# Hugging Face Transformers v4.12.0 — Release & Upgrade Intelligence
- **Product:** Hugging Face Transformers (https://huggingface.co)
- **Version:** v4.12.0
- **Released:** Oct 28, 2021
- **Impact Score:** 5/10
- **Breaking Changes:** Not verified
- **Canonical Analysis:** https://changelogs.us/transformers/updates/v4.12.0/

## Executive Summary (TL;DR)
Hugging Face Transformers v4.12.0. Source highlight: TrOCR and VisionEncoderDecoderModel

## New Features
- Add TrOCR + VisionEncoderDecoderModel
- Add the SEW and SEW-D speech models
- Add SEW CTC models
- Add TFEncoderDecoderModel + Add cross-attention to some TF models
- Add DistilHuBERT
- [Speech Examples] Add pytorch speech pretraining

## Improvements
- [ASR] Make speech recognition example more general to load any tokenizer

## Bug Fixes
- Fix EncoderDecoderModel classes to be more like BART and T5 by @NielsRogge  in https://github.com/huggingface/transformers/pull/14139
- Fix filtering in test fetcher utils
- Fix warning for gradient_checkpointing
- Implement len in IterableDatasetShard
- [Wav2Vec2] Better error message
- Fix LayoutLM ONNX test error

## Upgrade Command
```bash
python -m pip install 'transformers==4.12.0'
```