计算机与现代化 ›› 2021, Vol. 0 ›› Issue (12): 13-18.

• 算法设计与分析 • 上一篇    下一篇

基于迁移学习的卷积神经网络通道剪枝

  

  1. (华北计算技术研究所,北京100083)
  • 出版日期:2021-12-24 发布日期:2021-12-24
  • 作者简介:冯敬翔(1997—),男,黑龙江哈尔滨人,硕士研究生,研究方向:深度神经网络与模型压缩,E-mail: qingkong10568@163.com。
  • 基金资助:
    国家自然科学基金资助项目(U19B2019)

Channel Pruning of Convolutional Neural Network Based on Transfer Learning

  1. (North China Institute of Computing Technology, Beijing 100083, China)
  • Online:2021-12-24 Published:2021-12-24

摘要: 卷积神经网络在计算机视觉等多个领域应用广泛,然而其模型参数量众多、计算开销庞大,导致许多边缘设备无法满足其存储与计算资源要求。针对其边缘部署困难,提出使用迁移学习策略改进基于BN层缩放因子通道剪枝方法的稀疏化过程。本文对比不同层级迁移方案对稀疏化效果与通道剪枝选取容限的影响;并基于网络结构搜索观点设计实验,探究其精度保持极限与迭代结构的收敛性。实验结果表明,对比原模型,采用迁移学习的通道剪枝算法,在精度损失不超过0.10的前提下,参数量减少89.1%,模型存储大小压缩89.3%;对比原剪枝方法,将剪枝阈值从0.85提升到0.97,进一步减少参数42.6%。实验证明,引入迁移策略更易实现充分的稀疏化,提高通道剪枝阈值选取容限,实现更高压缩率;并在迭代剪枝的网络结构搜索过程中,提供更高效的搜索起点,利于快速迭代趋近至搜索空间的一个网络结构局部最优解。

关键词: 卷积神经网络, 迁移学习, 通道剪枝, 网络结构搜索

Abstract: Convolutional neural networks are widely used in many fields like computer vision. However, large number of model parameters and huge cost make many edge devices unable to offer enough storage and computing resource. Aiming at problems above, a migration learning method is introduced to improve the sparsity proportion of the channel pruning method based on the scaling factor of the BN layer. The effects of different levels of migration on the sparsity proportion and channel pruning are compared, and  experiments based on the NAS viewpoint are designed  to explore its pruning accuracy limit and iterative structure convergence. The results show that compared with the original model, with the accuracy loss under 0.10, the parameter amount is reduced by 89.1%, and the model storage size is reduced by 89.3%. Compared with the original pruning method, the pruning threshold is increased from 0.85 to 0.97, further reducing the parametes by 42.6%. Experiments have proved that the introduction of migration method makes it easier to fully sparse the weights, increases the tolerance of the channel pruning threshold, and gets a higher compression rate. In the pruning network architecture search process, the migration provides a more efficient starting point to search, which seems easy to converge to a local optimal solution of the NAS.

Key words: convolutional neural network, migration learning, channel pruning, neural architecture search