help with testing

[haoxiaopeng]

I want to testing some lr image, using pre-trained model, seting --ref_dir is None. The line in program is to down_sample input image to 1/4 size of input image, and using input image as ref_image. when I saw the HR image and input image, they are very similar.
My question is: how to not using ref_image when testing, and not downsample input image as ref_image.