ECA-Net: Efficient Channel Attention

ECA-Net: Efficient Channel Attention for Deep Convolutional Neural Networks.

This is an implementation of ECA-Net, created by Banggu Wu.

Channel attention has recently demonstrated to offer great potential in improving the performance of deep convolutional neural networks (CNNs). However, most existing methods dedicate to developing more sophisticated attention modules to achieve better performance, inevitably increasing the computational burden. To overcome the paradox of performance and complexity trade-off, this paper makes an attempt to investigate an extremely lightweight attention module for boosting the performance of deep CNNs. In particular, we propose an Efficient Channel Attention (ECA) module, which only involves k (k<=9) parameters but brings clear performance gain. By revisiting the channel attention module in SENet, we empirically show avoiding dimensionality reduction and appropriate cross-channel interaction are important to learn effective channel attention. Therefore, we propose a local cross-channel interaction strategy without dimension reduction, which can be efficiently implemented by a fast 1D convolution. Furthermore, we develop a function of channel dimension to adaptively determine kernel size of 1D convolution, which stands for coverage of local cross-channel interaction. Our ECA module can be flexibly incorporated into existing CNN architectures, and the resulting CNNs are named by ECA-Net.We extensively evaluate the proposed ECA-Net on image classification, object detection and instance segmentation with backbones of ResNets and MobileNetV2. The experimental results show our ECA-Net is more efficient while performing favorably against its counterparts.


   title={ECA-Net: Efficient Channel Attention for Deep Convolutional Neural Networks},
   author={Qilong Wang, Banggu Wu, Pengfei Zhu, Peihua Li, Wangmeng Zuo and Qinghua Hu},

ECA module


Comparison of (a) SE block and (b) our efficient channel attention (ECA) module. Given the aggregated feature using global average pooling (GAP), SE block computes weights using two FC layers. Differently, ECA generates channel weights by performing a fast 1D convolution of size k, where k is adaptively determined via a function of channel dimension C.



  • Python 3.5+
  • PyTorch 1.0+
  • thop

Our environments

  • OS: Ubuntu 16.04
  • CUDA: 9.0/10.0
  • Toolkit: PyTorch 1.0/1.1
  • GPU: GTX 2080Ti/TiTan XP

Start Up

Train with ResNet

You can run the to train or evaluate as follow:

CUDA_VISIBLE_DEVICES={device_ids} python main -a {model_name} --ksize {eca_kernel_size} {the path of you datasets}

For example:

CUDA_VISIBLE_DEVICES=0,1,2,3 python main -a eca_resnet50 --ksize 3557 ./datasets/ILSVRC2012/images

Train with MobileNet_v2

It is same with above ResNet replace by

Compute the parameters and FLOPs

If you have install thop, you can to compute the parameters and FLOPs of our models. The usage is below:

python -a {model_name}



Model Param. FLOPs Top-1(%) Top-5(%) Pre trained models Extract code
ECA-Net50 24.37M 3.86G 77.48 93.68 eca_resnet50_k3557 7qo9
ECA-Net101 42.49M 7.35G 78.65 94.34 eca_resnet101_k3357 mvg2
ECA-Net152 57.41M 10.83G 78.92 94.55 eca_resnet152_k3357 ysh9
ECA-MobileNet_v2 3.34M 319.9M 72.56 90.81 eca_mobilenetv2_k13 atpt

COCO 2017

Detection with Faster R-CNN and Mask R-CNN

Model Param. FLOPs AP AP_50 AP_75 Pre trained models Extract code
Fast_R-CNN_ecanet50 41.53M 207.18G 38.0 60.6 40.9 faster_rcnn_ecanet50_k5_bs8_lr0.01 pmq9
Fast_R-CNN_ecanet101 60.52M 283.32G 40.3 62.9 44.0 faster_rcnn_ecanet101_3357_bs8_lr0.01 yk8o
Mask_R-CNN_ecanet50 44.18M 275.69G 39.0 61.3 42.1 mask_rcnn_ecanet50_k3377_bs8_lr0.01 gbx2
Mask_R-CNN_ecanet101 63.17M 351.83G 41.3 63.1 44.8 mask_rcnn_ecanet101_k3357_bs8_lr0.01 wywx

Instance segmentation with Mask R-CNN

Model Param. FLOPs AP AP_50 AP_75 Pre trained models Extract code
Mask_R-CNN_ecanet50 44.18M 275.69G 35.6 58.1 37.7 mask_rcnn_ecanet50_k3377_bs8_lr0.01 gbx2
Mask_R-CNN_ecanet101 63.17M 351.83G 37.4 59.9 39.8 mask_rcnn_ecanet101_k3357_bs8_lr0.01 wywx