Question about Performance without Concatenating Original 2D Features

[haolinyang-hlyang]

I would like to thank you for your excellent work in this paper. I’ve been following your approach with great interest, and I have a question regarding the feature concatenation strategy mentioned in Section 4.6.

You explain that the original 2D features are concatenated with the fine-tuned features to preserve the generalization ability of the original 2D feature extractor while incorporating the 3D awareness of the fine-tuned features.

I’m curious about the impact on performance if, instead of concatenating the original 2D features, one were to use only the fine-tuned features directly (without any assembly strategy). Specifically, I would like to know how this would affect the performance on both within-domain and out-of-domain evaluation.

Any insights would be greatly appreciated!