Discrete autoencoder model for compressing pong frames.

def autoencoder_discrete_pong():
  """Discrete autoencoder model for compressing pong frames."""
  hparams = autoencoder_ordered_discrete()
  hparams.num_hidden_layers = 3
  hparams.bottleneck_bits = 24
  hparams.batch_size = 2
  hparams.gan_loss_factor = 0.01
  hparams.bottleneck_l2_factor = 0.001
  hparams.add_hparam("video_modality_loss_cutoff", 0.02)
  return hparams