CS5720 - Week 4
Slide 69 of 80

Pooling Operations: Max and Average Pooling

πŸŠβ€β™‚οΈ What is Pooling?

Pooling is a downsampling operation that reduces the spatial dimensions of feature maps while retaining important information. It operates on non-overlapping regions.
Key Characteristics:

β€’ Parameter-free: No learnable weights
β€’ Translation invariant: Small shifts don't change output much
β€’ Dimensionality reduction: Reduces spatial size
β€’ Feature selection: Keeps most important activations
βœ“ Reduces computational complexity
βœ“ Provides translation invariance
βœ“ Controls overfitting
βœ“ Increases receptive field

🎯 Types of Pooling

πŸ”₯ Max Pooling
Takes the maximum value from each region. Preserves the strongest activations and provides translation invariance.
πŸ“Š Average Pooling
Computes the average of all values in each region. Provides smoother downsampling with less information loss.
🌍 Global Pooling
Pools over the entire feature map, reducing it to a single value per channel. Used before final classification layers.
πŸŽ›οΈ Adaptive Pooling
Automatically adjusts pooling to produce a fixed output size regardless of input dimensions.

Interactive Pooling Demonstration

Input Feature Map (4Γ—4)
β†’
Max Pooling (2Γ—2, stride=2)
Click "Play" or "Next" to see pooling step by step
Prepared by Dr. Gorkem Kar