First of all, you need to install the dependencies by using the command:

pip install -r requirements.txt

To run the script, paste this line into Terminal when you are inside the MODNetdirectory:

py -m demo.image_matting.colab.inference --input-path "input/<your_image_file>" --output-path "result" --ckpt-path "pretrained/modnet_photographic_portrait_matting.ckpt"

For example, to delete background for alonso.jpg, put it into the input folder, then use this command to run:

py -m demo.image_matting.colab.inference --input-path "input/alonso.jpg" --output-path "result" --ckpt-path "pretrained/modnet_photographic_portrait_matting.ckpt"

A new file will appear in the result folder, it's a new image without the background named alonso_foreground.png

You can do this with multiple images, just put how many images you want into the input the folder and run the command but the --input-path now is input/ only:

py -m demo.image_matting.colab.inference --input-path "input/" --output-path "result" --ckpt-path "pretrained/modnet_photographic_portrait_matting.ckpt"