About AMASS SMPL format

[uyoung-jeong]

First of all, thanks for your great and inspiring work, and also releasing and maintaining the code.
I have few questions about SMPL format you used in AMASS for pretraining.

1. I don't have much experience about handling AMASS dataset, so it might be a dumb question.
   From the provided document and the code, I am not sure which SMPL model you used for preprocessing.
   It seems that MotionBERT uses SMPL+H gendered model (link).
   Is it correct that your method also uses SMPL+H gendered model?

2. Regardless of the model format, not all the AMASS data provide all the data for the respective model.
   For example, CNRS and WEIZMANN do not provide SMPL+H data.
   Then, do you simply ignore those data for pretraining?

3. If you use gendered model for pretraining, then does it mean that you do not train with gender-neutral model?
   It seems that female, male, and neutral models have slightly different pose and shape values for the same mesh in AMASS (at least in SMPL-X case).
   Also, previous works such as 3DCrowdNet and ROMP use gender neutral model for training, since we cannot correctly identify gender on in-the-wild data such as COCO.
   Is there something I have missed, or do you just pretrain with gendered model while tolerating some degree of error induced by gender?

[Torian2002]

I'm a newbie in MoCap and want to ask an even dumber question. Should I manually download all 24 of the AMASS datasets used for this project? And what does the optional "render" after AMASS mean?

[uyoung-jeong]

I did some experiments for this, and turns out that SMPL+H genered data can be preprocessed with the provided code.