WeijingShi / Point-GNN

Point-GNN: Graph Neural Network for 3D Object Detection in a Point Cloud, CVPR 2020.
MIT License
523 stars 114 forks source link

Questions about Vertex state initialization #98

Open FelipeArenasUribe opened 1 year ago

FelipeArenasUribe commented 1 year ago

Dear authors,

It is clear from your paper that the input to the first MLP for feature extraction is a 1D vector containing the features from the vertex's neighbors. However, I do not understand how you build a 1D vector from a set of 1 or more neighbors?

In your code, the PointSet Pooling class uses as an input a [N, M] tensor with the point features. This wouldn't be consistent with the paper. Can you please explain how this tensor 2D tensor is transformed into a 1D tensor that you use as an input for the feature extraction MLP?

Additionally, Do you use the same MLP for all sets of neighbors? Or do you use a different MLP for each set?