Image recognition is classifying what an image contains. For example, a model can use image pixels as features to decide whether a picture contains a dog. section 5.5
A perceptron can perform reasonably on curated image datasets such as MNIST, which contains handwritten digits, but struggles with more complicated images. Combining perceptrons into a multilayer neural network supports more powerful classification. section 5.5
A neural-network image-classification example uses MNIST:
- Flatten each 28-by-28 image into a vector and convert its digit label into a 10-entry categorical vector. section 10.3
- Train a Keras network with two hidden layers to classify the digits, then use its predictions on test images. section 10.3
- Inspect results: the network classifies some digits correctly and mistakes others, such as a 3 predicted as an 8. section 10.3
See handwritten digit images alongside their labels. section 10.3

