installation for Ubuntu 20.4

[hongsukchoi]

I am using Ubuntu 20.04 and met some errors while building the environment.

Below are somewhat useful trouble-shooting tips.

Python / Pytorch

Python3.6.9
conda install pytorch torchvision torchaudio cudatoolkit=11.3 -c pytorch

New requirement

h5py
numpy
pyyaml==5.4.1
enum34
future
scipy==1.4.1
opencv_contrib_python==3.4.2.16
matplotlib==3.0.2
transforms3d==0.3.1
scikit_image==0.13.1
lmdb==0.94
setuptools==41.0.0
cffi==1.11.5
easydict==1.7
plyfile==0.6
pillow==8.2.0
glumpy
tqdm
tensorboardX
pandas
scikit-learn
scipy

NormalSpeed

find opencv / 3->4

pybind-11
#17 (comment)

int -> cv::AccessFlag
iterait/hipipe#22 (comment)

This env works well for all training/testing. But training with mixed precision dose not work.