A convolutional block is a repeated VGG unit that applies one or more 3 × 3 convolution layers, ReLU activations, and a 2 × 2 max-pooling step. Stacking these blocks builds a convolutional backbone for image classification. section 11.2.1
A block combines:
- A ReLU after every convolution, adding nonlinearity while retaining the small-filter design. section 11.2.1
VGG-11 configuration
A VGG-11 backbone uses five blocks: (3, 1, 64), (64, 1, 128), (128, 2, 256), (256, 2, 512), and (512, 2, 512). Each tuple specifies input channels, convolution count, and output features.
