All Stories

EfficientNet

EfficientNet's compound scaling rule, the FLOPs constraint that makes it work, the grid-searched constants, and the ImageNet accuracy it buys.

MobileNet Architecture

Why MobileNetV2 expands before it filters, what makes the residual inverted, and why the last layer of the block has no ReLU on it.

MobileNet

Depthwise separable convolution derived and costed: where the 1/N + 1/f-squared ratio comes from, and what an 8-9x saving actually looks like.

The Inception Network

How GoogLeNet stacks nine Inception modules into 6.8M parameters, what the auxiliary classifiers were really for, and what v2 and v3 changed.

Inception Network Motivation

Why the Inception module refuses to choose a filter size, and the 120M to 12.4M bottleneck arithmetic that makes running all of them affordable.

1x1 Convolutions and Network in Network

Why a 1x1 filter is not a no-op, how it becomes a per-pixel fully connected layer across channels, and the bottleneck it makes possible.