Pyramid Vision Transformer Version 2 + ResNet18

[khawar-islam]

Dear @rwightman

Thank you for your hard work. Would it be possible for you to used ResNet18 for initial feature extraction and then pass to Pyramid Vision Transformer Version 2. PVT is one of the strongest ViT for achieving accuracy. I have tried a lot but it creates a lot of problems because, in PVT, we have four stages.

https://github.com/whai362/PVT/blob/v2/classification/pvt_v2.py