Data Science
Sciences and Exploration Directorate - NASA's Goddard Space Flight Center

Innovation Lab Use Case

Optimize Choice in Neural Network

Several state-of-the-art convolutional neural networks were modified for the segmentation of very high-resolution satellite imagery. The applicability of these networks and the effects of underlying hyperparameters was evaluated in the classification of features in 0.5-meter resolution data. The findings were that:

  • Some of the most common networks (shown below) are not designed to identify small and sparse objects.
  • Training and inference time increases drastically as the network integrates more blocks.
  • For Residual Neural Network (ResNet), the bigger the network, the more accurate it becomes.
  • Atrous convolutions, as they are, were found to be inefficient at detecting individual pixels that were outside of a small class group.

truth and prediction thumbnails
Suitability Performance
Small objects accuracy Memory Requirements
Sparse objects accuracy Training Time
Boundary pixels accuracy Classification Time
Overall accuracy Convergence Speed