GAN
Neural Network which generates realistic data.
Motivation
- Stackgan generates images from text
- Pix2Pix generates realistic images from sketches
- Turn day scenes into night scenes
- CycleGAN
- Simulated eye images to Real images
How it works
- Consists of Generator and Discriminator
- Generator takes in noise and generates image
- Discriminator is a classifier which takes a real and a generated image and has to decide whether it's real or fake.
Tips and Tricks
- Use Leaky ReLu, important for gradient flow
- At least one hidden layer in G and D
- Generator output has tanh activation
- Discriminator has sigmoid activation
- Use Adam as optimizer
- Use logits for cross entropy
- Multiply labels times 0.9, helps discriminator to generalize better
- Generator gets random noise z as input
- Use Batchnorm everywhere except output layer of generator and input layer of descriminator
- Paper: Improved Techniques for Training GANs