(1) update README.md. (2) provide some low-quality images for users to inference

install_env.sh

-pip install pytorch_lightning==1.4.2
-pip install einops
-conda install transformers
-conda install chardet
-pip install open-clip-torch
-pip install omegaconf
-pip install torchmetrics==0.6.0
-pip install triton
-pip install opencv-python-headless
-conda install scipy
-conda install matplotlib
-pip install lpips
-pip install gradio