---
license: apache-2.0
language:
- en
- zh
metrics:
- cer
pipeline_tag: automatic-speech-recognition
---
## Efficient Conformer v2 for non-streaming ASR

**Specification**: https://github.com/wenet-e2e/wenet/pull/1636

## Aishell-1 Results

* Feature info:
    * using fbank feature, cmvn, speed perturb, dither
* Training info:
    * [train_u2++_efficonformer_v2.yaml](https://github.com/wenet-e2e/wenet/blob/main/examples/aishell/s0/conf/train_u2%2B%2B_efficonformer_v2.yaml)
    * 8 gpu, batch size 16, acc_grad 1, 200 epochs
    * lr 0.001, warmup_steps 25000
* Model info:
    * Model Params: 49,354,651
    * Downsample rate: 1/2 (conv2d2) * 1/4 (efficonformer block)
    * encoder_dim 256, output_size 256, head 8, linear_units 2048
    * num_blocks 12, cnn_module_kernel 15, group_size 3
* Decoding info:
    * ctc_weight 0.5, reverse_weight 0.3, average_num 20

| decoding mode          | full | 18   | 16   |
|------------------------|------|------|------|
| attention decoder      | 4.87 | 5.03 | 5.07 |
| ctc prefix beam search | 4.97 | 5.18 | 5.20 |
| attention rescoring    | 4.56 | 4.75 | 4.77 |

## Start to Use

Install **WeNet** follow: https://wenet.org.cn/wenet/install.html#install-for-training


Decode

```sh
cd wenet/examples/aishell/s0
dir=exp/wenet_efficient_conformer_aishell_v2/

ctc_weight=0.5
reverse_weight=0.3
decoding_chunk_size=-1
mode="attention_rescoring"

test_dir=$dir/test_${mode}
mkdir -p $test_dir

# Decode
nohup python wenet/bin/recognize.py --gpu 0 \
    --mode $mode \
    --config $dir/train.yaml \
    --data_type "raw" \
    --test_data data/test/data.list \
    --checkpoint $dir/final.pt \
    --beam_size 10 \
    --batch_size 1 \
    --penalty 0.0 \
    --dict $dir/words.txt \
    --ctc_weight $ctc_weight \
    --reverse_weight $reverse_weight \
    --result_file $test_dir/text \
    ${decoding_chunk_size:+--decoding_chunk_size $decoding_chunk_size} > logs/decode_aishell.log &

# CER
python tools/compute-cer.py --char=1 --v=1 \
      data/test/text $test_dir/text > $test_dir/cer.txt
```