Generative Adversarial Networks (GANs) are a type of deep learning model that has gained a lot of attention in recent years due to their ability to generate realistic images, videos, and other types of data.
One of the most significant challenges GANs face is mode collapse, where a GAN generates only a limited set of output examples instead of exploring the entire distribution of the training data.
There are several causes of mode collapse in GANs, including catastrophic forgetting and discriminator overfitting, both of which lead to the generator getting stuck in a particular mode or pattern.
Catastrophic forgetting refers to the phenomenon in which a model trained on a specific task forgets the knowledge it has gained while learning a new task.
Discriminator overfitting results in the generator loss vanishing, causing multiple flat regions to emerge, further leading to a decrease in the diversity of generated samples.
In order to prevent catastrophic forgetting, the model must be trained with multiple tasks simultaneously, while the local maxima should have a wide shape to prevent mode collapse.
The visualization of the surface of the discriminator shows that the generator produces similar outputs, indicating mode collapse, and the discriminator scores for images change between training steps.
GANs demonstrate the same catastrophic forgetting tendencies when trained on symmetric 2D datasets, as displayed in the visualizations of the surface of the discriminator.
To avoid discriminator overfitting and promote diversity in generated samples, local maxima in various regions of the data space should have a wide shape, and the generator should be trained on less specific targets.
By understanding the causes of mode collapse in GANs, we can allow them to better develop GANs that are capable of generating diverse and high-quality outputs.