32. [1] Ting Zhang, Guo-Jun Qi, Bin Xiao, Jingdong Wang: Interleaved Group Convolutions. ICCV 2017: 4383-4392
[2] Guotian Xie, Jingdong Wang, Ting Zhang, Jianhuang Lai, Richang Hong, and Guo-JunQi. IGCV2: Interleaved Structured Sparse Convolutional Neural Networks. CVPR 2018.
[3] Ke Sun, Mingjie Li, Dong Liu, and Jingdong Wang. IGCV3: Interleaved Low-Rank Group Convolutions for Efficient Deep Neural Networks. BMVC 2018. 33
33. IGCV1: Interleaved group convolutions for large models
Ting Zhang, Guo-Jun Qi, Bin Xiao, Jingdong Wang: Interleaved Group Convolutions, ICCV 2017.
34
44. • Primary group convolution
• Secondary group convolution
Regular convolutions are interleaved group convolutions
Primary
Secondary
W11 W12 W21 W22
+ +
W
45
57. Design:
Balance condition minimum total #parameters, three conditions hold:
1) #parameters for (𝐿 − 1) group convolutions are the same
2) #branches for (𝐿 − 1) group convolutions are the same
3) #channels in each branch are the same
How to design 𝐿 group convolutions
#channels in each branch: 𝐾2 = ⋯ = 𝐾𝐿 = 𝐶
1
𝐿−1 = 𝐾
width
IGC block: 1 channel-wise 3 × 3 convolution + (𝐿 − 1) group 1 × 1 convolutions
61
59. #parameters When balance condition holds
3 × 3 1 × 1
How many group convolutions?
𝐿 = log 𝐶 + 1 so that 𝑄 is minimum
Benefit: Further redundancy reduction by composing more (𝐿 > 2) sparse matrices
𝑄 𝐿 = 3 < 𝑄 𝐿 = 2 if 𝐶 > 4
64
69. IGCV3: Interleaved Low-Rank Group Convolutions
Ke Sun, Mingjie Li, Dong Liu, and Jingdong Wang. IGCV3: Interleaved Low-Rank Group Convolutions for Efficient Deep Neural
Networks. BMVC 2018.
76
72. Ke Sun, Mingjie Li, Dong Liu, and Jingdong Wang. IGCV3: Interleaved Low-Rank Group Convolutions for Efficient Deep Neural
Networks. BMVC 2018.
small
IGCV3
79
80. Session 2: High-Resolution Representation Learning
Ke Sun, Bin Xiao, Dong Liu, Jingdong Wang: Deep High-Resolution Representation Learning for Human Pose Estimation. CVPR 2019
Ke Sun, Yang Zhao, Borui Jiang, Tianheng Cheng, Bin Xiao, Dong Liu, Yadong Mu, Xinggang Wang, Wenyu Liu, Jingdong Wang: High-Resolution
Representation Learning for labeling pixels and regions (Journal extension).
81. 92
Wider - more channels
Deeper - more layers
Finer -
higher resolution
→ finer
New dimension: go finer towards high-resolution representation learning
deeper → wider
83. 94
Low resolution
is enough
image recog. pixel-level recog.region-level recog.
The high-resolution representation is needed
global position-sensitive
92. 107
series
• Recover from low-resolution representations
• Repeat fusions across resolutions to strengthen high- & low-resolution
representations
parallel
Maintain through the whole process
HRNet can learn high-resolution strong representations