Can none of the models in here be used for denoising real images?

[zhangjy328]

Hello, experts. I have tried multiple models to denoise my images, but there is no effect at all before and after denoising. For example, when testing the DNCNN model, I need to add noise first. I don't understand why I have to add a lot of noise first. Aren't these denoising models? I tried to remove the step of adding noise, but I still can't remove the inherent noise in the image. Can anyone tell me how to denoise real images?