops

• Fixed contiguous error when backpropagating through torchaudio.functional.lfilter (#3080)

Pipelines

• Added layer normalization to wav2vec2 large+ pretrained models (#2873)
  In self-supervised learning models such as Wav2Vec 2.0, HuBERT, or WavLM, layer normalization should be applied to waveforms if the convolutional feature extraction module uses layer normalization and is trained on a large-scale dataset. After adding layer normalization to those affected models, the Word Error Rate is significantly reduced.

Without the change in #2873, the WER results are:

Model	dev-clean	dev-other	test-clean	test-other
WAV2VEC2_ASR_LARGE_LV60K_10M	10.59	15.62	9.58	16.33
WAV2VEC2_ASR_LARGE_LV60K_100H	2.80	6.01	2.82	6.34
WAV2VEC2_ASR_LARGE_LV60K_960H	2.36	4.43	2.41	4.96
HUBERT_ASR_LARGE	1.85	3.46	2.09	3.89
HUBERT_ASR_XLARGE	2.21	3.40	2.26	4.05

After applying layer normalization, the updated WER results are:
| Model | dev-clean | dev-other | test-clean | test-other |
|:---------------------------------------------------------------------------------...

TorchAudio 0.13.1 Release Note

This is a minor release, which is compatible with PyTorch 1.13.1 and includes bug fixes, improvements and documentation updates. There is no new feature added.

Bug Fix

IO

• Make buffer size configurable in ffmpeg file object operations and set size in backend (#2810)
• Fix issue with the missing video frame in StreamWriter (#2789)
• Fix decimal FPS handling StreamWriter (#2831)
• Fix wrong frame allocation in StreamWriter (#2905)
• Fix duplicated memory allocation in StreamWriter (#2906)

Model

• Fix HuBERT model initialization (#2846, #2886)

Recipe

• Fix issues in HuBERT fine-tuning recipe (#2851)
• Fix automatic mixed precision in HuBERT pre-training recipe (#2854)

torchaudio 0.13.0 Release Note

Highlights

TorchAudio 0.13.0 release includes:

• Source separation models and pre-trained bundles (Hybrid Demucs, ConvTasNet)
• New datasets and metadata mode for the SUPERB benchmark
• Custom language model support for CTC beam search decoding
• StreamWriter for audio and video encoding

[Beta] Source Separation Models and Bundles

Hybrid Demucs is a music source separation model that uses both spectrogram and time domain features. It has demonstrated state-of-the-art performance in the Sony Music DeMixing Challenge. (citation: https://arxiv.org/abs/2111.03600)

The TorchAudio v0.13 release includes the following features

• MUSDB_HQ Dataset, which is used in Hybrid Demucs training (docs)
• Hybrid Demucs model architecture (docs)
• Three factory functions suitable for different sample rate ranges
• Pre-trained pipelines (docs) and tutorial

SDR Results of pre-trained pipelines on MUSDB-HQ test set

Pipeline	All	Drums	Bass	Other	Vocals
HDEMUCS_HIGH_MUSDB*	6.42	7.76	6.51	4.47	6.93
HDEMUCS_HIGH_MUSDB_PLUS**	9.37	11.38	10.53	7.24	8.32

* Trained on the training data of MUSDB-HQ dataset.
** Trained on both training and test sets of MUSDB-HQ and 150 extra songs from an internal database that were specifically produced for Meta.

Special thanks to @adefossez for the guidance.

ConvTasNet model architecture was added in TorchAudio 0.7.0. It is the first source separation model that outperforms the oracle ideal ratio mask. In this release, TorchAudio adds the pre-trained pipeline that is trained within TorchAudio on the Libri2Mix dataset. The pipeline achieves 15.6dB SDR improvement and 15.3dB Si-SNR improvement on the Libri2Mix test set.

[Beta] Datasets and Metadata Mode for SUPERB Benchmarks

With the addition of four new audio-related datasets, there is now support for all downstream tasks in version 1 of the SUPERB benchmark. Furthermore, these datasets support metadata mode through a get_metadata function, which enables faster dataset iteration or preprocessing without the need to load or store waveforms.

Datasets with metadata functionality:

• LIBRISPEECH (docs)
• LibriMix (docs)
• QUESST14 (docs)
• SPEECHCOMMANDS (docs)
• (new) FluentSpeechCommands (docs)
• (new) Snips (docs)
• (new) IEMOCAP (docs)
• (new) VoxCeleb1 (Identification, Verification)

[Beta] Custom Language Model support in CTC Beam Search Decoding

In release 0.12, TorchAudio released a CTC beam search decoder with KenLM language model support. This release, there is added functionality for creating custom Python language models that are compatible with the decoder, using the torchaudio.models.decoder.CTCDecoderLM wrapper.

[Beta] StreamWriter

torchaudio.io.StreamWriter is a class for encoding media including audio and video. This can handle a wide variety of codecs, chunk-by-chunk encoding and GPU encoding.

Backward-incompatible changes

• [BC-breaking] Fix momentum in transforms.GriffinLim (#2568)
  The GriffinLim implementations in transforms and functional used the momentum parameter differently, resulting in inconsistent results between the two implementations. The transforms.GriffinLim usage of momentum is updated to resolve this discrepancy.
• Make torchaudio.info decode audio to compute num_frames if it is not found in metadata (#2740).
  In such cases, torchaudio.info may now return non-zero values for num_frames.

Bug Fixes

• Fix random Gaussian generation (#2639)
  torchaudio.compliance.kaldi.fbank with dither option produced a different output from kaldi because it used a skewed, rather than gaussian, distribution for dither. This is updated in this release to correctly use a random gaussian instead.
• Update download link for speech commands (#2777)
  The previous download link for SpeechCommands v2 did not include data for the valid and test sets, resulting in errors when trying to use those subsets. Update the download link to correctly download the whole dataset.

New Features

IO

• Add metadata to source stream info (#2461, #2464)
• Add utility function to fetch FFmpeg library versions (#2467)
• Add YUV444P support to StreamReader (#2516)
• Add StreamWriter (#2628, #2648, #2505)
• Support in-memory decoding via Tensor wrapper in StreamReader (#2694)
• Add StreamReader Tensor Binding to src (#2699)
• Add StreamWriter media device/streaming tutorial (#2708)
• Add StreamWriter tutorial (#2698)

Ops

• Add ITU-R BS.1770-4 loudness recommendation (#2472)
• Add convolution operator (#2602)
• Add additive noise function (#2608)

Models

• Hybrid Demucs model implementation (#2506)
• Docstring change for Hybrid Demucs (#2542, #2570)
• Add NNLM support to CTC Decoder (#2528, #2658)
• Move hybrid demucs model out of prototype (#2668)
• Move conv_tasnet_base doc out of prototype (#2675)
• Add custom lm example to decoder tutorial (#2762)

Pipelines

• Add SourceSeparationBundle to prototype (#2440, #2559)
• Adding pipeline changes, factory functions to HDemucs (#2547, #2565)
• Create tutorial for HDemucs (#2572)
• Add HDEMUCS_HIGH_MUSDB (#2601)
• Move SourceSeparationBundle and pre-trained ConvTasNet pipeline into Beta (#2669)
• Move Hybrid Demucs pipeline to beta (#2673)
• Update description of HDemucs pipelines

Datasets

• Add fluent speech commands (#2480, #2510)
• Add musdb dataset and tests (#2484)
• Add VoxCeleb1 dataset (#2349)
• Add metadata function for LibriSpeech (#2653)
• Add Speech Commands metadata function (#2687)
• Add metadata mode for various datasets (#2697)
• Add IEMOCAP dataset (#2732)
• Add Snips Dataset (#2738)
• Add metadata for Librimix (#2751)
• Add file name to returned item in Snips dataset (#2775)
• Update IEMOCAP variants and labels (#2778)

Improvements

IO

• Replace runtime_error exception with TORCH_CHECK (#2550, #2551, #2592)
• Refactor StreamReader (#2507, #2508, #2512, #2530, #2531, #2533, #2534)
• Refactor sox C++ (#2636, #2663)
• Delay the import of kaldi_io (#2573)

Ops

• Speed up resample with kernel generation modification (#2553, #2561)
  The kernel generation for resampling is optimized in this release. The following table illustrates the performance improvements from the previous release for the torchaudio.functional.resample function using the sinc resampling method, on float32 tensor with two channels and one second duration.

CPU

torchaudio version	8k → 16k [Hz]	16k → 8k	16k → 44.1k	44.1k → 16k
0.13	0.256	0.549	0.769	0.820
0.12	0.386	0.534	31.8	12.1

CUDA

torchaudio version	8k → 16k [Hz]	16k → 8k	16k → 44.1k	44.1k → 16k
0.13	0.332	0.336	0.345	0.381
0.12	0.524	0.334	64.4	22.8

• Add normalization parameter on spectrogram and inverse spectrogram (#2554)
• Replace assert with raise for ops (#2579, #2599)
• Replace CHECK_ by TORCH_CHECK_ (#2582)
• Fix argument validation in TorchAudio filtering (#2609)

Models

• Switch to flashlight decoder from upstream (#2557)
• Add dimension and shape check (#2563)
• Replace assert with raise in models (#2578, #2590)
• Migrate CTC decoder code (#2580)
• Enable CTC decoder in Windows (#2587)

Datasets

• Replace assert with raise in datasets (#2571)
• Add unit test for LibriMix dataset (#2659)
• Add gtzan download note (#2763)

Tutorials

• Tweak tutorials (#2630, #2733)
• Update ASR inference tutorial (#2631)
• Update and fix tutorials (#2661, #2701)
• Introduce IO section to getting started tutorials (#2703)
• Update HW video processing tutorial (#2739)
• Update tutorial author information (#2764)
• Fix typos in tacotron2 tutorial (#2761)
• Fix fading in hybrid demucs tutorial (#2771)
• Fix leaking matplotlib figure (#2769)
• Update resampling tutorial (#2773)

Recipes

• Use lazy import for joblib (#2498)
• Revise LibriSpeech Conformer RNN-T recipe (#2535)
• Fix bug in Conformer RNN-T recipe (#2611)
• Replace bg_iterator in examples (#2645)
• Remove obsolete examples (#2655)
• Fix LibriSpeech Conforner RNN-T eval script (#2666)
• Replace IValue::toString()->string() with IValue::toStringRef() (#2700)
• Improve wav2vec2/hubert model for pre-training (#2716)
• Improve hubert recipe for pre-training and fine-tuning (#2744)

WER improvement on LibriSpe...